Sorry but to me that looks to be extremely poor leadwork. Too many people don't even know about Soakers or the need for substantial overlaps to keep wind driven rain pushing water up over Soakers if they are fitted, and around Corners, the only way imho to ensure that it is a good job, is to take it apart and start again from scratch. If ot is done properly, Roofers Tippex (Low Mod Neutral Cure Silicone) or Mastic are not needed. tbh, we need to start up proper Apprenticeships again, withbsome decent Roofing Courses at Colleges again. Our Apprentice was on the last Roofing and Slating College Course in Wales, believe it or not, and did an Exhibition Roof Competition at the NEC. He was the inly one who finished off the last course of Slates at the Ridge Properly and securely. The Construction industry is in a bloody bad state all around sadly, and not just in Britain and Europe, it's a Global Problem. Best Wishes. Bob. 😔
I was on the last city guilds roofing course in sussex in 1990 and that was the year it closed. we have the blind leading the blind in roofing now and its unbelievably bad workmanship.
@@Th3_Gael Not Really a waste of time, You get to know the right way to fabricate and install roofs & practice cement work. How kids apply that knowledge in a career is up to the individual roofer. For me that was invaluable and set me ahead of my competitors as I became self employed. I was taught by college a 60 year old roofer who knew almost everything about pitched roofs, also being taught to lead weld was an invaluable skill that combined to make me a lot of money in 30 years in the trade.
@@Th3_Gael The Courses at Universities and Colleges are absolute Crap Today, I went back to get Qualifications for Computer Work I was already doing, and nobody on the IT Course I was in, other then two others like myself already working in the IT Field, got a Job in IT with the Qualification they were given, the Course was so bad. Same Cheap Off the Shelf Course is used right across the EU, and Students in Hamburg University (I was a Software Tester with some of them, and we compared Courses, and found they were the same) were so disgusted they went on strike over it. The RealmPurpose of those Courses was the use of Course Projects to Farm good Marketable ideas from the Students which Companies were making large donations to Universities and Colleges to have access to. No Creditnor Payments made to Students for the Theft of their intellectual property, of course. Just a huge Debt millstone left round their Necks for the "Privilege" of attending just to be Criminally Exploited. I ended up Walking out, and just buying the Microsoft Networking Manuals and the Software I needed, that came with them (not cheap, but they gave me what the Course I had signed for had totally failed to deliver. Frankly, everyone should be Homeschooling their Children, and using pre WW1 Syllabus Content Textbooks. Education went off the Rails after WW1, and the Catastrophic Crash happenedvafter WW2, which accelerated into Loony Tunes from the 1960's. 😡
You mentioned a drone for getting photos. I used some plastic pipe I had laying around taped together with a camera strapped on the end. The flexiness meant it kind of hung over the ridge and pointed directly down at the gutter. A bit of trial and error but worked well.
Hi Roger, Looks to me like the soakers are Not over lapping so instead of discharging the water downwards its going straight down into roof space. That indicates whoever did it doesn't understand the principle of flashings and there could be other mistakes with it out of immediate view. Met a few roofers who didn't understand about soakers.
I had a similar issue on my chimney, different story, concrete block. The render had been frost damaged over the years a d water was getting in, wicking down and coming out in a huge wet patch in the wall, the concrete cap had gone porus as well I think, I re plastered it and built up what was missing from the cap, no problems since, I think part of the problem was the fireplace for that chimney had been blocked off for years and wasn't vented. I was redoing the floor in that room so I just broke into the old fireplace from under the floor, blocked it off in the room, and now we've good ventilation up through the chimney from under the floor, I think that has a good part in keeping it dry too.
Hi Roger. Agreed about the pointing. Regarding the waterproofing (stormdry or other), on chimneys, its must important that the haunching and pot are absolutely weatherproof to prevent excessive moisture soaking down the brickwork and overwhelming the breathing capabilities of the paint on barrier as this can exacerbate the internal damp problem.
100% the pointing is actually catching the rain, every joint has a mil to a cpl of mil catching rain, which will run down to the lowest warmest point….. inside the attic. Another thing I keep on seeing is bad flashing, first lay flashing goes under the roof slates or tiles, then second course flashing on top, which keeps the chimney bone dry at its base. Storm seal…. Class, 5L will honestly give a chimney great protection! Well worth it. But, if your not burning fires or have gas fires, then get rid of chimney! It’s just another thing to look after. All the best
There's an option I used on two chimneys at my terraced house: render then with a drip strip at the bottom and finish with masonry paint to match the colour of the house walls. I also replaced the haunching around the chimney pot with a harder mortar with a steeper slope to shed rainwater and fitted a metal rain cap with mesh below. I love my woodburner but others can use the chimney to vent a gas boiler (or mount a TV aerial). Chimneys have many uses!
It's definitely coursed stone, looks like West Yorkshire (where I am) or possibly East Lancs. That strap pointing was done all over in the 60s to 80s. The structural mortar is of course lime mortar.
Roger, before even watching all your video, I was 99% certain it was driving rain getting through, I know because I’m a builder and have seen this a few times and even on my own bungalow. I live at a 1000ft in rural Wales, we moved 3 years ago and was getting water on our lounge ceiling, stack was soaking in the loft, I redone the lead, repointed, re flaunched it, still getting water, gave it two coats of Thompson’s water seal (not as good as storm dry I know) and it’s been fine since, I do it every summer now. Since then I’ve done it on other properties with the same results, you cannot underestimate how much driving rain will penetrate brickwork, they even call for minimum 120mm cavities here because of it.
@@SBIGDTSM thanks. Will be asking to roofer to do this on my chimney. It's 1.5m high and lots of water penetrating through. Perhaps 3 coats of stormdry will do the trick.
The stone/brick looks very porous, so pointing with a sand/cement mortar is probably not a good idea. Looking at the stain on the ceiling, I would think the problem is probably to do with the rear gutter. A couple of images of the back gutter may have made things clearer. I had a job where the gutter was holding water as it was blocked with organic matter, and when the wind blew the water went over the lead flashing and into the building.
I had exactly the same problem with our chimney, so much so I needed to catch dripping water inside the loft with buckets. I found a crack on the concrete plinth on the very top of the chimney so made a metal cover for that. Coated the whole chimney with Thomson’s water seal…..never leaked since. Interesting video, thank you for sharing.
@@rikardsaje Yes...mine is pretty much flat like a large slab with the chimney pot sat in the middle. I cut out a large piece of galvanised metal sheet that folded over all four edges and with a hole cut for the chimney pot....just sealed around the base of the pot. Between that and the Thompsons water seal on the main stack.....no more leaks.
A few years ago, I had a similar problem with a damp chimney in the attic of our c1912 home. The builder I got in to examine it could find no problem with the structure, render, flashings, etc. The only thing he could suggest was a chimney pot cap to stop rain dropping down the chimney but he couldn't find a cap that would securely fit the oddly shaped pot. I made a cap from 6mm stainless steel plate, which I secured with homemade hooked clamps down the chimney. I also incorporated a 25mm galvanised wire grille at the top, under the SS plate to stop birds nesting in the chimney. The result was a completely dry chimney (& one impressed builder). 😊
Hi Roger, I clicked on this one because I had too many good years trying to solve this sort of problem I did fail a few times and did manage to get to the bottom of most of them, the first thing I notice is that all that new plaster inside was holding all the water used in the mix, about three times as much water as dust!, all that water was just sitting there and as always takes along time to evaporate and even then if it cannot escape will condense on any cold surface. The next thing I was looking for was where was the damp inside?, if it is on the underside of the ceiling and how much is on the wall, the damp that I have seen on walls has never come through the roof, I am not saying that this cannot happen, just that I have never seen it. There was one chimney where I opened up the roof and found no visible issues yet there was some damp on the ceiling. Here you have roughly equal amounts of damp on the ceiling and the top of the wall!. You do not say if the new ceiling was fitted with a vapour barrier and insulation but even if it was it would have been very difficult to seal it at the chimney. The result of all that isn that I would have to open up all the roof from the front all the way up the side and across the back gutter seeking any water tracks, even then absence of evidence is not evidence of absence so re-instatement would involve a new back gutter properly fitted soakers and step flashing and front apron. There would be no guarantee that this would solve the problem!, the two other issues remain unresolved. the second of which is that the chimney itself if unused and capped can trap wet air which will be absorbed by the old soot, that has property known as hydrophilia!, it will soak up moisture if any is available, this moisture will then cool the brickwork when it evaporates the heat then comes through from the inside, the temperature inside can then drop to below the dewpoint of the air in the attic!. There were many occasions in the past when the eyes of the builder that I was trying to explain all this to simply glazed over!, in fact even now I do not actually know for certain that this ever actually happens, just that it is consistent with the laws of physics and chemistry!. I write this and post it to you in the fond hope that you do have the wit to understand it!. Cheers, Richard.
I currently have a problem like this and after inspecting the chimney with a drone (finding that it SEEMs to be OK) suspected that the damp is at a cold point and moisture is condensing there. I stuck a dehumidifier in the room and things have improved. However it hasn't rained much since I did this so it is 50/50 for now. Proof will come in the summer with some heavy rain. If I get damp then I'll start thinking it is the chimney leaking after all!
@@dworkin7110 Hi Dworkin, thank you for your interesting reply, as I tried to explain in my post there is not a great deal you can learn from external observation, really only which bits to open up and investigate. The strategy you outline does make sense, always the more time you can allow for observation the more information you will get and the more information you have the more likely you are to avoid silly errors. There is one thing that might still confound you, that it might well dry out when it stops raining because there is less water lying around cooling things down and the relative humidity is lower too, so when it does rain it is possible for the new wetness to create a cold spot where the damp will appear, the trick then would be to either ventilate the space very effectively or apply the de-humidifier before the rain starts and continue throughout, then if the air inside as really warm and dry but it still shows damp that would indicate a real leak. Much of this confusion about cause and effect is down to the fact that all air carried huge amounts of water as vapour, it is of course dry to the touch band invisible so we tend to ignore it!. Writing this has suddenly made me realise that I should try to find out just how much water a cubic metre of air can hols and how that varies with temperature. I will have to go over to Google and see what I can find, there of course what I find depends on how I ask what questions!. So been therE done that and as far as I could fathom it looks as if a the air in a room of about thirty cubic metres could hold as much as a pint of water!. This is a bit less than I expected but actually if you pout a pint of water on the floor there will be quite a big puddle!. Cheers, Richard.
