Don't these vents lower the structual integrity of the roof? What do you mean by staggering vents? I recently purchased an older house and started with insulating the attic, now I have a dump stain on a freshly painted wall which faces the elements. Condensation was my second thought after issues with pointing. Solid walls, no cavity.
Had so much condensation in my loft it was dripping and pooling on the boarding and soaking the timbers. I installed 20 lap vents and fitted a new loft hatch seal. While initially skeptical, it has solved the problem. Within a few days the condensation was gone, and a week or so later all the timbers were dry. Pretty impressed I was able to fix the issue for about £50. Normally these things cost you hundreds!
that is interesting. you mention a loft seal do you have a proper loft hatch. mine is a plank of wood sort of, that i have adapted so i can put insulation in it. thanks
Far and away the most down to earth, sensible video on this very common problem. 50 yrs in the building trade, (joiner, not roofer,) and two years ago, I decided it was time to underfelt my end of terrace, hipped roof. Westmorland slates, no back pointing and no fascia and soffit before, so plenty of ventilation and never noticed any condensation, except in extremely cold weather, on the underside of the slates. I used the best breathable membrane the roofing firm recommended, and assumed I'd have no problems... Until I went up to get the Christmas tree down from the loft, a week ago. (seems to be the time everyone notices it,) and noticed a musty smell. Looking up at the membrane, it was covered in beads of condensation, In a few places so much that a few drops had landed on a couple of cardboard boxes, and was wetting the sides of the rafters. To be honest, I'd never seen these lap vents before, and I was just about to order a dozen or so soffit vents and wasn't really looking forward to drilling the soffit at the top of a triple extension... I'll certainly give them a try first off. As you say though - there are some situations when no matter how much ventilation you have, condensation will occur: such as this last two weeks, when we've had that high pressure block over Scandinavia, the temperature plummets to below zero, and there's not a breath of wind.
Johnriggs, yes indeed, seems like old school is the best. Even with just the old lime mortar torching/sarking/tiering you would still have tween-slate moisture evaporation etc, so maybe putting felt/breathable membrane under good fitting slates is itself a step backwards in this respect. My Burlington blue/grey circa 1912 roof has no felt, has open apertures at the eaves, and all is OK. I've just been up there now, 1.3 degrees C outside, wind rain and sleet, slates cold to the touch but not wet or dripping or anything. Sure I could get a wasp or bees nest in, but it has never happened, occasional drip when wind and rain work together in a certain direction or something once or twice a year, but most of my issues are simply down to the inevitable nail-sickness and weather worn antique slates. I am going to soon get it reslated so I am contemplating breathable felt, or no felt at all. There is the potential of snow ingress under the slates of course, which is what the lime torching was all about in the first place.
Thank you so much for providing a cheap solution to a potentially expensive problem. Humidity down from 88% to 57% in 2 days. No need for a roofer or builder. Our neighbours will be looking at this with interest.
Daniel thank you so much for your advice my loft was raining inside pools of water mold items getting damaged. Realized that the radiator on the landing was pumping heat straight up into the loft via a poorly fitting and badly insulated loft hatch.New super insulated door £40 box of 30 felt vents like you demonstrate, 45 minutes later job done. Air flow is amazing 3 day's later completely dry first time in years cheers mate much appreciated. 5 Star advice.
Thanks for putting my mind at ease! I'm in year 1 of living in my own house and panicked when I discovered some condensation in my loft yesterday (even though it's ventilated). Learning that a little bit of condensation is normal, especially during a cold snap, was calming to hear.
I've been having sleepless nights over condensation in my loft, I have just ordered some from Amazon and keeping everything crossed they work. Thank you.
Thanks for explaining that some loft condensation is normal especially on very cold, still days like we've seen this winter. This is the best video I've seen.
Best video on this I’ve seen. We’ve got the same issue, about a meter of insulation and stuffed right into the edges. Loft is full of condensation and our bedroom window is soaked every morning….. this is just what I needed to see 🎉
Great information, cheers Dan. My daughters Edwardian semi has this exact problem. Her roof space is absolutely dripping with condensation in cold weather situations. Going to buy and fit a dozen of these for her. Thanks again.
Thanks for this, super helpful! Went up to the loft to find an alarming amount of dripping condensation after fitting new insulation in an end of terrace house and then the weather getting cold. This has reassured me how to address it and have ordered the vents so hopefully all will be well!
Great idea. I will be ordering and fittin some of these straight away. Not sure but the condensation has become more of a problem for us since having a wood stove fitted. I am sure the chimney being warm in the loft has contributed along with the lack of ventilation in the roof. No soffit vents or roof tile vents in our 60 year old roof. Old roof felt that does not allow vapour through doesn't help either. Most modern roof felts are breathable and use a tyvek or similar material. Very useful video thanks.
Very informative - we have the exact same problem with condensation dripping down between the felt and getting damp/mould on the ceiling inside the house. This sounds like an effective and cheap solution, have now ordered the vents. Hopefully will sort out the issue, thanks for being a lifesaver
Thanks for posting. this little device that i hope will help with the condensation i have in the loft across the whole width i have only notice it last year and we have been in the house to 22 years, just ordered them so we shell see how it goes. thanks
Thank you so much for this, really helpful and informative and you've put our minds at rest. Was getting really concerned about this before we found your video.❤😊
My bathroom and kitchen ceiling and the walls on the inside are always wet along the windows like its a leak but its only at colder days in winter days i looked in the attic and the felt on the inside was wet too with drops falling , though i was dumb doing this i thought it was because the istilation was not right up the corners of the roof edges as there was gaps, now you told me on the video i will pull them back on both sides of the attic and get some of theses vents.
Good quality bathroom extractor fans come with a built-in sensor that switches on the fan when the humidity level is too high in the bathroom and automatically switches off when the moisture level is returned back to normal. I always recommend these to landlords as some tenants never open windows, and they are very effective. Also, you can buy a humidity sensor from Amazon for about £10 and take readings in all your rooms over several days. If the moisture content in the air is consistently too high (above 60%) then you may wish to consider fitting some window trickle vents or something similar to get it down to 40-60%.
If the humidity level is too high, you may see excessive condensation around window frames and in the loft when it's cold outside. You may also see mould spots on walls and ceilings and experience a tickly cough too. Installing loft vents (and unblocking any existing ones) will certainly help reduce the condensation in the loft but in extreme cases where there's too much moisture in the home making its way into the loft, some trickle ventilation in the house can also make a big difference. You may find this helpful, it's written for tenants but the advice applies to everyone - www.oxford.gov.uk/info/20271/guidance_for_private_tenants/1129/preventing_damp_and_mould
@@diygardeninguk ok thianks, i have one of the extractor fans in both the kitchen and bathroom but its still do`t help i even open windows, i will try clearing the roof vents in the edges as you said may help the problem.
Did my loft BUT having installed the vents at one level of felt, when I tried at the lower level there appeared to be a batten going the length of the loft with the felt tight to it, no way I could get the vents in, so largely felt I'd wasted the money as there's no through draught.
