Removing, Insulating and Restoring a Suspended Wooden Floor. Part 2 of 3
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- เผยแพร่เมื่อ 26 พ.ย. 2013
- In this part of the restoration we install the netting and thermafleece insulation. Once the pipes have been insulated and the insulation placed between the joists, the vapour barrier is attached before replacing and securing the boards.
Damp Proof Membrane: amzn.to/2nLUna3
Cut Clasp Nails: amzn.to/2nM9mAT
For more information and for other details on our floor restorations please visit our website and subscribe to the channel.
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I particularly love this video. some great tips. the pipe insulation trick (to cut the angles); also the netting to hold up the sheepwool insulation. great work guys. thanks for sharing this :)
I love this video and your lifting tool, thank you for sharing, I think it is great that people give you advice and you take on board what they are saying and explain your reasons I just cant believe how rude some people are and I hope it doesn't affect you guys at all, I don't see their videos on TH-cam , well done
Thanks for sharing this video series, really helpful. I think it would have been very difficult to find tradespeople to do a proper job like this.
Wow - you just inspired me to make the original 1892 t&g boards the final floor - I'll just lay a rubber anti-fatigue mat by my workbench. I'm regretting cutting up the boards to pull half the floor for wall reconstruction, but I can live with the rough look in a workshop (and most of the joints are under the workbench).
Just done this. We discovered that under our floor boards downstairs, there was absolutely no insulation and the heating system pipes had no lagging at all. We insulated in the same way that you have done in this film. thanks.
really good job on the uplift and insulation! very methodical and a smart way of doing it.
Thanks, it was one of our first jobs in the house but one that I am glad we spent time on doing well.
Great job. Thank you for your time and effort to make this video and share it with us. Greetings from Croatia.
Have you notice massive difference I'm going to do this, I love your videos and massive fan.. The timber work got me with attention to detail with the dowels..
Yeah well worth it. The insulation keeps the boards warm to touch but best of all is that the membrane cuts all drafts coming up. 😀
Brilliant videos, Thankyou
class video, class job. really useful. thank you.
Interesting debate on the membrane "issue".
I am now on second "old" house. First 1930s had a bone dry solum and good underfloor ventilation. I insulated with rock wool no vapour barrier. Design is IF accidental water were to spill on floor it could find its way through and then evaporate. You do not want solid insulation keeping floorboards wet - problems.
Current house 1890s had poor solum conditions and inadequate ventilation. Solution now is dig out solum install gravel 10mm riverbed round then a DPM then 4" concrete. Damp solum isolated and only moisture ingress now through below ground walls. Insulation is rock wool held up with garden fabric stapled to underside of joist. For dwarf wall and perimeter I installed 100mm solid insulation to allow air movement below the floor. Old houses need good air movement under the floor to prevent problems. Concreting solum is a real pain after digging out solum but it's the best way to improve on the Victorian shortcomings compounded with 1960s vandalism of blocking up fireplaces and installing double glazing which killed off air circulation in these houses.
To improve ventilation I am opening up airbricks from 5*4 to 9*5 with greater x section for flow. Will be putting video on a channel soon to show my approach. Appreciate there are several ways to skin the cat.
Like your videos Restoration Couple - good effort.
You never posted any videos
Great video! It appears the boards went back into the exact same position, therefore did you nail back into the same existing holes?
Superb video thank you, subscribed! I am about to do this in a room measuring 1.7m by 2m, but not for the purposes of insulation but rather block smells from the flat below. I live in a first floor flat in a Georgian house and the person below smokes excessively which is really affecting my flat and quality of life. Will rock wool, then a membrane and expanding foam the in the gaps work? I'll do anything at this point to block the smell. Beneath my boards is a void and then the plasterboard ceiling of the tenant's flat below. I don't understand why the cigarette smoke smell is so strong.
I learned to use a VCL layer under floor boards in Scotland as an apprentice. I don’t do it anymore in old houses though because I believe it is an unnecessary step that could exacerbate interstitial condensation. I prefer to use either a nice new board with intact tongues and grooves or a subfloor as structure and old floor board as decoration.
Yeah, I grew up in Cambuskenneth, and the Forth used to flood under the floor at high tide. I am doing floors in upstate NY now, and only use XPS or spray foam.
@simon orr that’s pretty cool. Us jocks get about eh? What took you over there and how are you finding it?