The biggest issue in general is most chimneys don’t get used anymore. I had a job had looked couple times tried multiple things could not get it resolved then 1 time I went back up the the tiniest little pin prick on a welded corner sealed that sure enough resolved it water gets in anywhere
Another great video Roger, you could (and should) make a full series on common chimney problems. I’ve lived in properties where chimneys have been taken out badly creating structural issues, others that have leaked and been damped like this one. And I’ve found that some roofers don’t want to get involved and some builders just pass it off to roofers.
Great video Roger, I'm with you all the way on the ribbon pointing. Not only can it lead to water ingress, it leaves the masonry vulnerable to frost damage. Another issue to bear in mind with chimneys is that leaks can wash hygroscopic salts (from soot) into the plaster. The salts then absorb moisture from the air keeping the plaster permanently damp even if the original leak is fixed.
I did up a house built in 1850’s and had this exact problem. Had a roofer up two times but was still leaking. After some thinking I came to the conclusion that the whole chimney was like a giant sponge. So spent £1500 to get the chimney replaced. Problem solved.
In old stone houses from the 1880's and 1900s in North Wales the stone chimney stacks are like so many "sponge fingers" soaking up the heavy rain. Loads of work for roofers ! Generally they have to be rendered in two coats of sand cement and waterproofer in the mix. Sorted.
That is what I was thinking, look, the stone is eroding past the mortar. Sure sign, they used the wrong type of stone. From the pictures, the flashing and other parts are very questionable. Never saw a show like this, reminds me of getting kicked off a HVAC forum decades ago for knowing the right fix, they wanted to keep their secrets alike IT people.
Roger - literally watching as I’ve a 1930s property bit of a leak down the inside of ours and thought “Stormdry” brilliant stuff would recommend to anyone but didn’t think it would be suffice on a Chimney! Your a legend fella 👍
Use some stormdry or other brand on the chimney stack walls. Make sure the top of the stack is waterproofed with some slate on a slope or some domed profile. Then fit a Rain Cowl with Mesh or Aspirotor spinning Cowl. The spinning cowl is better because it helps the natural updraft of the chimney drying from inside to out. Point to note. Check the chimney for an opening or air vent down stairs.
Is there a lead tray within the chimney? Stepped lead flashings are designed to protect the junction of the brickwork to the adjoining tiles. They do not stop wet bricks allowing water to pass down into the roof void, this is the job of the tray.
This is completely correct, take down chimney and fit new tray, you can seal bricks and replace all flashing, but it will still leak in the long run. If chimney is not being used as open fire, it will never dry out correctly during winter months, brick become porous, so time for lead tray.
Hi, in the long run, you are very unlikely going to keep it dry, repointing, changing lead, and storm dry will only give it limited life. They look like a London brick, bedded on lime, very porous brick if chimney is not being dried out regular by heat source,like open fire. also, the sand and cement pointing makes it worse. You can always tell if it's time for a rebuild by inside stain on the breast. They show water is being drawn down through the whole stack, not through flashings. In the long run, it will be cheaper to take down and rebuild. Good luck
The thing with chimneys is that they are meant to be used. They are designed to have a good fire blazing away, and the hot fumes would dry out the brickwork. If this is not the case, then the chimney should be capped preferably with a lead sheet on a timber former. I agree with sealing the brickwork also. Both methods used together, will prevent water ingress past the lead flashing, as you covered with the dpc comment. The front lead apron would benefit from a bigger upstand, in line with the stepped flashing to the sides. Also, to me it looks like the plaster has been applied to the chimney directly, whereas it would have been better if it were battened out and plasterboarded.
I had a similar issue with the chimney being wet in the loft. The roof was 90 years old, so we replaced it and also had the chimney re-pointed. The issue continued, I applied stormdry to it and also fitted some chimney caps/cowls/tops. This was done in the spring and 2 years later I've not had the problem again and the chimney inside the loft has stayed dry.
Iv had a roof issue at one of my BTLs for 7 years. Countless roofers couldn’t fix it. In the end I removed the chimney. Think theres still water getting into walls a bit but not as bad. Some projects make no sence.
I have only just remembered that I came across a similar problem to this many years ago in a loft room. It turned out to be condensation running down the felt (due to lack of roof void ventilation) and accumulating at the back of the chimney. Condensation could also take place near the top of the chimney breast itself as this will be relatively cold in the winter. Therefore, if the problem is absent in August its probably at least part condensation. If the chimney is used you would also get condensation on the inside as the warm rising air meets the cold building fabric close to the exterior. The other consideration is hygroscopic damps - the products of combustion produce many contaminants, some of which are hygroscopic and these salts may leach into the brickwork where they will absorb damp from the room - which may be humid. I noticed when last in France that they sometimes clad external chimneys with zinc to provide a rain screen as it is virtually impossible to otherwise prevent damp to a chimney breast which is only inches below a saturated stack.
Great advice, I’ve got a chimney with exact the same problem. I’ve checked the flashing and all possible issues for Water to get in. I’ve even added an extra event in the chimney to create more airflow. Mel has worked. The chimney is at the corner of the house so therefore there is no possibility for water to evaporate before going into the house inside the roof void. It looks like I’ll need to use storm dry to stop water getting into the brickwork in the first place. I have damp problem with two out of three chimneys all in sum on positions. The puzzler but I’m feeling that storm dry is the only option available, which I’ll do this summer. Thanks for the insight. Aidan
Interesting, i dealt with a stack with saturated bricks, even in the middle of summer with flashing that was fine etc. stack had been used to burn coal only all its life, my conclusion was that soot attracted moisture and kept the bricks wet all that time. In the end the stack was removed and the lower brick was coved with a independent stud wall with plaster board.
This house is made from Yorkshire sandstone delph walling, the house next door has been sandblasted. The pointing is way to strong for the stonework, eventually this strength of mortar will destroy the stonework with freeze/thaw, you can’t see all of the chimney, he needs to get up to the roof to have a proper look.
I'm a builder and looking at the stain the back gutter looks like the problem. If the apron flashing upstand is anything to go by I hope your back gutter has a better upstand.
Just thinking about that pointing, might not apply here but I know with Victorian London properties a lot were flushpointed, so the water just runs down the face. That pointing there looks proud, will it pool water and the porous sandstone will absorb it? Try flushpointing in NHL 5?
It could be in Lancs and the house next door is painted. All the houses in Yorks and Lancs are pointed with OPC, but to be fair, most of the time it doesn't damage the house at all, it's very rare it does.
I got fooled by a damp chimney breast. I went up & repaired the chimney rendering, checked all the flashings, ventilation cap etc. And what it turned out to be was hydroscopic salts from 90 years of fires had saturated the fabric of the chimney. So in damp weather, it attracted moisture just as leaving a bowl of table salt out does. I largely resolved it simply by painting the chimney breast with Stainblock & ensuring good ventilation through the unused chimney to keep it as dry as possible.
Normally I would be critical of siloxane treatments as I am not convinced they are a good idea, however I have used them in a very localised manner and found they can work where all else fails. My advice is don't go to the siloxane as a first port of call as repointing in lime should work, but as you say it might need a bit more help? A point worth making is that traditionally chimneys were always in use and this kept them dry, but today they are rarely used and just get wetter.
good video roger !! looks like its leaking at the back of chimney as the water marks on the ceiling is a telltail sign and can definately leak by the silicon holes by the flashings !
by the stains on the plaster first place i would look is the back tray same as you mark and just check the soakers and pointing cant under stand how 4 roofers and so many comments cant see this as water runs down wards think by looks of the pointing just bad roofers
chimney being damp normally would show on the plaster on chimney breast in bedroom below ... looks like its coming either through a cracked or missing slate above chimney or more likely poor / damaged flashings around chimney. Far too strong a mix used on the stone work ..would of been better to use a lime mortar. There's premixed lime mortars available with lots of colours available now that helps make it a fairly simple process. Just read what Richard Harvey wrote and agree 100%. well done Richard for a well written explanation 👏
Really useful video. I have been working my way through the same issue and had decided to use Stormdry next summer. Stupidly I have closed off the chimney to stop the draught in my lounge. So will also open up the chimney (hadn't thought of that before seeing this video).
As you have already hinted at it would appear the damp is trapped within the internal finishes - easy to say but it is advisable to open up internally , inspect and allow to dry out.
At 2:18 to 2:40, I can see that the chimney is leaning to the left; while pretty much square to the roof it isn't vertical. I don't know if that's a cause of the dampness, an effect, or just a red herring, but it doesn't seem right.
I had a similar issue ... builder up and made a mess of my flashing which was as far as he could stretch basically, to no avail....popped an old camera on a fishing rod and filmed the very top from a safe ladder height, around the pots and found the crack across the cement cap...bought a scaffold tower and fixed it myself...solved. just need to start from the top, not just where you can get to...
I've also noticed the gaps in the fibre cement slates, depends on where he lives & which way his house is pointing he could have water being pushed up under those slates. basically like a capillary action. If he finds that most of the time the wind blows over this side of the roof then there's your problem.
Lots of logical comments been made already, but the colour of the staining indicates mineral contamination which is probably very hygroscopic and possibly will never dry. I’m a damp surveyor and I see this hygroscopic damp problem a lot below old chimneys. I’ve seen perfectly good chimneys removed completely and tiled over, but the damp patch below still never dries. I think it could be part of the issue here.