I fitted these lap vents several years ago and they have transformed the amount of air flow in the loft. However you still need to deal with the root cause of condensation. In my case after several hours of investigation, I found that right in the eaves of the loft it hadn’t been insulated allowing warm air into the loft space. It’s was tricky because I didn’t want to block airflow to the vents in the eaves. Anyway it cured the condensation and now I have a nice dry loft with plenty of airflow
Yes, you are 100% correct. I've also seen homes where downlights have been fitted into the ceiling and the insulation has been pulled away to prevent a fire risk, these gaps have led to warm moist air getting into the loft. Also, when it's cold outside, most ppl put the rads on and keep their doors and windows shut so the humidity in the home skyrockets and when it touches icy cold loft felt, it deposits litres of water droplets.
A lack of insulation should not change the amount of water penetrating through the plaster ceiling. Indeed, the insulation may cause it to be trapped within the insulation instead of venting.
In addition to water vapour coming up from the house it can also linger in the loft after warm, humid weather which is suddently replaced by night frosts when there's no breeze to replace the humid air in the loft.
Thank you for this video, you have really put my mind at ease and I'll get some of these vents. I went into the loft today to get some Christmas presents we had bought down to wrap and there was a lot of condensation on the felt and some drips down the middle of the boards as we have had our loft boarded (properly using loftzone) I was very concerned, however my fiancé had recently had a bath and we also have badly fitted down lights in the bathroom. I will check on it and fit the vents and hopefully all will be okay. Its also incredibly cold in the UK at the moment.
I had exactly the same. I installed the vents, fitted a new loft hatch seal and made sure to crack the window open when having a bath/shower and it fixed the problem almost immediately.
I seriously wish you lived close to me as we have so many issues with our roof and loft. So far l have spent 5k and we still have problems. I am so stressed about this as its been going on since February. I live in Cambridgeshire and struggle to find a roofer who is genuine. Any ideas l would be so grateful.
If you have a vented central heating system, please ensure the feed and expansion tank (also called the header tank) which is a small cistern in the loft supplies the central heating circuit with water and accommodates the expansion of the water when it is heated by the boiler) is well covered and insulated.
We had this after a loft conversion. That old black felt is absolutely a menace as it doesn't breath, we added these vents after the fact as we still had ceilings to replace. Unfortunately this winter has made the issue come back due to the very low temperatures.
Dad i have a wet loft .......like the one you have just shown us ..my daughter contacted her landlord and was quoted £1500 to put it right ..So i machined a load of wedges from a plastic called Stockboard. approx 150mm long and tapering from25mm to 0mm . inserted these exactly as you have ..cost £25 ....the loft is now bone dry ..didn't even get a thankyou from the landlord ,,(I'll take them out if she ever moves house )
thanks daniel , we got the condensation ,we got a few drips, so will be going to have to sort out , ,at the moment lots of various goods up there and my cloakroom distractor stopped workin 3 yrs ago and upstairs bathroom 2 yrs ago ( naughty boy) . we have black patches or spotting on ceiling just under the eves front and back rooms IS IT A LEAKY ROOF FROM POROUS OLD TILES OR IS IT something else ? ps live in end of terrace sim to yours
Got 10 plastic vents and 4 tile vents - 2 each side but still getting issues on very cold days. The soffits are asbestos board than have been capped over so no ventilation. It’s like to put more ventilation in from eaves but how would I do this if I can’t touch the asbestos?
Thank you very much. Really informative and I'm just about to order lap vents to solve my loft moisture problem (due to the current cold spell) identical to the one you describe.
Thanks! Really helpful. Silly question, but I couldn't tell a cowboy builder from the town Sheriff 😞: If I wanted to get a professional to have a look at improving my attic insulation / ventilation, are there any trade body memberships I should look for so I know they are reputable?
Your videos are amazing, I'm surprised you don't have a lot more subscribers! One question I have. Is this kind of felt lap vent enough for the entire roof, or if I'll have loft insulation put in, should I pay for that proper vent as well that goes through the roof and can be seen from outside?
hi, thanks very much for this. I am doing my own loft insulation. There is already about 100mm of loft insulation from the previous owner (they must have done it back in the early 2000s). I will top these up after inspecting them (and replace where needed). A question I have is: do all roofs have that vent on the side of the roofs like you mention at 03:16 ? I can't really see mine as there is a slope and it's hard to get underneath it with on lying on my stomach, and also the old insulation is in the way. What am I looking for? thank you
Great video, thanks a lot @diygardeninguk. I realized lately that my roof suffers from condensation and has no ventillation system at all. I will start by installing some of these lap vents between the underlay sheets. My roof doesn't have any vent tiles or eave tiles at all so would you recommend still getting a few of each (to cover bottom and top) installed by a professional? Just wondering if the lap vent will be enough on their own without any opening at the eaves and top of the tiles. Thanks
Great video thanks very much! I have non breathable felt on and just had 90mm eps external insulation attached to my solid walls. So disappointed with it as all it's done is contained and increased moisture into the house and now has nowhere to go except the roof. I'm going to install loads of these vents myself and then also attach a breathable superquilt foil to the roof rafters. I'll leave the last ones unstapled so can check up if the moisture is escaping clearing. Would that work out OK though? I had a roofer guy round and he suggested I pop few roof tiles off and install vents at quite a cost but going to your options first
The lap vents will work just as well as vent tiles, just cheaper and easier to install, so I would start with those. If the new external insulation has reduced the breathability of the home, then can this be improved by installing or upgrading the trickle ventilation in the home? (less moisture in the home = less getting into the loft). This should have been predicted and trickle vents specified by the insulation installer at the design stage of the works (I'm assuming that the original walls were breathable and the eps has reduced the moisture transfer rate). R.e the "breathable Superquilt", this will require an airflow behind it; between the rafters at both the top and bottom of the roof - this is usually achieved with eaves vents and a ridge vent but I can't see why the lap vents wouldn't achieve the same result. However, I would first contact the manufacturer and ask them for advice. If this were my home, I would try to get the moisture level under control via trickle vents in the home and lap vents in the loft before I spent too much on expensive insulation products. However, as I'm sure you can appreciate, I can't see what existing trickle ventilation is in place, nor do I know the humidity levels in the rooms or the materials used in the solid wall so I'm making assumptions.
@DIY Gardening That is good to hear, i can only hope it works. I didn't have these problems until the Eps was fitted. Standard solid walls, the heat was just passing through the wall before with no condensation. They drilled holes in all the double glazed windows and installed trickle vents everywhere so very breathable and letting in more cold! For some reason, the new eps measure has made the whole house twice as cold than before. None of it is making any sense. And Because of a poorly built open plan extension downstairs, the upstairs rooms are now 5 degrees acting like a reverse vacuum, pulling cold heavy air down dropping at night and warm air is accending out of the building. I do have vented soffit and fascia and the eves are clear with lots of draft coming into the loft. The roofer was very puzzled why the the felt is condensing with so much airflow. I am a total layman but assumed it's because that is the dew point and the trapped air has nowhere to go when it hits the felt. I feel the coldness dropping down can hopefully be stopped by superquilt and would also help keep the inside of the felt warmer too preventing it from condensing? Yes there will be plenty gap, 100mm behind it enabling it to breathe. With the vents there, the quilt should give adequate time for the moisture to find a way to escape, all in theory. I have no idea. But true, I need to focus and verify on getting the moisture under control to safety exit before wasting further money. I also have 500mm of fibreglass wool up there. Very confusing how the cold air is penetrating that stuff.