@@stevend9960 Hi! I worked in mining in Africa first, then got out as there was a war on. Went to grad school here and then worked for the UN. I noticed that Scots and Irish were in the toughest countries, unlike the English. They went to the Costa deli Sol!
Would it be advisable to leave a small gap (less than 3 mm) between each floor board to allow for expansion in case of dampness ?
Great video.
In our reception room we are looking to do something similar, unfortunately we discovered wood worms had taken his from the pine floor boards. We are looking at the different options and wanted to get your advice.
Should we replace it with reclaimed floorboards or should we use plywood as the underlayer?
Great job. About to do something similar. What is the name of the vapour barrier you used? Looks ideal.
Would you need the vapour barrier on top of joists if you was laying chipboard flooring then laminate, with the laminate underlay containing a dpm ? Would this suffice for stopping the heat meeting the cold air underneath ?
Thanks
Loving your videos, so much info and things to take for my spring renovation but I wanted to ask, why wouldnt you use screws, instead of nails to put the boards down again? Ah, I did some reading. Wood damage and shear strength!
I have a 1920s...maybe 10's bungalow which is letting is so much cold, so I need to do some works. Fun, fun, fun!
We did something similar but used batons, ply and solid insulation; celotex, well worthit room is sooo much warmer.
Is that solely down to the underfloor insulation only? I'm considering it, but not sure its worth all the effort..... ?
hiya, great videos and great motivation for all sorts DIY... Wondered why you didn't put a ply subfloor in to give it extra rigidity? With a ply subfloor would you still go with the DPM or you reckon ply has enough of a barrier function? ta
Hi Tim, did you insulate your upstairs floors. What product dit you use?
I have taken up my floor, I was going to take up joists and lay damp proof membrane on actual ground and put new joists in and then the floor , never thought of insulating... but saw you put membrain on top of joists , will damp get through the walls and will damp under effect insulation
The membrane on top is purely to stop condensation forming from warm moist air from the room. Ventilation is the key to keeping the floor void/crawl spaces dry and free from rot risk. The insulation will also remain dry and breathable from the air movement below.
Floors should be breathable too!
Is there a link for sheep's wool insulation? Much appreciated 🙏
Hi, thanks so much for your videos - they’re brilliant. I’m planning to insulate my floors in the same way you have but I also have a fireplace to contend with. I’ll be ripping out the fireplace and fitting a wood burner. Would you insulate beneath and vapour barrier up the wall behind the burner with a render finish? I wasn’t sure what impact the heat of the fire would have on the vapour barrier and conversely whether without putting a vapour barrier down the additional heat from the fire would cause a greater level of condensation. Thanks!
Render will be pretty much vapour tight so I wouldn't worry too much.
I tell you how I did it
After restumping and removing ducts and some rubbish i am left with 90x45 joists an my insulation is polysterene 120mm thick ultradense so I used the same old floor to add another 40 mm in depth underneath and made slats like in a bed for the insulation to lay on. never wil fall and stay in place stapling in place for maily not to let any part move.
Morning! I am installing acoustic insulation under my 1st floor, floor boards. Do you think I still need to to have a vapor barrier on top? Plus, so far.. I have not installed any netting, so the insulation is directly on top of the plasterboard under the joists. Which leaves a gap on top between the insulation and floorboards (the same size gap which you have from the bottom of the netting of your insulation to the bottom of your joists in this video.
Kindest Regards,
Jay
Diagram: www.soundproofingrus.com/wp-content/themes/soundproofingrus/images/acoustic-db-boards-and-rockwool.jpg
Thank you. Is it a dirt foundation or cement under suspended floorboards? I am restoring ground floor house over 100 years. Dirt foundation. Maybe pipes? All recommendations very welcome. There's a river across street and a lot of rising damp.
Hello and Greetings from the great state of Connecticut in the USA! I live in a 240 yr old colonial home with American Chestnut floors with no subfloor or any sort of insulation. So you can imagine, it gets a bit chilly in winter. Your video series is the closest thing I’ve seen to a solution to my problem. However, I have a few questions I hope you can answer. 1- Was the netting you used just that, a netting or was it woven into a fabric? 2- the lambs wool insulation looks great but I’m concerned mice will make a home with it. Have you had any problems with mice? Thanks much
Great work mate! Curious - did you consider installing subfloor? I’d like to put radiant heating in my 100 yr old house. Adding it to the bottom of the floorboards feels like a shortcut.
I kind of like the idea of the membrane, only issue is that if you spill water and it gets through the varnish, it is a bit stuck
Water has a habit of evaporating.