1min 30 seconds in ….,thermal image the chimney breast & take photos Then garden hose out of the loft window & saturate the c/Breast ….thermal again Depending on outside temperature & fabric temp ….you should see something V difficult (but we have done it) connect G/hose to hot water from combi & spray area with hot water You then have the cooler brick work + hot water / now you have a larger temp differential….easy to find weak spot or spots
I’d say there’s an issue in the leadwork behind the chimney, water is pooling on the plasterboard at the back of the chimney and then running down the side of the chimney, the watermarks tell the story. If the chimney was allowing water to permeate through there would be a more even spread of a visible damp patch and watermarks whereas in this occasion it is concentrated at the back of the chimney and then finding it’s way down the ceiling alongside the chimney.
The rear of my house faces the weather - wind driven rain - and I gave it a coat of storm dry and I swear it even made the rear rooms warmer as well as waterproofing the wall, all for a couple of tubs of it!
In the future you need to give out the area of where these houses are because not only might there be someone there who could fix it, but also local knowledge (of weather and materials) is very useful. It would also be good to know where the most winds are coming from in relation to the leaks. It looks to me like a North Eastern Lancashire house, possibly Colne or Burnley, somewhere round there. WDR and porous stone is a big problem in that area and the fact the house next door has been painted says something. I would agree with Stormdry, but need to warn you of something. If it's done with that and then needs repointing, the pointing won't stick! That is if it's managed to soak into the joints, maybe all that horrible strap pointing will stop it. The other thing to note is that some of the houses out that way (Pennines) get so much WDR that it even gets through Siloxane, wets the wall and still runs in.
I have a house near Accrington which was painted when I bought it almost 20 years ago, and quite damp Had the front wall (of stone) sandblasted a few years ago and the wall has dried out and remained dry since. Painting or rendering don't always do buildings any favours
Easiest thing would be to take down the damp plaster area and expose the chimney from the inside. Dry the timber and wait for the next rain fall, find the exact spot where the water is coming in.
@@alexp1054well there is gravity, which means everything flows downwards. Far easier to remove interior plasterboard , than put someone on the roof. You might even get lucky. On a sunny day, there might be a chnk of light . Especially if you put a blanket on the window and close the door into darkness.
@@Jeremy64444 you forget capillary action of water. Just because water appears in one location visible to the observer, it might be entering at a totally different location, sometimes lower than seen. But your idea is a good one because it will allow the moisture to dry once the area is uncovered.
@@0skar9193 capillary action will leave a trail. Entering at one point, finishing at another. You still will have a track. Use a sunny day to check for sunlight. Use a day of high rainfall to check for the leak.
I agree with you, the chimney has had various efforts but attention to detail is the key, the pointing is hard sand/cement (I would use lime mortar) and lead mate in the flashings is good as it dosnt crack with the movement of the lead during temperature change but I would like to see it fill all the joint (look a bit inconsistant/ gappy) as theres no damp course in this I would plumb for sealing it with storm guard or similar and make sure the flaunching is sound on the top with no cracks and fit a vented cap if not in use. You have to remember these bricks have seen it all in terms of "weather battering" and are likley to be very weathered. Chimney is only single skin with a draught going through it (if its an open fire place) so vent it and seal it I aggree. You shouldnt have any more issues. 👍
Check,back gutter for leaks,rake out and repoint chimney with weather struck joints,make sure top and corbel course are correctly flaunched,cap and vent any unused flues and maybe hack off internal gypsum plaster and use lime instead? Hope that helps?
Sorry Roger - not bricks... Yorkshire stone. I had the same problem with my back gutter. Replaced it, but still got water seeping in when the wind drives the rain against it. My chimney is brick. Eventually I gave the whole chimney a coat of that silicone cream. That solved it.
@@SkillBuilder No problem, I wasn't having a go - just giving the info. This type of stone often delaminates to a degree. If you look carefully at it, it is made up of thin layers of sediment (as Edward has pointed out.) What can happen over the decades is that water gets in between the layers, expands as it freezes, opening up the gap between the layers of sediment very slightly. Once that has occured, water will subsequently be drawn in by capilliary action; it doesn't 'soak' through - it's actually pumping it through. I've seen a case where patio doors had been put in a wall in an old Yorkshire cottage, without a tray. Water poured in above the door, when rain drove against it. Our boss told us to give the wall a coat of DPC silicon (long before this paste came out.) We scoffed at the suggestion, but the boss is the boss 😉. It cured it permanently. completely, so
It isn't just to strong a mix it isn't weather struck, the top of the pointing protrudes past the line of the masonry and it should "tuck" under it. Aside from that the flashings aren't great and if the chimney isn't used some damp could be internal.
I wonder if the chimneys blocked off with no air vent You can get condensation building up inside the chimney stack what do you think? Open it up and get some airflow
Hi Roger . One of the potential problems for owners of older properties like me where sand lime mortar jointing dried out excessively due to last years drought . Unfortunately this led to wicking effect . So with the joints getting soaked by rainwater the internal walls can not dry out fast enough during the winter months . We therefore have to wait for the summer months to dry out the rooms .
My chimney was leaking when it rained due to the bricks being very porous so I tried a version of siloxane yogurt stuff which worked a treat. The bricks in the loft were soaked previously but are bone dry now.
Worked on these for years. Its the soakers they aren't overlapping they aren't long enough. The flashing isn't overlapping enough too. Agree with the storm dry on these old stone houses they have been up 120 years sometimes every little helps. Should see lead poking out of every slate at the side of the chimney
I could really do with your expertise, I have a problem with my chimney, I have had several people try to fix it, but every winter, sure enough we get some damp on the ceiling, flaking paint on the ceiling, salts coming out of the plasterboard and wall.... definitely want it sorted out, Croydon based here. The chimney is part of an extension that was built in 1996 and has apparently never been right!
We have had chimney scaffold up for two years. Had the pots capped, pointing repaired, stormdry applied. Still a slight damp issue. All the lead looks good. My neighbour and myself are wondering if the lead valleys have become porous. The house is 80 years old. However, it's an ex council property and the council replaced all the roofs in the 70's and sprayed foam insulation into the cavities. Next step is to check all the copper pipes in the loft. Work has been done and we know that in the 70's cheap impure copper was the only tube available and it was contaminated with particles of iron. The iron rusts and small pinholes appear. It's been a nightmare.
Could be water going down the chimney pots. A few builders misdiagnosed damp spots around my chimney.. Suggested I needed to scaffold the whole house and take them down. A new £30 cowl fixed it.
The culprit is that pointing job! Someone used a strong mix of cement mortar and cement will retain water for a very long time. Also as @MrDimensionalStone said the pointing is way to strong for the stonework, so it will crack over time and water seeps in. He probably has the same problem in outer walls but insulation prevents from going to inner walls. He should also check the top (flat part) of the chimney. I live in Portugal and for many years people used to restore old houses with granite walls repointing with cement mortar. This led to problems with water ingress and cracking. These days we use lime mortars compatible with the stone.
Warm flue and a cold flue can cause condensation. Have seen that run like a tap before. Not saying its the case here but that one will get you scratching your head. Took a chimney down twice on that one
Think there's a multitude of problems here. Pointing for one, never had any faith in cement strap pointing. All it does is cause damp and over time, damages brick as we can see in some of the photos. If you visit houses with that kind of pointing, I would wager that all have damp. The stepped lead flashing needs tidying up properly. Do we even know if that flashing is rolled inside the mortar joint or is it just pushed in flat. The apron as you say could have done with being up at least another course. Mortar on lead does not seal effectively as water will travel through the mortar and where the mortar meets the lead. I see something that resembles a join between properties, I would be having a look at that aswell.
I have exactly the same problem! Six different roofers have not been able to fix it. I have a pet paddling pool in the loft catching the water. Am at my wits end after having so much done by different contractors and paid so much. Fed up. How can so many professionals not know what the problem is!
As an architect the pattern of damp emanates from the rear of the stack. Ring wind can hold a 100 mm head of water and a lot of water is hitting the back of the stack and running down onto the back flashing. I would replace the back soakers and flashings ensuring the lead has as deep a bed as possible. Then treat the tack with a sprayed waterproofed or render the back face. With waterproof render.
Hi Roger, if this person doesn't use one of these flues they need to make sure it is vented top and bottom or this will cause big problems as the air oassung by helps ti wick the moisture away 😊👍🏻
🧐🧐great video mate i had similar job two years ago ..after replacing all lead work and felt batten etc correctly it was still coming back on bad heavy rain showers. on second attempt i did all repointing and could see The problem ..on removing the old cement it was getting behind and most bricks were saturated finally had solved the problem
I live in a cottage built in 1820, water running down chimney in loft. The bricks were soaking water like a sponge. Stormdry solved the problem. Fantastic stuff. Goes on white and creamy but soaks in and then after a day or two you'd never know it was on.
Just plain Laminating epoxy Resin works well, To arrive coat fibreglass boat hulls and Cast iron Keels 3 coats does the job at a fraction of the price of Barrier Coat from Chandlers. Silicon DPC Would work on Bricks and be even cheaper. would work on porous stonework as well. Just paint it on until it stops absorbing any more. It's used for putting a Damp proof course into Stone Walls by pumping it in up to ground level, 5 gallon Drums of it used to be a reasonable price. The problem with Bricks , clay tiles Ridge tiles and Finials is they aren't fired at a high enough temperature, so the service life of Facing Bricks for example, is they have a service life if only about 400 years before going porous, and a lot less if the manufacturer drops the Firing temperature to save a lot of money. There are manufacturers who do fire at the correct Temperature but for things like ridge tiles, they Warp, so users need to be aware that a bit more effort is needed to fit them so they look nice, worth it for the much better product though. If a customer bought a roof off me, in Natural Slate (which I specialised in ) I usually earned a nice profit on the Foreign Exchange Currency Purchase, to give them a nice discount on the overall Roof Package , and with assistance on getting things right, it was amazing what a good job DIY refurbished could turn out, and for a lot less money than getting a Cowboy Roofer to do it, all it took was instructions when they needed help, plus Brain engaged and Patience. That was probably the most job Satisfaction I've ever had, and years later, going past their Beautiful Roof, is a heck of a buzz still. Best Wishes. Bob. 👍
Got a leaky chimney possibly and it’s been given plenty of coatings of modern stuff. Hoping I can get a builder to use lime for rebuilding the chimney.