You are likely in the UK, maybe a former railway crossing or former farm workers cottage or similar? The solid wall structure (brick?) would have been of the age where lime mortar was used. Brick and lime mortar together are superbly breathable, but alas now shrouded and 'bagged' by the external insulation system. Often old stuff is best, for whilst cold in winter, it would also be a superbly cool refuge in the fiery heat of summer. Swings and roundabouts. I used to live in an old xing cottage for about 6 years in Suffolk. No elec, no mains water or sewage, just a coal fire and paraffin lamps (1970s), seriously, and winters are cruel in East Anglia, but survive we did, fortifying you could say, single glazing too. It was the norm. Kind regards.
Thanks for the advice which we took but there is still some condensation up there and we put loads in. Cool air - well freezing at the mo coming in so where are we going wrong?
Try changing some of your daily habits to stop the water vapour getting in the loft in the first place. Keep bathroom door shut and window a jar when showering/bathing, especially if you do not have an extractor fan. If you have sopping wet clothes on every radiator in the house, you have to open the windows, to let the moisture out the house. Even if it's freezing outside, unfortunately. If you have a some kind of water tank in your loft, check there is a lid and it is in on securely. Check your loft hatch seal, especially if the hatch is near the bathroom door, it might need refitting/replacing
I have fitted many lap vents and still have a lot of condensation this winter puddles in fact, the problem is one side of the house gets the sun whilst the other is in the shade and its the shady side that get wet, Due cost of electric ( thanks government) i stopped using the dehumidifier but have now fired it up again, the wetness may be windblown into the roof . Having said that you have put my mind at rest, ( littlebit)
Yep although would be somewhat redundant if you’ve already got insulation on the floor of your loft. If putting PIR between the rafters I would recommend leaving at least 25mm ventilation gap between the underside of the tiles and the top of the PIR board to ensure any moisture that gets through the PIR can still be ventilated out the soffit vents and/or the lap vents, else it will condense on the top of the PIR and possibly drip back inside the loft.
Hi, thanks for the informative video. I noticed that all the manufacturers put a warning/caveat about tile up lift and driving rain. I wanted to install some of these in my 2019 home as while I don't ever see condensation in evidence yet the loft always feels damp and musty. I can't find any single source of water ingress or leaks etc. its just generally damp feeling. There is periodically white mould which I clean off with a contact spray. So I wanted to try these vents and noticed that our membrane is a Sandtoft membrane (supposedly breathable yet, it blocks all the airflow from what I can see). They have also been glued together forming a continues layer. If I install these vents low down towards the eves (which also have vents) by unsticking the sections to insert them am I opening myself to a whole world of pain? Thanks.
Hi, we're in scotland where roof installation is different. Got this off screwfix buiders talk - Rafters must be covered with rigid 'sarking boards', a traditional form of timber cladding. Over this base a breather membrane underfelt is laid, held in place by counter-battens and fixed across them. This leaves a ventilated air space under the tiles'. The sarking boards in our attic (new roof done Oct 2022) are moist to touch and think it's condensation. Would these work with this type of roof.
Thanks for the video. I topped up my loft insulation February '22 and now (December '22) by 200mm as in your loft too. I noticed a lot of condensation in the loft space to get the Xmas tree down. I have removed some of the additional insulation I added to see if that improves matters, where it had perhaps been added too close to the corners like yours. I was tempted to buy these lap vents but wanted to understand if they performed in the real world or not. I have solar panels on the roof so adding vents to the outside isn't possible. Could you share your thoughts on how they are performing a few months on from the installation please? Many thanks again for this video
Hi Wobbly Wobbly, i have installed these in my loft and they work really well. I would recommend you put one in every other space between the joists on one side of the loft then on the other side of the loft do the same but stagger the vents so that the vents are not inline! hope that helps
@@FixitwithFowler That's fantastic, just the sort of detail I was hoping for. I'll get them fitted as soon as they arrive in the pattern you describe. Have a great Christmas and New Year
Fox it with fowler, could you describe again the pattern of vents you recommend? I understand doing each side of the roof differently,so the vents don’t face each other across the roof void,but how many vents per each run,between the rafter,top to bottom? If that makes sense I’ve fitted a total of 18 to a roof void 10m X 3m Also fitted soffit vents every 700 mm Reckon that do it? even without tile vents? Great video thanks again
A great product. It wont work on roofs with sarking,( for instance in Scotland). Most roofs in England have no sarking boards and just a dpm and then tile battens and tiles.
Hi mate can I ask your opinion on something? A company phoned my elderly mother just before Christmas offering a damp inspection in her loft. They came out that day and said there was damp in the timber. I've seen the photos they sent of this and the highest moisture level according to their gadget was 14.3%. That was the highest. Anyway they persuaded her to let them install a foil ligning on the inside of the roof itself and treated the timber with an anti fungal treatment. It's not even the thick foil stuff they've used, just regular stuff you can buy in Wickes. They charged my mum over £2800 for this. Then the other week they returned again and said that the loft insulation on the floor (the usual fibre stuff) was still wet and they charged my mum another £2800 to remove all the loft insulation and treat the timber again with some form of anti fungal treatment. The loft now has no insulation bar the foil stuff on the roof and my mum has paid nearly six grand for all this. It's a 3 bed semi detached by the way so not a huge house. I think my mum has been badly scammed here. What do you think? Thanks.
Are you in Scotland? Call Home Energy Scotland to see if she can get help with new insulation. It's called Simple Energy Advice, in England. You should go to Trading Standards and the Citizens advice bureau about the company if you think they've misled your Mum.
They vent out moisture that enters the loft from the home below (cooking, drying clothes, breathing, bathing etc) and are similar to how you may open a bathroom window to vent out steam/condensation after a shower. The reason condensation has become such a problem in the last decade is so many homeowners have replaced drafty windows/doors with airtight double glazing and also insulated/draft-proofed their homes to the point that there's no airflow to pull out the moisture-laden air. The situation has become so problematic that in June 2022, the Building Regulations were changed and now trickle vents must be fitted to windows and doors at time of installation. This will reduce the buildup of condensation in the home so there should be less condensation and mould around windows, ceilings and in the loft. Loft lap vents are an easy and cheap way to vent out any moisture in the loft. Also worth pointing out that all new-build homes come with loft vents (usually top and bottom and permeable roof felts). The Government has published a guide to condensation and in-home ventilation but unfortunately it's very basic - www.gov.uk/government/publications/home-user-guide-template/existing-home-ventilation-guide
Hi Legend27, I have installed these in my loft and had the same problem. I used a paint scraper to gently prise the felt joint apart, then once you side the vent in its worth checking that you can see daylight to ensure they are working!
I think over time the layers can get stuck together. I had a few laps that seemed much tighter than the rest but I just gently but firmly wiggled the vent into place. Seemed to be fine.