Hi there, between removing and relaying the boards, what remedial work did you do on the joists?
Just checked for any defects, damp, wood beetle, because we have decent ventilation under there they were 99% ok so should be good for the next 100 years!
Is it ok to put the floor boards over that netting that supports the insulation?
Would the membrane behind the skirting become a bridge for moisture? We have a hung floor in a Victorian part of the house. The walls are brick with no cavities.. I thought it was all about a bridging gap?
I’m thinking about doing the same thing in my house. If you were to do it again would you use the same method or use PIR insulation. Would love to know your thoughts!
Hey Chris, I was about to ask the same question, lol. Hopefully, Tim will see your comment and reply.
If possible, you should try and leave cables on top of the insulation. It's not really possible to have them on top of the DPM unless you use rigid foam in which case the DPM is essentially part of the insulation. Anyway, at some point you will need to service wiring etc. You don't need to tear down the whole house to do that. Even if you have to cut the DPM to get to the cables, you can tape it back up quite easily.
the cables should be below the insulation (not insulated) otherwise they may overheat. If you put cables in the insulation then you need to use much thicker over-specced cables
Hi, great video! It appears the boards went back into the exact same position, therefore did you nail back into the same existing holes?
Good question. I have just checked and for most I nailed beside the old holes. We then filled all the holes with a colour matched filler.
Great video! Going to follow all the steps but I'm been told that the damp proof membrane should be underneath the insulation because it will stop moisture reaching it? Could you explain it to me please
Hi Michael, It is important to place a vapour barrier on the warm side of any insulation, in floors that is on top. This prevents warm moist air from inside the home reaching the insulation/joists and condensing. This is the 'dew point' and condensation within the insulation is a bad thing. Ideally you do not want anything below it apart from netting, this means that the insulation can breathe and providing you have good air flow underneath you should have no problems. Any non breathable membrane below insulation is asking for trouble in my books as you can end up trapping moisture in rather than keeping it out.
Did mine last year. Noticed no difference at all except I have more condensation and mould now.
Is a vapour-proof membrane over the floor a good idea? As it's non-breathable, I would worry that it may encourage condensation.
Otherwise, great vid. Thank you. :-)
The opposite. It prevents moisture reaching the cold space below where if would condense.
Hey! Great video! We're currently looking into doing this ourselves but we were wondering if there is a difference between the way you did it and using Celotex 100mm insulation boards? And what are the pro's and cons of doing it your way?
Providing they are nice and snug between joists and on battens to stop them dropping then fine. We just chose our route as it was a natural product and slightly cheaper. I have used celotex for the roof and other areas so just personal preference. 100mm PIR would be slightly better u value anyway.
The Restoration Couple thanks for the speedy reply! Ill be looking tomorrow to see what the situation is. Would I be right in thinking that using your method would be easier than installing batons to sit on?
Hi, thanks for the great videos! I'm wanting to do this to my livingroom. Can this be done without removing the skirting, ie cutting the membrane to size and using builders caulk for the final gaps?
Ideally you need to get them off, you will probably find that your floor boards go under them anyway. TRC
Thanks for the reply. I will be cutting the boards, as it's carpeted. I think I will use butyl tape to create the seal.
Hi thank you for posting, what is the purpose of insulating this floor? Thermal? Acoustic? Both?
David Gordon thermal really as they were cold draughty boards before.
Great work. Galvanised mesh could of been good idea to cover the air vent 6.00 to prevent rats entering the under floor area from the cavity walls. Under your floor would provide a ideal home for rats
Rats can't get through air bricks
Hi, sorry to mither but can you please confirm if it was Thermafleece Ecoroll or knauf Earthwool you used in this room? (Thermafleece is in your description) Looking at the video near the beginning it looks like a roll of knauf sat on the joists? ...I'm after getting the same as you praise its thermal properties when someone asked for an update on your video.
Sincere apologies if I'm incorrect. Just been let down with an insulation delivery and my daughters and I are freezing after taking our floorboards up, need to get done asap. Many thanks.
In these rooms we used the sheepswool rolls. To be honest as much as I liked the product, I would imagine most soft insulations will give you a similar thermal performance so whether you use sheepswool, mineral wool or recycled plastic wool they will all make a great improvement.
Hi mate. What material did you use for insulation and where did you get it from?
I use similar polyester R2.5 but I am in Melbourne Australia
Would have liked to see how you put the netting down.