Sounds like very sensible advice to me as all external finishes should allow evaporative drying as you rightly point out. Also he should indeed follow your advice an have the back-gutter checked. If the flues are disused I might also suggest fitting pepper pots to these to prevent rain going down the pots. Rain-hoods would be an alternative if they are in use. That pointing is wrong practically and visually as you say!
I lived in a house for 25 years ...had the same problem . Had all the local roofers take a look and spent thousands. Had it repointed ....new flashing and water seal . It was still leaking when I moved house !
Quite a few things could be happening there, hard to say from brief pics, but maybe even water flowing along the ridge under the tiles from a neighbouring roof? I think I'd try a process of elimination starting by tying a tarpaulin tight around the chimney to see if the water is really coming from there? Though repeat visits will get expensive for the builder, I suspect, as people like an instant correct answer.
The pointing is the issue more than the type of sand and strength they have used. Pointing should sit just under the brick above it and chamfered to create run off. That pointing is trapping rain water at the top of the pointing due to it coming out further than the brick.
Roger, I notice that there are no chimney cowls so water entering the stack ?. Is the stack servicing a fire that's regularly lit during winter and is the fireplace made up ? Apart from that a few open apertures around pointing and flashing to be filled, then as you said, a good coating of Storm Seal applied in summer when the stack has dried out. Owner could do this himself with not too much expense.
Is the chimney still being used for a fire? In times gone by when it was cold or wet the fire would have been lit and the heat from fire would have warmed up the chimney and driven the damp out through the bricks. If the fire is no longer used the chimney should be capped off with a ventilated pot and vent lower down. When the bricks have dried out use Storm Dry as you suggest.
either soakers don't start far enough up or back gutter is inadequate ! can't see the pointing being the issue... though it isn't ideal and would be worth weather pointing if you are accessing the chimney anyway.. a brick treatment is a good idea as suggested but I still feel there is a greater problem on the back flashing!
Loft conversion with almost certainly no lead or damp proof break between exterior or interior chimney brickwork. Pointing and brickwork suffering from osmosis and transmitting damp into loft space that is now a room, not a vented roof space. The cold and damp brickwork is now almost certainly cold bridging and attractive humidity from the house and rooms below, adding to the damp plaster. Just my opinion.
I often find a chimney rebuild with a lead tray. these old stacks were often built without them and were ok while as the damp had a metre or so to dry out in the attic.. the problem cmae when the attic was converted into a room and not allowing the damp from the outside to dry out.
I would say a problem with the back flashing. Or wrong instalation of roof felt with water actually coming from further up the roof then depositing at the end of the felt run
It’s salt damp a salts analysis test will prove it. So it’s hygroscopic salting attracting moisture from the internal air. It’s very common. A client of mine spent thousands and even had the chimney removed still same problem. All spent unnecessarily it was salt damp. I am a damp and timber surveyor.
Looks to me like Bradford / Halifax / Keighley area. I suspect the soakers and back gutter. As built these had a very narrow & sloping back gutter, so when you replace the slates you can't just bang in new lead, it needs new wood under to support it too. It looks to me like the rear gutter has just been 'bossed' that's to say formed by hammering it, rather than lead burning (welding) it. I suggest get a proper roofer to strip the slates then replace & / or inspect the soakers making sure they are fixed to the batons and are the correct height & width. The step flashing front corner requires replacement as does the pointing, as mentioned. Lastly the back gutter may need removal for full inspection as even pin holes can be enough to cause a problem. The back gutter upstand itself should be covered by a flashing pointed into the stone ( yes, it's stone) at least 4" above the flat part of the back gutter.
You are spot on with all that and yes when I looked at that back gutter again it does look a bit rough. Bossing a back gutter is not wrong but it has to be done properly and not just with your boot. Also the fact that the roofs run downhill means the angle of creep is more.
@@RicktheRecorder Interesting, as a welder & panel beater in a previous career I would say welding lead is a tricky skill to get right... bossing for me would be the way to go but it needs to be done properly
@@0skar9193 Lead burning requires a knack, but once you have it you can make any shape with equal ease. Bossing requires different skills for each shape.
The chimney on the right hand side is also pointed in the same way, Probably a pin hole, or tiny crack in the lead at rear of the stack dripping on to the timber support board beneath. Lead goes thin when beaten to stretch around a right angle ,plus age and degradation. Staining on the ceiling is mainly to rear and tracking down part way.
If the internal fireplaces have been blanked off they must be ventilated or condensation will produce this problem . I would want to know what the chimneys are now used for .
Roger didn't mention much the other reason that pointing is so bad in this situation- it holds the rainwater. It doesn't alow the water to flow off well so it kind of hangs about on the brickwork much longer than it should. The stack needs everything possible tipped in it's favour if it's not going to leak.
Seen same problem..the entire stack looks saturated due to the pointing actually channelling rain in and poor silicon job - it will refuse to dry without some help! Solution was to rake it right back, check soakers etc then put a temp breathable roof felt covering over it and make sure its venting well then let it dry out over summer. Once dry weather struck point with soft lime mix
I agree with comment below, lead work looks substandard, take the lot off and start again, can spend a fortune on people jumping up there with a mastic gun. A good roofer who can weld lead will have it sorted for good! Just my humble opinion as invited to offer.
Lead work doesn’t look great but I have seen issues where a cracked cap caused issues like this and also had issue with some bricks just absorbing the the water and it’s coming threw them below the lead. Few coats of Thomson’s or a worst case render it with sand and cent with added waterproofer. That’s my personal opinion.
Look at pic on page 8:09. There you can see each bit of flashing is basically a narrow sheet of lead that barely extends to the left beyond the margin of the next section of flashing. This allows water to creep along in that overlap, then migrate further inwards to the brick. Those sections of flashing should have their entire face be shaped like a triangle with the top going into the mortar, then the next section coming down over it, not leaving unflashed small sections. There lies the source of the leakage problem - bad, incomplete flashing sections..
Totally agree. Also the general 'quality' of the flashing would make me suspicious the soakers were inadequate as well. I can't help but wonder if the perpetrator of the ribbon pointing was also responsible for the leadwork?
Maybe the water ingress problem has been fixed and what we are now seeing is the stain coming through the emulsion paint. From what I can make out it looks like it could well be that. Easy way for the homeowner to test would be draw around the stain with a pencil. Wait a couple of days after a downpour of rain and check your pencil line. If no change to size then use a stain block paint in that area. After that emulsion the area as normal. Obviously I may be wrong but thats why I say draw around it and check first.
havnt read comments chimneys are built only single skin brickwork if no longer in use never get chance to dry out fully if not in use need to be capped off and air flow introduced most commonly by the addition of air bricks
I've got a soaking chimney a black water goop twickles down the inside of the chimney making a huge mess at the bottom. I've repointed twice, weather shield it, and put loads of roof repair paint from the leading to the damp proof lining and coated the top around pots for good measure but still no improvement. It's a flued lined chimney. Should I put a breath brick in up there? Also, how do you dry it? Lighting the fire does it but the wet returns. Yours desperately!
First try the Thompson's water seal or some thing similar. If that does not work Then Re lead the stack, Bell cast beads around the base of the stack, scratch coat , render and re flaunch the top of the stack with wash sand cement or if the chimney is not in use then drop it below roof line and felt, batten and slate over the void!
I see this regular I would say its 90% that its Cold(Thermal) Bridging causing condensation on the restricted ceiling space with all the moisture in the house rising up to the converted roof-space.
I have a very similar problem. It seems like the brick is soaked and went black with damp. Flashing all looks sound. Had a guy come and look at it and sand blasted the brickwork and repoint. Now its exactly the same state. I figured getting a pro in was the best thing to do as they'd sort it quickly rather than me take time off work I'll be going up to clear it up myself now.
I'd absolutely agree with the Stormdry treatment. Also what about the haunching and pots? Is the haunching cracked and crumbly? Are the pots still used and if not have they been capped against rain ingress (with ventilation of course!)
So refreshing to hear a builder advocating lime mortar these days! Thank you for the video, Roger
Sorry but to me that looks to be extremely poor leadwork. Too many people don't even know about Soakers or the need for substantial overlaps to keep wind driven rain pushing water up over Soakers if they are fitted, and around Corners, the only way imho to ensure that it is a good job, is to take it apart and start again from scratch. If ot is done properly, Roofers Tippex (Low Mod Neutral Cure Silicone) or Mastic are not needed. tbh, we need to start up proper Apprenticeships again, withbsome decent Roofing Courses at Colleges again. Our Apprentice was on the last Roofing and Slating College Course in Wales, believe it or not, and did an Exhibition Roof Competition at the NEC. He was the inly one who finished off the last course of Slates at the Ridge Properly and securely. The Construction industry is in a bloody bad state all around sadly, and not just in Britain and Europe, it's a Global Problem. Best Wishes. Bob. 😔
PS. The Pointing between Courses is rubbish as well tbh. 😒
I was on the last city guilds roofing course in sussex in 1990 and that was the year it closed. we have the blind leading the blind in roofing now and its unbelievably bad workmanship.
Colleges are a waste of time, unless you want them to learn more about not hurting people's fee fees and the religion of rainbows
@@Th3_Gael Not Really a waste of time, You get to know the right way to fabricate and install roofs & practice cement work. How kids apply that knowledge in a career is up to the individual roofer. For me that was invaluable and set me ahead of my competitors as I became self employed. I was taught by college a 60 year old roofer who knew almost everything about pitched roofs, also being taught to lead weld was an invaluable skill that combined to make me a lot of money in 30 years in the trade.