I just found lots of condensation that I’ve not noticed before. (Xmas boxes were wet) It’s winter now and I cleared out the loft last year so it’s nearly empty rather than over full but maybe blocking ventilation where what is left is stored? 😬 Also I don’t have the heating on much due to cost? New bathroom? It’s on both sides so I dont think it’s due to anything being broken? If there’s any suggestion if any of these will cause an issue? Im going up to put these vents in today and hope it works. 🤞🏼
Install the vents. Check your loft hatch seal, especially if the hatch is near the bathroom door, it might need refitting/replacing. Keep bathroom door shut and window a jar when showering/bathing, especially if you do not have an extractor fan. If you have a some kind of water tank in your loft, check there is a lid and it is in on securely. If you dry wet clothes in the house, crack a window or two open to let the moisture out. (Water has to go somewhere, either up or out) These steps will make a massive difference.
@@superspecky4eyes thank you! I added vents and checked again (when I put the Xmas tree back up there lol) and it seemed to have solved the problem. I also moved the things stored in the loft so there was more air movement. Hopefully that has helped
Tyvek is a breathable membrane rather than a vapour barrier. Vapour barriers are more like plastic sheets, typically green in colour if you go through places like Screwfix/toolstation to get it.
Hi! We had new fascias and soffits fitted to our 1970 build house last year……the old ones were wooden and these are upvc tongue and groove…..They have no vents! Now after years of living here and never having an issue black mould is growing in the corners of two upstairs rooms…..we’ve had several roofing companies visit and they tell us different things….ranging from insulation to new roof vents ( we havent any )….. the cheapest option was adding roof vents and that was £1000…..and ideas to save us money…we are worried as they have said different things we will choose the wrong one and waste much needed money!
This sounds very similar to our situation minus the mould issues. We have recently had our fascia and soffits done and like you the company didn't install any vents and now we have a sweaty loft. I'm going to try these vents to see if that improves things then failing that I will get some external vents fitted to the soffit boards.
If your problem started with the new soffit and fascia, then that is the way to go. Fit new soffit vents, because if no air can get in anyway then even the felt lap vents will not be of any real use. Probably your 70s wooden fascias and soffits only needed a lick of paint, and everything would have been just fine. Scaffolding and ladders were needed either way, and sure the plastic will last forever per-se, but the roof it is attached to won't without cross-flow venting, and the quality of the accommodation has been thus degraded to boot. Pvc is so often a lose/lose option.
I don't have an attic or loft. I do have a ridge vent and im trying to figure out if i can cover it with shiplap like im doing my ceiling? Or do just leave it uncovered? Which looks tacky. Please advise. Ty
The bitumen in my roof is pulled so tight, the first one I tried instantly ripped the felt. Can't fit them in anywhere. Shame cuz I bought 20 of 'em 🤣 Back to square one now...
Hi Daniel, we have the following problem. We're in a new built house and have boarded 2/3 of the loft. The non boarded part of the loft is dry the boarded one is soaking wet. I know that the guys who have installed the boards were literally walking and sitting on the insulation and they have also cut down the boards in the attic without removing the waste which was left on the insulation. Please tell me if this is the problem (insulation) or it could still be the ventilation? We have boarded the loft in April 2022 and already in October 2022 there was lots of condensation. Now it's so bad that there's black mold. Please advice on what should we do.
Put a pack of 10 Manthorpe vents into my roof space about a week ago, as I had quite serious condensation when I checked about a month ago during very cold weather. Just checked today and apart from a couple of small patches, the felt is now dry looking. I only managed to put them at about halfway and three quarters of the way up the roof, as I am not good with ladders or crawling on rafters! Seems to be working, as there is definitely a flow of air through, as I can see the cobwebs moving. I also invested in a smallish dehumidifier to place next to damp clothes and it seems to be keeping the house humidity down to just under 60%.
Air is already coming through the felt, so what is the point putting in the vents, it is just another product to sell. The problem is the overlapped insulation, which causes the condensation and damp
This nice guy had no condensation issues yet he decided to make his loft insulation worse by pulling them in 200mm and tamper with his loft ventilation. Did he just do it as a hobby me thinks
It’s common sense you need ventilation to prevent damp, condensation etc People these days don’t have common sense 😂 Then you get office workers who look down on tradesmen thinking their dumbasses, when in reality without tradesmen the worlds fucked
Ventilation reduces humidity. Having radiators on, drying clothes indoors, cooking, bathing etc or anything that produces moisture will increase humidity. Condensation in the loft will ease once the outside temperature increases and the vents will stop the loft from getting damp, musty and mouldy. During cold weather periods, I'm careful not to produce excess moisture - I don't dry clothes on rads, I open windows in my bedroom in the morning, in the bathroom after a shower and in the kitchen after cooking etc as this reduces the moisture/humidity in the home.
On the underside of the roof? Then the loft will no longer be cold and uninsulated, it will be warm and no condensation should form - provided the Kingspan insulation is fitted correctly. Lap vents should only be used in cold, uninsulated lofts as condensation can form on the cold surfaces and this needs to be vented out.
@@diygardeningukI’d only caution, based on my personal experience, that the Kingspan should still leave a 25mm ventilation gap between the top of it and the underside of the tiles. I stupidly pushed mine flush and during particularly cold/still spells moisture would condense on the top of the kingspan and drip back into the loft. Now that I’ve pulled the PIR down an inch or so all has been fine.
If you push the bitumen felt up like that, surely you negate the felt's ability to let rain water that's been blown under tiles run freely down the centre of the rafters into gutters? The water will run either side of the plastic insert and you'll have rotten battens sooner than necessary.
Thanks for the easy explanation - great video. If there is a membrane, instead of felt, the KimaAir Inside Out vent can also be fitted from inside (apologies for the plug!) - th-cam.com/video/c1-y0NPIiN0/w-d-xo.html
These lap vents fit most roof felts and can be purchased via Amazon - amzn.to/3W0od9P
Don't these vents lower the structual integrity of the roof? What do you mean by staggering vents? I recently purchased an older house and started with insulating the attic, now I have a dump stain on a freshly painted wall which faces the elements. Condensation was my second thought after issues with pointing. Solid walls, no cavity.
Had so much condensation in my loft it was dripping and pooling on the boarding and soaking the timbers. I installed 20 lap vents and fitted a new loft hatch seal. While initially skeptical, it has solved the problem. Within a few days the condensation was gone, and a week or so later all the timbers were dry. Pretty impressed I was able to fix the issue for about £50. Normally these things cost you hundreds!
that is interesting. you mention a loft seal do you have a proper loft hatch. mine is a plank of wood sort of, that i have adapted so i can put insulation in it. thanks
@@ianrobins5501 Mine is just a plank of wood basically, yes.
Far and away the most down to earth, sensible video on this very common problem. 50 yrs in the building trade, (joiner, not roofer,) and two years ago, I decided it was time to underfelt my end of terrace, hipped roof. Westmorland slates, no back pointing and no fascia and soffit before, so plenty of ventilation and never noticed any condensation, except in extremely cold weather, on the underside of the slates. I used the best breathable membrane the roofing firm recommended, and assumed I'd have no problems...
Until I went up to get the Christmas tree down from the loft, a week ago. (seems to be the time everyone notices it,) and noticed a musty smell. Looking up at the membrane, it was covered in beads of condensation, In a few places so much that a few drops had landed on a couple of cardboard boxes, and was wetting the sides of the rafters. To be honest, I'd never seen these lap vents before, and I was just about to order a dozen or so soffit vents and wasn't really looking forward to drilling the soffit at the top of a triple extension... I'll certainly give them a try first off. As you say though - there are some situations when no matter how much ventilation you have, condensation will occur: such as this last two weeks, when we've had that high pressure block over Scandinavia, the temperature plummets to below zero, and there's not a breath of wind.
Could you advise me how to repair under felt in loft, such as what adhesive I could use as I have some broken felt around vent pipe? Thanks!
Johnriggs, yes indeed, seems like old school is the best. Even with just the old lime mortar torching/sarking/tiering you would still have tween-slate moisture evaporation etc, so maybe putting felt/breathable membrane under good fitting slates is itself a step backwards in this respect.
My Burlington blue/grey circa 1912 roof has no felt, has open apertures at the eaves, and all is OK. I've just been up there now, 1.3 degrees C outside, wind rain and sleet, slates cold to the touch but not wet or dripping or anything. Sure I could get a wasp or bees nest in, but it has never happened, occasional drip when wind and rain work together in a certain direction or something once or twice a year, but most of my issues are simply down to the inevitable nail-sickness and weather worn antique slates.
I am going to soon get it reslated so I am contemplating breathable felt, or no felt at all. There is the potential of snow ingress under the slates of course, which is what the lime torching was all about in the first place.
Thank you so much for providing a cheap solution to a potentially expensive problem. Humidity down from 88% to 57% in 2 days. No need for a roofer or builder. Our neighbours will be looking at this with interest.
Daniel thank you so much for your advice my loft was raining inside pools of water mold items getting damaged. Realized that the radiator on the landing was pumping heat straight up into the loft via a poorly fitting and badly insulated loft hatch.New super insulated door £40 box of 30 felt vents like you demonstrate, 45 minutes later job done. Air flow is amazing 3 day's later completely dry first time in years cheers mate much appreciated. 5 Star advice.
This is exactly the problem I had. Condensation in the loft. Thank you for the advice very helpful
Thanks for putting my mind at ease! I'm in year 1 of living in my own house and panicked when I discovered some condensation in my loft yesterday (even though it's ventilated). Learning that a little bit of condensation is normal, especially during a cold snap, was calming to hear.
Just been quoted £500 for vented dry ridge system. I’ll now stick 10 of these in.
I've been having sleepless nights over condensation in my loft, I have just ordered some from Amazon and keeping everything crossed they work. Thank you.
how did it go!?
Thanks for explaining that some loft condensation is normal especially on very cold, still days like we've seen this winter. This is the best video I've seen.
Best video on this I’ve seen. We’ve got the same issue, about a meter of insulation and stuffed right into the edges. Loft is full of condensation and our bedroom window is soaked every morning….. this is just what I needed to see 🎉
just watched this, exactly describes the condensation I just noticed in my loft
Absolutely spot on mate. I work for a house builder and we come across this problem often.
Thanks m8, mold and some rot, trying to fix it and more motivated to disassemble my soffit siding and install my vents.
Great information, cheers Dan. My daughters Edwardian semi has this exact problem. Her roof space is absolutely dripping with condensation in cold weather situations. Going to buy and fit a dozen of these for her. Thanks again.
Brilliant video. Im just about to install loft legs and board on top so you've given me something to look out for. 😮😮😮
Great video. Bought 10 lap vents - about £2 each. So easy to fit - literally 5 seconds per vent as you said.
Thanks for this, super helpful! Went up to the loft to find an alarming amount of dripping condensation after fitting new insulation in an end of terrace house and then the weather getting cold. This has reassured me how to address it and have ordered the vents so hopefully all will be well!
Great idea. I will be ordering and fittin some of these straight away. Not sure but the condensation has become more of a problem for us since having a wood stove fitted. I am sure the chimney being warm in the loft has contributed along with the lack of ventilation in the roof. No soffit vents or roof tile vents in our 60 year old roof. Old roof felt that does not allow vapour through doesn't help either. Most modern roof felts are breathable and use a tyvek or similar material. Very useful video thanks.
I cut lengths of foam pipe insulation and pushed between the joints, does the job for me.
joints? You mean the lap?
Do lap felt vents worn if solar panels are fitted on the roof….?
Very informative - we have the exact same problem with condensation dripping down between the felt and getting damp/mould on the ceiling inside the house. This sounds like an effective and cheap solution, have now ordered the vents. Hopefully will sort out the issue, thanks for being a lifesaver
Thank you excellent video.
Thanks for posting. this little device that i hope will help with the condensation i have in the loft across the whole width i have only notice it last year and we have been in the house to 22 years, just ordered them so we shell see how it goes. thanks
Thank you so much for this, really helpful and informative and you've put our minds at rest. Was getting really concerned about this before we found your video.❤😊
My bathroom and kitchen ceiling and the walls on the inside are always wet along the windows like its a leak but its only at colder days in winter days i looked in the attic and the felt on the inside was wet too with drops falling , though i was dumb doing this i thought it was because the istilation was not right up the corners of the roof edges as there was gaps, now you told me on the video i will pull them back on both sides of the attic and get some of theses vents.
Good quality bathroom extractor fans come with a built-in sensor that switches on the fan when the humidity level is too high in the bathroom and automatically switches off when the moisture level is returned back to normal. I always recommend these to landlords as some tenants never open windows, and they are very effective.
Also, you can buy a humidity sensor from Amazon for about £10 and take readings in all your rooms over several days. If the moisture content in the air is consistently too high (above 60%) then you may wish to consider fitting some window trickle vents or something similar to get it down to 40-60%.
If the humidity level is too high, you may see excessive condensation around window frames and in the loft when it's cold outside. You may also see mould spots on walls and ceilings and experience a tickly cough too.
Installing loft vents (and unblocking any existing ones) will certainly help reduce the condensation in the loft but in extreme cases where there's too much moisture in the home making its way into the loft, some trickle ventilation in the house can also make a big difference.
You may find this helpful, it's written for tenants but the advice applies to everyone - www.oxford.gov.uk/info/20271/guidance_for_private_tenants/1129/preventing_damp_and_mould
@@diygardeninguk ok thianks, i have one of the extractor fans in both the kitchen and bathroom but its still do`t help i even open windows, i will try clearing the roof vents in the edges as you said may help the problem.
Daniel, thanks for sharing your knowledge. Thorough and reassuring, now to go buy some of those.
Did my loft BUT having installed the vents at one level of felt, when I tried at the lower level there appeared to be a batten going the length of the loft with the felt tight to it, no way I could get the vents in, so largely felt I'd wasted the money as there's no through draught.
Bro you have just saved me a bunch of money ❤
Brilliant video thanks,i am going to check my loft more often
I fitted these lap vents several years ago and they have transformed the amount of air flow in the loft. However you still need to deal with the root cause of condensation. In my case after several hours of investigation, I found that right in the eaves of the loft it hadn’t been insulated allowing warm air into the loft space. It’s was tricky because I didn’t want to block airflow to the vents in the eaves. Anyway it cured the condensation and now I have a nice dry loft with plenty of airflow
Yes, you are 100% correct. I've also seen homes where downlights have been fitted into the ceiling and the insulation has been pulled away to prevent a fire risk, these gaps have led to warm moist air getting into the loft. Also, when it's cold outside, most ppl put the rads on and keep their doors and windows shut so the humidity in the home skyrockets and when it touches icy cold loft felt, it deposits litres of water droplets.