@@Th3_Gael The Courses at Universities and Colleges are absolute Crap Today, I went back to get Qualifications for Computer Work I was already doing, and nobody on the IT Course I was in, other then two others like myself already working in the IT Field, got a Job in IT with the Qualification they were given, the Course was so bad. Same Cheap Off the Shelf Course is used right across the EU, and Students in Hamburg University (I was a Software Tester with some of them, and we compared Courses, and found they were the same) were so disgusted they went on strike over it. The RealmPurpose of those Courses was the use of Course Projects to Farm good Marketable ideas from the Students which Companies were making large donations to Universities and Colleges to have access to. No Creditnor Payments made to Students for the Theft of their intellectual property, of course. Just a huge Debt millstone left round their Necks for the "Privilege" of attending just to be Criminally Exploited. I ended up Walking out, and just buying the Microsoft Networking Manuals and the Software I needed, that came with them (not cheap, but they gave me what the Course I had signed for had totally failed to deliver. Frankly, everyone should be Homeschooling their Children, and using pre WW1 Syllabus Content Textbooks. Education went off the Rails after WW1, and the Catastrophic Crash happenedvafter WW2, which accelerated into Loony Tunes from the 1960's. 😡
You mentioned a drone for getting photos. I used some plastic pipe I had laying around taped together with a camera strapped on the end. The flexiness meant it kind of hung over the ridge and pointed directly down at the gutter. A bit of trial and error but worked well.
Hi Roger,
Looks to me like the soakers are Not over lapping so instead of discharging the water downwards its going straight down into roof space. That indicates whoever did it doesn't understand the principle of flashings and there could be other mistakes with it out of immediate view. Met a few roofers who didn't understand about soakers.
Agreed. Even as a lay woman I could see that.
I had a similar issue on my chimney, different story, concrete block. The render had been frost damaged over the years a d water was getting in, wicking down and coming out in a huge wet patch in the wall, the concrete cap had gone porus as well I think, I re plastered it and built up what was missing from the cap, no problems since, I think part of the problem was the fireplace for that chimney had been blocked off for years and wasn't vented. I was redoing the floor in that room so I just broke into the old fireplace from under the floor, blocked it off in the room, and now we've good ventilation up through the chimney from under the floor, I think that has a good part in keeping it dry too.
Hi Roger. Agreed about the pointing. Regarding the waterproofing (stormdry or other), on chimneys, its must important that the haunching and pot are absolutely weatherproof to prevent excessive moisture soaking down the brickwork and overwhelming the breathing capabilities of the paint on barrier as this can exacerbate the internal damp problem.
Water evaporates in the warmest climes? inside...
100% the pointing is actually catching the rain, every joint has a mil to a cpl of mil catching rain, which will run down to the lowest warmest point….. inside the attic. Another thing I keep on seeing is bad flashing, first lay flashing goes under the roof slates or tiles, then second course flashing on top, which keeps the chimney bone dry at its base. Storm seal…. Class, 5L will honestly give a chimney great protection! Well worth it.
But, if your not burning fires or have gas fires, then get rid of chimney! It’s just another thing to look after.
All the best
There's an option I used on two chimneys at my terraced house: render then with a drip strip at the bottom and finish with masonry paint to match the colour of the house walls. I also replaced the haunching around the chimney pot with a harder mortar with a steeper slope to shed rainwater and fitted a metal rain cap with mesh below. I love my woodburner but others can use the chimney to vent a gas boiler (or mount a TV aerial). Chimneys have many uses!
It's definitely coursed stone, looks like West Yorkshire (where I am) or possibly East Lancs. That strap pointing was done all over in the 60s to 80s. The structural mortar is of course lime mortar.
Roger, before even watching all your video, I was 99% certain it was driving rain getting through, I know because I’m a builder and have seen this a few times and even on my own bungalow.
I live at a 1000ft in rural Wales, we moved 3 years ago and was getting water on our lounge ceiling, stack was soaking in the loft, I redone the lead, repointed, re flaunched it, still getting water, gave it two coats of Thompson’s water seal (not as good as storm dry I know) and it’s been fine since, I do it every summer now.
Since then I’ve done it on other properties with the same results, you cannot underestimate how much driving rain will penetrate brickwork, they even call for minimum 120mm cavities here because of it.
Hi interested to know did you repoint in lime or just cement?
@@KatherineG-u7i just sand and cement.
The biggest improvement was the damp treatment, Thompson’s water seal or storm guard
@@SBIGDTSM thanks. Will be asking to roofer to do this on my chimney. It's 1.5m high and lots of water penetrating through. Perhaps 3 coats of stormdry will do the trick.
The stone/brick looks very porous, so pointing with a sand/cement mortar is probably not a good idea. Looking at the stain on the ceiling, I would think the problem is probably to do with the rear gutter. A couple of images of the back gutter may have made things clearer. I had a job where the gutter was holding water as it was blocked with organic matter, and when the wind blew the water went over the lead flashing and into the building.
If the skirt at the front doesn't go up very high perhaps the one at the back doesn't either?
Stone is porous and year's of acrid smoke damages the stone and makes it more so sadly
I had exactly the same problem with our chimney, so much so I needed to catch dripping water inside the loft with buckets. I found a crack on the concrete plinth on the very top of the chimney so made a metal cover for that. Coated the whole chimney with Thomson’s water seal…..never leaked since. Interesting video, thank you for sharing.
In this case without ventilation at the top and bottom your chimney will sweat and rot from the inside 😞
@@audid00dy the chimney is in use so plenty of ventilation…..but you are right if the chimney had been sealed👍
Hi, I've got a similar problem, do you mean the flaunching on the top where the chimney pots sit?
@@rikardsaje Yes...mine is pretty much flat like a large slab with the chimney pot sat in the middle. I cut out a large piece of galvanised metal sheet that folded over all four edges and with a hole cut for the chimney pot....just sealed around the base of the pot. Between that and the Thompsons water seal on the main stack.....no more leaks.
A few years ago, I had a similar problem with a damp chimney in the attic of our c1912 home. The builder I got in to examine it could find no problem with the structure, render, flashings, etc. The only thing he could suggest was a chimney pot cap to stop rain dropping down the chimney but he couldn't find a cap that would securely fit the oddly shaped pot. I made a cap from 6mm stainless steel plate, which I secured with homemade hooked clamps down the chimney. I also incorporated a 25mm galvanised wire grille at the top, under the SS plate to stop birds nesting in the chimney.
The result was a completely dry chimney (& one impressed builder). 😊
Hi Roger, I clicked on this one because I had too many good years trying to solve this sort of problem I did fail a few times and did manage to get to the bottom of most of them, the first thing I notice is that all that new plaster inside was holding all the water used in the mix, about three times as much water as dust!, all that water was just sitting there and as always takes along time to evaporate and even then if it cannot escape will condense on any cold surface.
The next thing I was looking for was where was the damp inside?, if it is on the underside of the ceiling and how much is on the wall, the damp that I have seen on walls has never come through the roof, I am not saying that this cannot happen, just that I have never seen it. There was one chimney where I opened up the roof and found no visible issues yet there was some damp on the ceiling. Here you have roughly equal amounts of damp on the ceiling and the top of the wall!.
You do not say if the new ceiling was fitted with a vapour barrier and insulation but even if it was it would have been very difficult to seal it at the chimney.
The result of all that isn that I would have to open up all the roof from the front all the way up the side and across the back gutter seeking any water tracks, even then absence of evidence is not evidence of absence so re-instatement would involve a new back gutter properly fitted soakers and step flashing and front apron. There would be no guarantee that this would solve the problem!, the two other issues remain unresolved. the second of which is that the chimney itself if unused and capped can trap wet air which will be absorbed by the old soot, that has property known as hydrophilia!, it will soak up moisture if any is available, this moisture will then cool the brickwork when it evaporates the heat then comes through from the inside, the temperature inside can then drop to below the dewpoint of the air in the attic!. There were many occasions in the past when the eyes of the builder that I was trying to explain all this to simply glazed over!, in fact even now I do not actually know for certain that this ever actually happens, just that it is consistent with the laws of physics and chemistry!.
I write this and post it to you in the fond hope that you do have the wit to understand it!.
Cheers, Richard.
I currently have a problem like this and after inspecting the chimney with a drone (finding that it SEEMs to be OK) suspected that the damp is at a cold point and moisture is condensing there. I stuck a dehumidifier in the room and things have improved. However it hasn't rained much since I did this so it is 50/50 for now. Proof will come in the summer with some heavy rain. If I get damp then I'll start thinking it is the chimney leaking after all!
@@dworkin7110 Hi Dworkin, thank you for your interesting reply, as I tried to explain in my post there is not a great deal you can learn from external observation, really only which bits to open up and investigate. The strategy you outline does make sense, always the more time you can allow for observation the more information you will get and the more information you have the more likely you are to avoid silly errors.
There is one thing that might still confound you, that it might well dry out when it stops raining because there is less water lying around cooling things down and the relative humidity is lower too, so when it does rain it is possible for the new wetness to create a cold spot where the damp will appear, the trick then would be to either ventilate the space very effectively or apply the de-humidifier before the rain starts and continue throughout, then if the air inside as really warm and dry but it still shows damp that would indicate a real leak.
Much of this confusion about cause and effect is down to the fact that all air carried huge amounts of water as vapour, it is of course dry to the touch band invisible so we tend to ignore it!.
Writing this has suddenly made me realise that I should try to find out just how much water a cubic metre of air can hols and how that varies with temperature.
I will have to go over to Google and see what I can find, there of course what I find depends on how I ask what questions!.
So been therE done that and as far as I could fathom it looks as if a the air in a room of about thirty cubic metres could hold as much as a pint of water!. This is a bit less than I expected but actually if you pout a pint of water on the floor there will be quite a big puddle!.
Cheers, Richard.
The biggest issue in general is most chimneys don’t get used anymore.