A lack of insulation should not change the amount of water penetrating through the plaster ceiling. Indeed, the insulation may cause it to be trapped within the insulation instead of venting.
In addition to water vapour coming up from the house it can also linger in the loft after warm, humid weather which is suddently replaced by night frosts when there's no breeze to replace the humid air in the loft.
I bought these after seeing this last year. Fitted in March. Now it’s cold again, they have made absolutely no difference.
Good vid.
Good bloke.
Cheers Dan
Excellent. Very informative and reassuring.
Great advice thanks for sharing
Thanks Daniel
Thank you for this video, you have really put my mind at ease and I'll get some of these vents.
I went into the loft today to get some Christmas presents we had bought down to wrap and there was a lot of condensation on the felt and some drips down the middle of the boards as we have had our loft boarded (properly using loftzone) I was very concerned, however my fiancé had recently had a bath and we also have badly fitted down lights in the bathroom. I will check on it and fit the vents and hopefully all will be okay. Its also incredibly cold in the UK at the moment.
I had exactly the same. I installed the vents, fitted a new loft hatch seal and made sure to crack the window open when having a bath/shower and it fixed the problem almost immediately.
I seriously wish you lived close to me as we have so many issues with our roof and loft. So far l have spent 5k and we still have problems. I am so stressed about this as its been going on since February. I live in Cambridgeshire and struggle to find a roofer who is genuine. Any ideas l would be so grateful.
If you have a vented central heating system, please ensure the feed and expansion tank (also called the header tank) which is a small cistern in the loft supplies the central heating circuit with water and accommodates the expansion of the water when it is heated by the boiler) is well covered and insulated.
We had this after a loft conversion. That old black felt is absolutely a menace as it doesn't breath, we added these vents after the fact as we still had ceilings to replace. Unfortunately this winter has made the issue come back due to the very low temperatures.
Thanks, Daniel. Very helpful..
Dad i have a wet loft .......like the one you have just shown us ..my daughter contacted her landlord and was quoted £1500 to put it right ..So i machined a load of wedges from a plastic called Stockboard. approx 150mm long and tapering from25mm to 0mm . inserted these exactly as you have ..cost £25 ....the loft is now bone dry ..didn't even get a thankyou from the landlord ,,(I'll take them out if she ever moves house )
thanks daniel , we got the condensation ,we got a few drips, so will be going to have to sort out , ,at the moment lots of various goods up there and my cloakroom distractor stopped workin 3 yrs ago and upstairs bathroom 2 yrs ago ( naughty boy) . we have black patches or spotting on ceiling just under the eves front and back rooms IS IT A LEAKY ROOF FROM POROUS OLD TILES OR IS IT something else ?
ps live in end of terrace sim to yours
Brilliant, thanks!
Really really valuable information!
Great advice, many thanks!
Got 10 plastic vents and 4 tile vents - 2 each side but still getting issues on very cold days. The soffits are asbestos board than have been capped over so no ventilation. It’s like to put more ventilation in from eaves but how would I do this if I can’t touch the asbestos?
Thank you very much. Really informative and I'm just about to order lap vents to solve my loft moisture problem (due to the current cold spell) identical to the one you describe.
Thanks! Really helpful. Silly question, but I couldn't tell a cowboy builder from the town Sheriff 😞: If I wanted to get a professional to have a look at improving my attic insulation / ventilation, are there any trade body memberships I should look for so I know they are reputable?
Your videos are amazing, I'm surprised you don't have a lot more subscribers! One question I have. Is this kind of felt lap vent enough for the entire roof, or if I'll have loft insulation put in, should I pay for that proper vent as well that goes through the roof and can be seen from outside?
hi, thanks very much for this. I am doing my own loft insulation. There is already about 100mm of loft insulation from the previous owner (they must have done it back in the early 2000s). I will top these up after inspecting them (and replace where needed). A question I have is: do all roofs have that vent on the side of the roofs like you mention at 03:16 ? I can't really see mine as there is a slope and it's hard to get underneath it with on lying on my stomach, and also the old insulation is in the way. What am I looking for? thank you
Great advice - Thanks
Great video, thanks a lot @diygardeninguk. I realized lately that my roof suffers from condensation and has no ventillation system at all. I will start by installing some of these lap vents between the underlay sheets. My roof doesn't have any vent tiles or eave tiles at all so would you recommend still getting a few of each (to cover bottom and top) installed by a professional? Just wondering if the lap vent will be enough on their own without any opening at the eaves and top of the tiles. Thanks
Brilliant video, thank you!
Great video thanks very much! I have non breathable felt on and just had 90mm eps external insulation attached to my solid walls. So disappointed with it as all it's done is contained and increased moisture into the house and now has nowhere to go except the roof. I'm going to install loads of these vents myself and then also attach a breathable superquilt foil to the roof rafters. I'll leave the last ones unstapled so can check up if the moisture is escaping clearing. Would that work out OK though? I had a roofer guy round and he suggested I pop few roof tiles off and install vents at quite a cost but going to your options first
The lap vents will work just as well as vent tiles, just cheaper and easier to install, so I would start with those. If the new external insulation has reduced the breathability of the home, then can this be improved by installing or upgrading the trickle ventilation in the home? (less moisture in the home = less getting into the loft). This should have been predicted and trickle vents specified by the insulation installer at the design stage of the works (I'm assuming that the original walls were breathable and the eps has reduced the moisture transfer rate). R.e the "breathable Superquilt", this will require an airflow behind it; between the rafters at both the top and bottom of the roof - this is usually achieved with eaves vents and a ridge vent but I can't see why the lap vents wouldn't achieve the same result. However, I would first contact the manufacturer and ask them for advice. If this were my home, I would try to get the moisture level under control via trickle vents in the home and lap vents in the loft before I spent too much on expensive insulation products. However, as I'm sure you can appreciate, I can't see what existing trickle ventilation is in place, nor do I know the humidity levels in the rooms or the materials used in the solid wall so I'm making assumptions.
@DIY Gardening That is good to hear, i can only hope it works. I didn't have these problems until the Eps was fitted. Standard solid walls, the heat was just passing through the wall before with no condensation. They drilled holes in all the double glazed windows and installed trickle vents everywhere so very breathable and letting in more cold! For some reason, the new eps measure has made the whole house twice as cold than before. None of it is making any sense. And Because of a poorly built open plan extension downstairs, the upstairs rooms are now 5 degrees acting like a reverse vacuum, pulling cold heavy air down dropping at night and warm air is accending out of the building. I do have vented soffit and fascia and the eves are clear with lots of draft coming into the loft. The roofer was very puzzled why the the felt is condensing with so much airflow. I am a total layman but assumed it's because that is the dew point and the trapped air has nowhere to go when it hits the felt. I feel the coldness dropping down can hopefully be stopped by superquilt and would also help keep the inside of the felt warmer too preventing it from condensing? Yes there will be plenty gap, 100mm behind it enabling it to breathe. With the vents there, the quilt should give adequate time for the moisture to find a way to escape, all in theory. I have no idea. But true, I need to focus and verify on getting the moisture under control to safety exit before wasting further money. I also have 500mm of fibreglass wool up there. Very confusing how the cold air is penetrating that stuff.