I had a job had looked couple times tried multiple things could not get it resolved then 1 time I went back up the the tiniest little pin prick on a welded corner sealed that sure enough resolved it water gets in anywhere
Another great video Roger, you could (and should) make a full series on common chimney problems. I’ve lived in properties where chimneys have been taken out badly creating structural issues, others that have leaked and been damped like this one. And I’ve found that some roofers don’t want to get involved and some builders just pass it off to roofers.
Great video Roger,
I'm with you all the way on the ribbon pointing. Not only can it lead to water ingress, it leaves the masonry vulnerable to frost damage. Another issue to bear in mind with chimneys is that leaks can wash hygroscopic salts (from soot) into the plaster. The salts then absorb moisture from the air keeping the plaster permanently damp even if the original leak is fixed.
I did up a house built in 1850’s and had this exact problem. Had a roofer up two times but was still leaking. After some thinking I came to the conclusion that the whole chimney was like a giant sponge. So spent £1500 to get the chimney replaced. Problem solved.
In old stone houses from the 1880's and 1900s in North Wales the stone chimney stacks are like so many "sponge fingers" soaking up the heavy rain. Loads of work for roofers ! Generally they have to be rendered in two coats of sand cement and waterproofer in the mix. Sorted.
Would it problematic to use engineering bricks for a chimney?
@@unibks4382 Would not think so? They are stronger and more water proof, but looks a bit less attractive.
@@unibks4382 fine but overkill
That is what I was thinking, look, the stone is eroding past the mortar. Sure sign, they used the wrong type of stone. From the pictures, the flashing and other parts are very questionable. Never saw a show like this, reminds me of getting kicked off a HVAC forum decades ago for knowing the right fix, they wanted to keep their secrets alike IT people.
Roger - literally watching as I’ve a 1930s property bit of a leak down the inside of ours and thought “Stormdry” brilliant stuff would recommend to anyone but didn’t think it would be suffice on a Chimney! Your a legend fella 👍
Use some stormdry or other brand on the chimney stack walls. Make sure the top of the stack is waterproofed with some slate on a slope or some domed profile. Then fit a Rain Cowl with Mesh or Aspirotor spinning Cowl. The spinning cowl is better because it helps the natural updraft of the chimney drying from inside to out. Point to note. Check the chimney for an opening or air vent down stairs.
Is there a lead tray within the chimney? Stepped lead flashings are designed to protect the junction of the brickwork to the adjoining tiles. They do not stop wet bricks allowing water to pass down into the roof void, this is the job of the tray.
It is very unusual to find a lead tray in an old stack on that kind of housing
This is completely correct, take down chimney and fit new tray, you can seal bricks and replace all flashing, but it will still leak in the long run. If chimney is not being used as open fire, it will never dry out correctly during winter months, brick become porous, so time for lead tray.
@@clivefox5072 If it's not being used no point going to the extra cost of a rebuild
@@peterthebricky only for looks
Hi, in the long run, you are very unlikely going to keep it dry, repointing, changing lead, and storm dry will only give it limited life. They look like a London brick, bedded on lime, very porous brick if chimney is not being dried out regular by heat source,like open fire. also, the sand and cement pointing makes it worse.
You can always tell if it's time for a rebuild by inside stain on the breast. They show water is being drawn down through the whole stack, not through flashings.
In the long run, it will be cheaper to take down and rebuild.
Good luck
The thing with chimneys is that they are meant to be used. They are designed to have a good fire blazing away, and the hot fumes would dry out the brickwork. If this is not the case, then the chimney should be capped preferably with a lead sheet on a timber former. I agree with sealing the brickwork also. Both methods used together, will prevent water ingress past the lead flashing, as you covered with the dpc comment. The front lead apron would benefit from a bigger upstand, in line with the stepped flashing to the sides. Also, to me it looks like the plaster has been applied to the chimney directly, whereas it would have been better if it were battened out and plasterboarded.
I like the chimneys in Brittany, France, they tile them, seems to keep out the similar weather we have in the U.K.
I had a similar issue with the chimney being wet in the loft. The roof was 90 years old, so we replaced it and also had the chimney re-pointed. The issue continued, I applied stormdry to it and also fitted some chimney caps/cowls/tops. This was done in the spring and 2 years later I've not had the problem again and the chimney inside the loft has stayed dry.
Iv had a roof issue at one of my BTLs for 7 years. Countless roofers couldn’t fix it. In the end I removed the chimney. Think theres still water getting into walls a bit but not as bad. Some projects make no sence.
I have only just remembered that I came across a similar problem to this many years ago in a loft room. It turned out to be condensation running down the felt (due to lack of roof void ventilation) and accumulating at the back of the chimney. Condensation could also take place near the top of the chimney breast itself as this will be relatively cold in the winter. Therefore, if the problem is absent in August its probably at least part condensation. If the chimney is used you would also get condensation on the inside as the warm rising air meets the cold building fabric close to the exterior. The other consideration is hygroscopic damps - the products of combustion produce many contaminants, some of which are hygroscopic and these salts may leach into the brickwork where they will absorb damp from the room - which may be humid. I noticed when last in France that they sometimes clad external chimneys with zinc to provide a rain screen as it is virtually impossible to otherwise prevent damp to a chimney breast which is only inches below a saturated stack.
Great advice, I’ve got a chimney with exact the same problem. I’ve checked the flashing and all possible issues for Water to get in. I’ve even added an extra event in the chimney to create more airflow. Mel has worked. The chimney is at the corner of the house so therefore there is no possibility for water to evaporate before going into the house inside the roof void.
It looks like I’ll need to use storm dry to stop water getting into the brickwork in the first place. I have damp problem with two out of three chimneys all in sum on positions. The puzzler but I’m feeling that storm dry is the only option available, which I’ll do this summer.
Thanks for the insight.
Aidan
Interesting, i dealt with a stack with saturated bricks, even in the middle of summer with flashing that was fine etc. stack had been used to burn coal only all its life, my conclusion was that soot attracted moisture and kept the bricks wet all that time. In the end the stack was removed and the lower brick was coved with a independent stud wall with plaster board.
This house is made from Yorkshire sandstone delph walling, the house next door has been sandblasted. The pointing is way to strong for the stonework, eventually this strength of mortar will destroy the stonework with freeze/thaw, you can’t see all of the chimney, he needs to get up to the roof to have a proper look.
Thank you for that, I thought it was stone but changed my mind. Sandstone makes sense and you are right the pointing is going to do a lot of damage
@@SkillBuilder keep up the great videos Roger!
I'm a builder and looking at the stain the back gutter looks like the problem. If the apron flashing upstand is anything to go by I hope your back gutter has a better upstand.
Just thinking about that pointing, might not apply here but I know with Victorian London properties a lot were flushpointed, so the water just runs down the face. That pointing there looks proud, will it pool water and the porous sandstone will absorb it? Try flushpointing in NHL 5?
It could be in Lancs and the house next door is painted. All the houses in Yorks and Lancs are pointed with OPC, but to be fair, most of the time it doesn't damage the house at all, it's very rare it does.
I got fooled by a damp chimney breast. I went up & repaired the chimney rendering, checked all the flashings, ventilation cap etc. And what it turned out to be was hydroscopic salts from 90 years of fires had saturated the fabric of the chimney. So in damp weather, it attracted moisture just as leaving a bowl of table salt out does. I largely resolved it simply by painting the chimney breast with Stainblock & ensuring good ventilation through the unused chimney to keep it as dry as possible.
Normally I would be critical of siloxane treatments as I am not convinced they are a good idea, however I have used them in a very localised manner and found they can work where all else fails. My advice is don't go to the siloxane as a first port of call as repointing in lime should work, but as you say it might need a bit more help?
A point worth making is that traditionally chimneys were always in use and this kept them dry, but today they are rarely used and just get wetter.
good video roger !! looks like its leaking at the back of chimney as the water marks on the ceiling is a telltail sign and can definately leak by the silicon holes by the flashings !
by the stains on the plaster first place i would look is the back tray
same as you mark and just check the soakers and pointing
cant under stand how 4 roofers and so many comments cant see this
as water runs down wards think by looks of the pointing just bad roofers
chimney being damp normally would show on the plaster on chimney breast in bedroom below ... looks like its coming either through a cracked or missing slate above chimney or more likely poor / damaged flashings around chimney. Far too strong a mix used on the stone work ..would of been better to use a lime mortar. There's premixed lime mortars available with lots of colours available now that helps make it a fairly simple process.
Just read what Richard Harvey wrote and agree 100%. well done Richard for a well written explanation 👏
Really useful video. I have been working my way through the same issue and had decided to use Stormdry next summer. Stupidly I have closed off the chimney to stop the draught in my lounge. So will also open up the chimney (hadn't thought of that before seeing this video).
As you have already hinted at it would appear the damp is trapped within the internal finishes - easy to say but it is advisable to open up internally , inspect and allow to dry out.
Hi Roger,
Are the chimneys still open and allowing rainfall to enter?
Are the fireplaces closed up?
You know the rest.
Love the channel
At 2:18 to 2:40, I can see that the chimney is leaning to the left; while pretty much square to the roof it isn't vertical. I don't know if that's a cause of the dampness, an effect, or just a red herring, but it doesn't seem right.
The lead flashing on the side don't overlap each other for my liking . As said a water seal would help if nothing else is done , simple DIY job too
Could need a lead tray in the chimney and repointing in lime also vents in the chimney would help
I had a similar issue ... builder up and made a mess of my flashing which was as far as he could stretch basically, to no avail....popped an old camera on a fishing rod and filmed the very top from a safe ladder height, around the pots and found the crack across the cement cap...bought a scaffold tower and fixed it myself...solved. just need to start from the top, not just where you can get to...
Very pleased to see you now recognise cement mortar traps in damp whereas lime will help damp escape.....
I have been saying this for years.
I've also noticed the gaps in the fibre cement slates, depends on where he lives & which way his house is pointing he could have water being pushed up under those slates. basically like a capillary action. If he finds that most of the time the wind blows over this side of the roof then there's your problem.