You are likely in the UK, maybe a former railway crossing or former farm workers cottage or similar? The solid wall structure (brick?) would have been of the age where lime mortar was used. Brick and lime mortar together are superbly breathable, but alas now shrouded and 'bagged' by the external insulation system. Often old stuff is best, for whilst cold in winter, it would also be a superbly cool refuge in the fiery heat of summer. Swings and roundabouts.
I used to live in an old xing cottage for about 6 years in Suffolk. No elec, no mains water or sewage, just a coal fire and paraffin lamps (1970s), seriously, and winters are cruel in East Anglia, but survive we did, fortifying you could say, single glazing too. It was the norm. Kind regards.
Thanks for the advice which we took but there is still some condensation up there and we put loads in. Cool air - well freezing at the mo coming in so where are we going wrong?
Try changing some of your daily habits to stop the water vapour getting in the loft in the first place. Keep bathroom door shut and window a jar when showering/bathing, especially if you do not have an extractor fan. If you have sopping wet clothes on every radiator in the house, you have to open the windows, to let the moisture out the house. Even if it's freezing outside, unfortunately. If you have a some kind of water tank in your loft, check there is a lid and it is in on securely. Check your loft hatch seal, especially if the hatch is near the bathroom door, it might need refitting/replacing
I have fitted many lap vents and still have a lot of condensation this winter puddles in fact, the problem is one side of the house gets the sun whilst the other is in the shade and its the shady side that get wet, Due cost of electric ( thanks government) i stopped using the dehumidifier but have now fired it up again, the wetness may be windblown into the roof .
Having said that you have put my mind at rest, ( littlebit)
Would this help with condensation dripping from bedroom ceiling? In winter
Epic. Thank you
Great video thank you !
Hi, some of my felt has basically rotted and fell down. Is it ok to leave it do you think?
Thanks for the video btw
Thank you for this
could you put PIR insulation under the rafters with these vents installed?
Yep although would be somewhat redundant if you’ve already got insulation on the floor of your loft. If putting PIR between the rafters I would recommend leaving at least 25mm ventilation gap between the underside of the tiles and the top of the PIR board to ensure any moisture that gets through the PIR can still be ventilated out the soffit vents and/or the lap vents, else it will condense on the top of the PIR and possibly drip back inside the loft.
Hi, thanks for the informative video. I noticed that all the manufacturers put a warning/caveat about tile up lift and driving rain. I wanted to install some of these in my 2019 home as while I don't ever see condensation in evidence yet the loft always feels damp and musty. I can't find any single source of water ingress or leaks etc. its just generally damp feeling. There is periodically white mould which I clean off with a contact spray. So I wanted to try these vents and noticed that our membrane is a Sandtoft membrane (supposedly breathable yet, it blocks all the airflow from what I can see). They have also been glued together forming a continues layer. If I install these vents low down towards the eves (which also have vents) by unsticking the sections to insert them am I opening myself to a whole world of pain? Thanks.
How will these work without getting Fresh air in?? Don't you need soffit vents to bring in fresh air?
Hi, we're in scotland where roof installation is different. Got this off screwfix buiders talk - Rafters must be covered with rigid 'sarking boards', a traditional form of timber cladding. Over this base a breather membrane underfelt is laid, held in place by counter-battens and fixed across them. This leaves a ventilated air space under the tiles'. The sarking boards in our attic (new roof done Oct 2022) are moist to touch and think it's condensation. Would these work with this type of roof.
what do i do if there isnt any vents in the eaves/soffit and if i only see the underside of the felt outside?
top info!
Thanks for the video. I topped up my loft insulation February '22 and now (December '22) by 200mm as in your loft too. I noticed a lot of condensation in the loft space to get the Xmas tree down. I have removed some of the additional insulation I added to see if that improves matters, where it had perhaps been added too close to the corners like yours. I was tempted to buy these lap vents but wanted to understand if they performed in the real world or not. I have solar panels on the roof so adding vents to the outside isn't possible.
Could you share your thoughts on how they are performing a few months on from the installation please? Many thanks again for this video
Hi Wobbly Wobbly, i have installed these in my loft and they work really well. I would recommend you put one in every other space between the joists on one side of the loft then on the other side of the loft do the same but stagger the vents so that the vents are not inline! hope that helps
@@FixitwithFowler That's fantastic, just the sort of detail I was hoping for. I'll get them fitted as soon as they arrive in the pattern you describe. Have a great Christmas and New Year
Fox it with fowler, could you describe again the pattern of vents you recommend? I understand doing each side of the roof differently,so the vents don’t face each other across the roof void,but how many vents per each run,between the rafter,top to bottom? If that makes sense
I’ve fitted a total of 18 to a roof void 10m X 3m
Also fitted soffit vents every 700 mm
Reckon that do it? even without tile vents?
Great video thanks again
Good stuff mate. Never saw those before and will definitely be buying some.
Hi can you help me I am living semi-detached building 1928
And have problems with damp in loft?? So that shall I do first please
A great product. It wont work on roofs with sarking,( for instance in Scotland). Most roofs in England have no sarking boards and just a dpm and then tile battens and tiles.
I have just checked the price on Amazon 18 Dec 22, these are now £4 each, so they have doubled in price in 4 months.
Hi mate can I ask your opinion on something? A company phoned my elderly mother just before Christmas offering a damp inspection in her loft. They came out that day and said there was damp in the timber. I've seen the photos they sent of this and the highest moisture level according to their gadget was 14.3%. That was the highest. Anyway they persuaded her to let them install a foil ligning on the inside of the roof itself and treated the timber with an anti fungal treatment. It's not even the thick foil stuff they've used, just regular stuff you can buy in Wickes. They charged my mum over £2800 for this.
Then the other week they returned again and said that the loft insulation on the floor (the usual fibre stuff) was still wet and they charged my mum another £2800 to remove all the loft insulation and treat the timber again with some form of anti fungal treatment.
The loft now has no insulation bar the foil stuff on the roof and my mum has paid nearly six grand for all this. It's a 3 bed semi detached by the way so not a huge house.
I think my mum has been badly scammed here. What do you think? Thanks.
Are you in Scotland? Call Home Energy Scotland to see if she can get help with new insulation. It's called Simple Energy Advice, in England. You should go to Trading Standards and the Citizens advice bureau about the company if you think they've misled your Mum.
I’ve just brought some of these to see if that works.
Just sent for some......will return and report on how it goes
I've thought about these vent before but the bitchumen roof felt is very brittle and tears, any advice?
Would this not just open up a gap for more moisture to get in-between making the problem worse?
They vent out moisture that enters the loft from the home below (cooking, drying clothes, breathing, bathing etc) and are similar to how you may open a bathroom window to vent out steam/condensation after a shower. The reason condensation has become such a problem in the last decade is so many homeowners have replaced drafty windows/doors with airtight double glazing and also insulated/draft-proofed their homes to the point that there's no airflow to pull out the moisture-laden air. The situation has become so problematic that in June 2022, the Building Regulations were changed and now trickle vents must be fitted to windows and doors at time of installation. This will reduce the buildup of condensation in the home so there should be less condensation and mould around windows, ceilings and in the loft. Loft lap vents are an easy and cheap way to vent out any moisture in the loft. Also worth pointing out that all new-build homes come with loft vents (usually top and bottom and permeable roof felts). The Government has published a guide to condensation and in-home ventilation but unfortunately it's very basic - www.gov.uk/government/publications/home-user-guide-template/existing-home-ventilation-guide
Can installing lap vents potentially lead to pest issues e.g wasps nest?