Lots of logical comments been made already, but the colour of the staining indicates mineral contamination which is probably very hygroscopic and possibly will never dry. I’m a damp surveyor and I see this hygroscopic damp problem a lot below old chimneys. I’ve seen perfectly good chimneys removed completely and tiled over, but the damp patch below still never dries. I think it could be part of the issue here.
1min 30 seconds in ….,thermal image the chimney breast & take photos
Then garden hose out of the loft window & saturate the c/Breast ….thermal again
Depending on outside temperature & fabric temp ….you should see something
V difficult (but we have done it) connect G/hose to hot water from combi & spray area with hot water
You then have the cooler brick work + hot water / now you have a larger temp differential….easy to find weak spot or spots
Wow that is very clever but I have a feeling it will get me into hot water.
I remember you on the Richie Allen show!
I’d say there’s an issue in the leadwork behind the chimney, water is pooling on the plasterboard at the back of the chimney and then running down the side of the chimney, the watermarks tell the story. If the chimney was allowing water to permeate through there would be a more even spread of a visible damp patch and watermarks whereas in this occasion it is concentrated at the back of the chimney and then finding it’s way down the ceiling alongside the chimney.
Is the cement round the pot cracked?
New lead work is needed, new front apron side flashing and back tray are needed
The rear of my house faces the weather - wind driven rain - and I gave it a coat of storm dry and I swear it even made the rear rooms warmer as well as waterproofing the wall, all for a couple of tubs of it!
Water will allow temperature transfer. Dry material won't half as much. Dry the wall and you're keeping the heat in!
In the future you need to give out the area of where these houses are because not only might there be someone there who could fix it, but also local knowledge (of weather and materials) is very useful. It would also be good to know where the most winds are coming from in relation to the leaks. It looks to me like a North Eastern Lancashire house, possibly Colne or Burnley, somewhere round there. WDR and porous stone is a big problem in that area and the fact the house next door has been painted says something. I would agree with Stormdry, but need to warn you of something. If it's done with that and then needs repointing, the pointing won't stick! That is if it's managed to soak into the joints, maybe all that horrible strap pointing will stop it. The other thing to note is that some of the houses out that way (Pennines) get so much WDR that it even gets through Siloxane, wets the wall and still runs in.
I have a house near Accrington which was painted when I bought it almost 20 years ago, and quite damp Had the front wall (of stone) sandblasted a few years ago and the wall has dried out and remained dry since. Painting or rendering don't always do buildings any favours
Easiest thing would be to take down the damp plaster area and expose the chimney from the inside. Dry the timber and wait for the next rain fall, find the exact spot where the water is coming in.
Surely water can track all over the place making it hard to know the exact entry point or give red herrings?
@@alexp1054well there is gravity, which means everything flows downwards. Far easier to remove interior plasterboard , than put someone on the roof. You might even get lucky. On a sunny day, there might be a chnk of light . Especially if you put a blanket on the window and close the door into darkness.
@@Jeremy64444 you forget capillary action of water. Just because water appears in one location visible to the observer, it might be entering at a totally different location, sometimes lower than seen. But your idea is a good one because it will allow the moisture to dry once the area is uncovered.
@@0skar9193 capillary action will leave a trail. Entering at one point, finishing at another. You still will have a track. Use a sunny day to check for sunlight. Use a day of high rainfall to check for the leak.
@@Jeremy64444 Like it.
I agree with you, the chimney has had various efforts but attention to detail is the key, the pointing is hard sand/cement (I would use lime mortar) and lead mate in the flashings is good as it dosnt crack with the movement of the lead during temperature change but I would like to see it fill all the joint (look a bit inconsistant/ gappy) as theres no damp course in this I would plumb for sealing it with storm guard or similar and make sure the flaunching is sound on the top with no cracks and fit a vented cap if not in use.
You have to remember these bricks have seen it all in terms of "weather battering" and are likley to be very weathered.
Chimney is only single skin with a draught going through it (if its an open fire place) so vent it and seal it
I aggree. You shouldnt have any more issues.
👍
Check,back gutter for leaks,rake out and repoint chimney with weather struck joints,make sure top and corbel course are correctly flaunched,cap and vent any unused flues and maybe hack off internal gypsum plaster and use lime instead? Hope that helps?
Sorry Roger - not bricks... Yorkshire stone. I had the same problem with my back gutter. Replaced it, but still got water seeping in when the wind drives the rain against it. My chimney is brick. Eventually I gave the whole chimney a coat of that silicone cream. That solved it.
I said I wasn't sure so thanks for the information.
It's sandstone. Local sedimentary stone.
@@SkillBuilder No problem, I wasn't having a go - just giving the info. This type of stone often delaminates to a degree. If you look carefully at it, it is made up of thin layers of sediment (as Edward has pointed out.) What can happen over the decades is that water gets in between the layers, expands as it freezes, opening up the gap between the layers of sediment very slightly. Once that has occured, water will subsequently be drawn in by capilliary action; it doesn't 'soak' through - it's actually pumping it through. I've seen a case where patio doors had been put in a wall in an old Yorkshire cottage, without a tray. Water poured in above the door, when rain drove against it. Our boss told us to give the wall a coat of DPC silicon (long before this paste came out.) We scoffed at the suggestion, but the boss is the boss 😉. It cured it permanently. completely, so
It isn't just to strong a mix it isn't weather struck, the top of the pointing protrudes past the line of the masonry and it should "tuck" under it.
Aside from that the flashings aren't great and if the chimney isn't used some damp could be internal.
I wonder if the chimneys blocked off with no air vent You can get condensation building up inside the chimney stack what do you think?
Open it up and get some airflow
Iv got the same problem and have been thinking of using stormdry on my chimneys after good results on a damp wall
Hi Roger . One of the potential problems for owners of older properties like me where sand lime mortar jointing dried out excessively due to last years drought . Unfortunately this led to wicking effect . So with the joints getting soaked by rainwater the internal walls can not dry out fast enough during the winter months . We therefore have to wait for the summer months to dry out the rooms .
My chimney was leaking when it rained due to the bricks being very porous so I tried a version of siloxane yogurt stuff which worked a treat. The bricks in the loft were soaked previously but are bone dry now.
Worked on these for years. Its the soakers they aren't overlapping they aren't long enough. The flashing isn't overlapping enough too. Agree with the storm dry on these old stone houses they have been up 120 years sometimes every little helps. Should see lead poking out of every slate at the side of the chimney
I could really do with your expertise, I have a problem with my chimney, I have had several people try to fix it, but every winter, sure enough we get some damp on the ceiling, flaking paint on the ceiling, salts coming out of the plasterboard and wall.... definitely want it sorted out, Croydon based here. The chimney is part of an extension that was built in 1996 and has apparently never been right!
We have had chimney scaffold up for two years. Had the pots capped, pointing repaired, stormdry applied. Still a slight damp issue. All the lead looks good. My neighbour and myself are wondering if the lead valleys have become porous. The house is 80 years old. However, it's an ex council property and the council replaced all the roofs in the 70's and sprayed foam insulation into the cavities. Next step is to check all the copper pipes in the loft. Work has been done and we know that in the 70's cheap impure copper was the only tube available and it was contaminated with particles of iron. The iron rusts and small pinholes appear. It's been a nightmare.
Could be water going down the chimney pots. A few builders misdiagnosed damp spots around my chimney.. Suggested I needed to scaffold the whole house and take them down. A new £30 cowl fixed it.
The culprit is that pointing job! Someone used a strong mix of cement mortar and cement will retain water for a very long time. Also as @MrDimensionalStone said the pointing is way to strong for the stonework, so it will crack over time and water seeps in. He probably has the same problem in outer walls but insulation prevents from going to inner walls. He should also check the top (flat part) of the chimney. I live in Portugal and for many years people used to restore old houses with granite walls repointing with cement mortar. This led to problems with water ingress and cracking. These days we use lime mortars compatible with the stone.
Warm flue and a cold flue can cause condensation. Have seen that run like a tap before. Not saying its the case here but that one will get you scratching your head. Took a chimney down twice on that one
Think there's a multitude of problems here.
Pointing for one, never had any faith in cement strap pointing. All it does is cause damp and over time, damages brick as we can see in some of the photos. If you visit houses with that kind of pointing, I would wager that all have damp.
The stepped lead flashing needs tidying up properly. Do we even know if that flashing is rolled inside the mortar joint or is it just pushed in flat. The apron as you say could have done with being up at least another course.
Mortar on lead does not seal effectively as water will travel through the mortar and where the mortar meets the lead.
I see something that resembles a join between properties, I would be having a look at that aswell.
Great show old man may God richly bless you thanks 😊
I have exactly the same problem! Six different roofers have not been able to fix it. I have a pet paddling pool in the loft catching the water. Am at my wits end after having so much done by different contractors and paid so much. Fed up. How can so many professionals not know what the problem is!
As an architect the pattern of damp emanates from the rear of the stack. Ring wind can hold a 100 mm head of water and a lot of water is hitting the back of the stack and running down onto the back flashing. I would replace the back soakers and flashings ensuring the lead has as deep a bed as possible. Then treat the tack with a sprayed waterproofed or render the back face. With waterproof render.
Hi Roger, if this person doesn't use one of these flues they need to make sure it is vented top and bottom or this will cause big problems as the air oassung by helps ti wick the moisture away 😊👍🏻
There are no caps on 5hose crown type chimneys! The water pours in , hits an internal shelf and there it is , but there's sometimes multiple issues
🧐🧐great video mate i had similar job two years ago ..after replacing all lead work and felt batten etc correctly it was still coming back on bad heavy rain showers. on second attempt i did all repointing and could see The problem ..on removing the old cement it was getting behind and most bricks were saturated finally had solved the problem
I live in a cottage built in 1820, water running down chimney in loft. The bricks were soaking water like a sponge. Stormdry solved the problem. Fantastic stuff. Goes on white and creamy but soaks in and then after a day or two you'd never know it was on.
Just plain Laminating epoxy Resin works well, To arrive coat fibreglass boat hulls and Cast iron Keels 3 coats does the job at a fraction of the price of Barrier Coat from Chandlers. Silicon DPC Would work on Bricks and be even cheaper. would work on porous stonework as well. Just paint it on until it stops absorbing any more. It's used for putting a Damp proof course into Stone Walls by pumping it in up to ground level, 5 gallon Drums of it used to be a reasonable price. The problem with Bricks , clay tiles Ridge tiles and Finials is they aren't fired at a high enough temperature, so the service life of Facing Bricks for example, is they have a service life if only about 400 years before going porous, and a lot less if the manufacturer drops the Firing temperature to save a lot of money. There are manufacturers who do fire at the correct Temperature but for things like ridge tiles, they Warp, so users need to be aware that a bit more effort is needed to fit them so they look nice, worth it for the much better product though. If a customer bought a roof off me, in Natural Slate (which I specialised in ) I usually earned a nice profit on the Foreign Exchange Currency Purchase, to give them a nice discount on the overall Roof Package , and with assistance on getting things right, it was amazing what a good job DIY refurbished could turn out, and for a lot less money than getting a Cowboy Roofer to do it, all it took was instructions when they needed help, plus Brain engaged and Patience. That was probably the most job Satisfaction I've ever had, and years later, going past their Beautiful Roof, is a heck of a buzz still. Best Wishes. Bob. 👍
Got a leaky chimney possibly and it’s been given plenty of coatings of modern stuff. Hoping I can get a builder to use lime for rebuilding the chimney.
Sounds like very sensible advice to me as all external finishes should allow evaporative drying as you rightly point out. Also he should indeed follow your advice an have the back-gutter checked. If the flues are disused I might also suggest fitting pepper pots to these to prevent rain going down the pots. Rain-hoods would be an alternative if they are in use. That pointing is wrong practically and visually as you say!
I lived in a house for 25 years ...had the same problem . Had all the local roofers take a look and spent thousands. Had it repointed ....new flashing and water seal . It was still leaking when I moved house !
Quite a few things could be happening there, hard to say from brief pics, but maybe even water flowing along the ridge under the tiles from a neighbouring roof? I think I'd try a process of elimination starting by tying a tarpaulin tight around the chimney to see if the water is really coming from there? Though repeat visits will get expensive for the builder, I suspect, as people like an instant correct answer.
The pointing is the issue more than the type of sand and strength they have used. Pointing should sit just under the brick above it and chamfered to create run off. That pointing is trapping rain water at the top of the pointing due to it coming out further than the brick.
Roger, I notice that there are no chimney cowls so water entering the stack ?. Is the stack servicing a fire that's regularly lit during winter and is the fireplace made up ? Apart from that a few open apertures around pointing and flashing to be filled, then as you said, a good coating of Storm Seal applied in summer when the stack has dried out. Owner could do this himself with not too much expense.
Is the chimney still being used for a fire? In times gone by when it was cold or wet the fire would have been lit and the heat from fire would have warmed up the chimney and driven the damp out through the bricks. If the fire is no longer used the chimney should be capped off with a ventilated pot and vent lower down. When the bricks have dried out use Storm Dry as you suggest.
either soakers don't start far enough up or back gutter is inadequate ! can't see the pointing being the issue...
though it isn't ideal and would be worth weather pointing if you are accessing the chimney anyway.. a brick treatment is a good idea as suggested but I still feel there is a greater problem on the back flashing!
Loft conversion with almost certainly no lead or damp proof break between exterior or interior chimney brickwork. Pointing and brickwork suffering from osmosis and transmitting damp into loft space that is now a room, not a vented roof space. The cold and damp brickwork is now almost certainly cold bridging and attractive humidity from the house and rooms below, adding to the damp plaster. Just my opinion.
It's not a 'conversion'. Lots of Victorian homes were built with purpose built loft rooms, which is the case here
@@gypsygem9395 Okay.
I often find a chimney rebuild with a lead tray. these old stacks were often built without them and were ok while as the damp had a metre or so to dry out in the attic.. the problem cmae when the attic was converted into a room and not allowing the damp from the outside to dry out.
I would say a problem with the back flashing. Or wrong instalation of roof felt with water actually coming from further up the roof then depositing at the end of the felt run
It’s salt damp a salts analysis test will prove it. So it’s hygroscopic salting attracting moisture from the internal air. It’s very common. A client of mine spent thousands and even had the chimney removed still same problem. All spent unnecessarily it was salt damp.
I am a damp and timber surveyor.
Looks to me like Bradford / Halifax / Keighley area. I suspect the soakers and back gutter. As built these had a very narrow & sloping back gutter, so when you replace the slates you can't just bang in new lead, it needs new wood under to support it too. It looks to me like the rear gutter has just been 'bossed' that's to say formed by hammering it, rather than lead burning (welding) it. I suggest get a proper roofer to strip the slates then replace & / or inspect the soakers making sure they are fixed to the batons and are the correct height & width. The step flashing front corner requires replacement as does the pointing, as mentioned. Lastly the back gutter may need removal for full inspection as even pin holes can be enough to cause a problem. The back gutter upstand itself should be covered by a flashing pointed into the stone ( yes, it's stone) at least 4" above the flat part of the back gutter.
You are spot on with all that and yes when I looked at that back gutter again it does look a bit rough. Bossing a back gutter is not wrong but it has to be done properly and not just with your boot. Also the fact that the roofs run downhill means the angle of creep is more.
Bossing, if done properly, is probably superior to lead burning, but the latter is an easier skill to learn to do right.
@@RicktheRecorder Interesting, as a welder & panel beater in a previous career I would say welding lead is a tricky skill to get right... bossing for me would be the way to go but it needs to be done properly
@@0skar9193 Lead burning requires a knack, but once you have it you can make any shape with equal ease. Bossing requires different skills for each shape.
@@RicktheRecorder the relevant process for the required need?
The chimney on the right hand side is also pointed in the same way, Probably a pin hole, or tiny crack in the lead at rear of the stack dripping on to the timber support board beneath. Lead goes thin when beaten to stretch around a right angle ,plus age and degradation. Staining on the ceiling is mainly to rear and tracking down part way.
If the internal fireplaces have been blanked off they must be ventilated or condensation will produce this problem . I would want to know what the chimneys are now used for .
Roger didn't mention much the other reason that pointing is so bad in this situation- it holds the rainwater. It doesn't alow the water to flow off well so it kind of hangs about on the brickwork much longer than it should. The stack needs everything possible tipped in it's favour if it's not going to leak.
Seen same problem..the entire stack looks saturated due to the pointing actually channelling rain in and poor silicon job - it will refuse to dry without some help! Solution was to rake it right back, check soakers etc then put a temp breathable roof felt covering over it and make sure its venting well then let it dry out over summer. Once dry weather struck point with soft lime mix
I agree with comment below, lead work looks substandard, take the lot off and start again, can spend a fortune on people jumping up there with a mastic gun. A good roofer who can weld lead will have it sorted for good! Just my humble opinion as invited to offer.
Lead work doesn’t look great but I have seen issues where a cracked cap caused issues like this and also had issue with some bricks just absorbing the the water and it’s coming threw them below the lead. Few coats of Thomson’s or a worst case render it with sand and cent with added waterproofer. That’s my personal opinion.
Replace step flashing, back gutter, apron,seal with Lead sealant then coat whole of stack with storm dry , job done.
Look at pic on page 8:09. There you can see each bit of flashing is basically a narrow sheet of lead that barely extends to the left beyond the margin of the next section of flashing. This allows water to creep along in that overlap, then migrate further inwards to the brick. Those sections of flashing should have their entire face be shaped like a triangle with the top going into the mortar, then the next section coming down over it, not leaving unflashed small sections. There lies the source of the leakage problem - bad, incomplete flashing sections..
Totally agree. Also the general 'quality' of the flashing would make me suspicious the soakers were inadequate as well.
I can't help but wonder if the perpetrator of the ribbon pointing was also responsible for the leadwork?
Maybe the water ingress problem has been fixed and what we are now seeing is the stain coming through the emulsion paint. From what I can make out it looks like it could well be that. Easy way for the homeowner to test would be draw around the stain with a pencil. Wait a couple of days after a downpour of rain and check your pencil line. If no change to size then use a stain block paint in that area. After that emulsion the area as normal. Obviously I may be wrong but thats why I say draw around it and check first.
havnt read comments chimneys are built only single skin brickwork if no longer in use never get chance to dry out fully if not in use need to be capped off and air flow introduced most commonly by the addition of air bricks
I've got a soaking chimney a black water goop twickles down the inside of the chimney making a huge mess at the bottom. I've repointed twice, weather shield it, and put loads of roof repair paint from the leading to the damp proof lining and coated the top around pots for good measure but still no improvement. It's a flued lined chimney. Should I put a breath brick in up there? Also, how do you dry it? Lighting the fire does it but the wet returns. Yours desperately!
I used Integral Waterproofer on a 1 to 20 mix in water with my sand, cement and lime. Also a bit of SBR and Rendamix for this external render
First try the Thompson's water seal or some thing similar. If that does not work Then Re lead the stack, Bell cast beads around the base of the stack, scratch coat , render and re flaunch the top of the stack with wash sand cement or if the chimney is not in use then drop it below roof line and felt, batten and slate over the void!
I see this regular I would say its 90% that its Cold(Thermal) Bridging causing condensation on the restricted ceiling space with all the moisture in the house rising up to the converted roof-space.
I have a very similar problem. It seems like the brick is soaked and went black with damp. Flashing all looks sound. Had a guy come and look at it and sand blasted the brickwork and repoint. Now its exactly the same state. I figured getting a pro in was the best thing to do as they'd sort it quickly rather than me take time off work I'll be going up to clear it up myself now.
I'd absolutely agree with the Stormdry treatment. Also what about the haunching and pots? Is the haunching cracked and crumbly? Are the pots still used and if not have they been capped against rain ingress (with ventilation of course!)
I get why you'd cap the pots but what is the ventilation for and how is it installed?