I had wasps nests in my attic anyway, if they want to get in they will.
I have the same type of felt. I bought the lap vents but the felt feels very tight to push the vent through. What should I do?
Wait until summer when the felt will be more flexible.
Hi Legend27, I have installed these in my loft and had the same problem. I used a paint scraper to gently prise the felt joint apart, then once you side the vent in its worth checking that you can see daylight to ensure they are working!
I think over time the layers can get stuck together. I had a few laps that seemed much tighter than the rest but I just gently but firmly wiggled the vent into place. Seemed to be fine.
I just found lots of condensation that I’ve not noticed before. (Xmas boxes were wet) It’s winter now and I cleared out the loft last year so it’s nearly empty rather than over full but maybe blocking ventilation where what is left is stored? 😬 Also I don’t have the heating on much due to cost? New bathroom? It’s on both sides so I dont think it’s due to anything being broken? If there’s any suggestion if any of these will cause an issue? Im going up to put these vents in today and hope it works. 🤞🏼
Install the vents.
Check your loft hatch seal, especially if the hatch is near the bathroom door, it might need refitting/replacing.
Keep bathroom door shut and window a jar when showering/bathing, especially if you do not have an extractor fan.
If you have a some kind of water tank in your loft, check there is a lid and it is in on securely.
If you dry wet clothes in the house, crack a window or two open to let the moisture out. (Water has to go somewhere, either up or out)
These steps will make a massive difference.
@@superspecky4eyes thank you! I added vents and checked again (when I put the Xmas tree back up there lol) and it seemed to have solved the problem. I also moved the things stored in the loft so there was more air movement. Hopefully that has helped
What type of vapour barrier Tyvek? Or something similar.....
Tyvek is a breathable membrane rather than a vapour barrier. Vapour barriers are more like plastic sheets, typically green in colour if you go through places like Screwfix/toolstation to get it.
Ty
Unfortunately, my joists are too close together and the felt is too tight to fit anything behind...
Hi! We had new fascias and soffits fitted to our 1970 build house last year……the old ones were wooden and these are upvc tongue and groove…..They have no vents! Now after years of living here and never having an issue black mould is growing in the corners of two upstairs rooms…..we’ve had several roofing companies visit and they tell us different things….ranging from insulation to new roof vents ( we havent any )….. the cheapest option was adding roof vents and that was £1000…..and ideas to save us money…we are worried as they have said different things we will choose the wrong one and waste much needed money!
This sounds very similar to our situation minus the mould issues. We have recently had our fascia and soffits done and like you the company didn't install any vents and now we have a sweaty loft. I'm going to try these vents to see if that improves things then failing that I will get some external vents fitted to the soffit boards.
If your problem started with the new soffit and fascia, then that is the way to go. Fit new soffit vents, because if no air can get in anyway then even the felt lap vents will not be of any real use. Probably your 70s wooden fascias and soffits only needed a lick of paint, and everything would have been just fine. Scaffolding and ladders were needed either way, and sure the plastic will last forever per-se, but the roof it is attached to won't without cross-flow venting, and the quality of the accommodation has been thus degraded to boot. Pvc is so often a lose/lose option.
I don't have an attic or loft. I do have a ridge vent and im trying to figure out if i can cover it with shiplap like im doing my ceiling? Or do just leave it uncovered? Which looks tacky. Please advise. Ty
The bitumen in my roof is pulled so tight, the first one I tried instantly ripped the felt. Can't fit them in anywhere. Shame cuz I bought 20 of 'em 🤣 Back to square one now...
Where do i find this product?
Via Amazon - amzn.to/3W0od9P
Hi Daniel, we have the following problem. We're in a new built house and have boarded 2/3 of the loft. The non boarded part of the loft is dry the boarded one is soaking wet. I know that the guys who have installed the boards were literally walking and sitting on the insulation and they have also cut down the boards in the attic without removing the waste which was left on the insulation. Please tell me if this is the problem (insulation) or it could still be the ventilation? We have boarded the loft in April 2022 and already in October 2022 there was lots of condensation. Now it's so bad that there's black mold. Please advice on what should we do.
Where it is boarded I imagine the eaves ventilation has been obscured.
Put a pack of 10 Manthorpe vents into my roof space about a week ago, as I had quite serious condensation when I checked about a month ago during very cold weather. Just checked today and apart from a couple of small patches, the felt is now dry looking. I only managed to put them at about halfway and three quarters of the way up the roof, as I am not good with ladders or crawling on rafters! Seems to be working, as there is definitely a flow of air through, as I can see the cobwebs moving.
I also invested in a smallish dehumidifier to place next to damp clothes and it seems to be keeping the house humidity down to just under 60%.
Hi
Air is already coming through the felt, so what is the point putting in the vents, it is just another product to sell. The problem is the overlapped insulation, which causes the condensation and damp
I don't have any felt under my slated roof.....
This nice guy had no condensation issues yet he decided to make his loft insulation worse by pulling them in 200mm and tamper with his loft ventilation. Did he just do it as a hobby me thinks
It’s common sense you need ventilation to prevent damp, condensation etc
People these days don’t have common sense 😂
Then you get office workers who look down on tradesmen thinking their dumbasses, when in reality without tradesmen the worlds fucked
I did this and installed a thermometer. Now the humidity in the roof is 99%
Ventilation reduces humidity. Having radiators on, drying clothes indoors, cooking, bathing etc or anything that produces moisture will increase humidity. Condensation in the loft will ease once the outside temperature increases and the vents will stop the loft from getting damp, musty and mouldy. During cold weather periods, I'm careful not to produce excess moisture - I don't dry clothes on rads, I open windows in my bedroom in the morning, in the bathroom after a shower and in the kitchen after cooking etc as this reduces the moisture/humidity in the home.
where you bought them for 2 pound each lol
Ariel genevieve stanley i dont know where she is she is stayin in evergreen deland pennsylvania
what happens when the kingspan goes in
On the underside of the roof? Then the loft will no longer be cold and uninsulated, it will be warm and no condensation should form - provided the Kingspan insulation is fitted correctly. Lap vents should only be used in cold, uninsulated lofts as condensation can form on the cold surfaces and this needs to be vented out.
@@diygardeningukI’d only caution, based on my personal experience, that the Kingspan should still leave a 25mm ventilation gap between the top of it and the underside of the tiles. I stupidly pushed mine flush and during particularly cold/still spells moisture would condense on the top of the kingspan and drip back into the loft. Now that I’ve pulled the PIR down an inch or so all has been fine.
If you push the bitumen felt up like that, surely you negate the felt's ability to let rain water that's been blown under tiles run freely down the centre of the rafters into gutters? The water will run either side of the plastic insert and you'll have rotten battens sooner than necessary.
Thanks for the easy explanation - great video. If there is a membrane, instead of felt, the KimaAir Inside Out vent can also be fitted from inside (apologies for the plug!) - th-cam.com/video/c1-y0NPIiN0/w-d-xo.html