Hi, great video. Is it possible to lever or clamp the boards together before nailing to eliminate the gaps. Or sand the bow out of the timber? The nails look nice but did you use a nail gun or by hand? Cheers Max
Hi Max, You can get them as tight as you like however if they are anything like ours there well still be some shrinkage, especially if insulating below. Prior to this there would have been slightly damp air below so they will always dry out slightly after being relaid. We left ours with some character however you can sand them right back to be dead flat. We did this in part 3 of the videos. Tim
Is that vapour layer fire rated/safe? Looks like its a simple black foil? I just bought similar but i am started to be concerned about using it. The Rockwool/Earthwool is pretty safe (literally not doing anything even exposed to open fire) but putting this over might not a good idea. The sockets or electrical wiring definitely should not be in contact with this.
Dear
The Restoration Couple,
When you nailed the boards again did they not tear the DPM membrane (where the nails penetrated the membrane) thus letting moisture up ? I have heard many people go on about it and keen to know how your floor stood up to moisture after 5 years. Thanks
Membrane is not there to stop moisture coming up. It’s to stop it going down from the warm house air. Nails or screws through a vapour barrier essentially self seal and not a worry issue. Would be different if yo were aiming for airtight passive spec. I’ve been under the floors on several occasions and no issues. With it being a vented floor there is very little chance of an issue anyway.
Great video, thank you. I've seen some of your more recent videos where you put a breathable membrane down then the insulation. Then a dpm. What materials did you use as I'm planning on doing this. 🤔 thank you.
Membrane or mesh is fine, both breathable and good for air flow. Depends on the build up whether you use a vapour barrier above or not. Definitely worth using something to reduce draughty especially if old square boards.
Where can I get one of the twin bladed floorboard lifters?
toolstation
I insulated the floor this way for a change of use project in 2010. No issues with it. Would have been even better to use pir board laid on to battens and then taped.
Hi Tim, We're looking at a similar job. We've got 3" x 4" joists so 100mm depth. If we go to 100mm depth of roll insulation we don't get a sufficient U value. I queried with the council and they think I should be using PIR slabs which would achieve the U value. I'm arguing this isn't practical so we must do the best we can per the regs. The gap between the joists is 340mm which is non-standard which will lead to quite a lot of waste. Insulation on a roll is going to be much more forgiving. Just wondered if you got building control involved on your project although it looks as if you had a bit more dpth to play with.
Rob Ford The PIR slabs have superior thermal efficiency than a wool based insulation hence the higher u value. If you buy big PIR boards you can cut them to size as you go. On a later video, Tim provides a link where you can buy PIR ‘seconds’ making it much cheaper.
so if condensation forms, it's going to be under the wooden floor...am i right? or it won't be a problem because heat rises naturally
+arjuna207 condensation only occurs where it is cold enough to do so. The most likely place would be within insulation which would be bad. The membrane stops the moist air ever getting that far.
Wonderful videos as always.
Quick question - if I use earth wool, should I still use a membrane? Best regards.
I always try and use a membrane on the warm side of any insulation to cut down on risk of condensation. If you are using a breathable insulation then you could do without but still chance of drafts with old boards like these.
+The Restoration Couple cheers bud. Have a good day.
Hi, I know it may be too late to comment, but how big was the room and how long did it take you to remove the floorboards, lay down the insulation and replace the floorboards?
4x5m. I would say 2 full days plus finishing/varnish.
If your plan was to finish by laying engineered floorboards, would you replace the existing floorboards onto the joists then cover with a thin layer of plywood (to create an inch and a quarter subfloor), or just cover the joists with an inch and a quarter of plywood before putting down the engineered floorboards (throwing out the original pine floorboards)?
I would likely replace with 22mm flooring or ply and then use the old boards for something else, or sell if decent. That’s what we did in one room which we used flooring in.
@@TheRestorationCouple thanks for the advice. Yeah, it seems like a waste to chuck them out, be good if they were sold on to be used again.
Hi there. We have just purchased our house and found woodworm. We are removing all the floorboards and having the joists treated then insulating between the beams. we intend to put down chipboard flooring instead of wood planks. Do you recommend a damp proof membrane still and will this effect the breathability at all?
If using tongue and groove chipboard I would think that when glued they form the necessary vapour barrier. Although for the cost of a few sheets of polythene it would be a few minutes well spent to sheet over first, the last thing you want is warm air from the house condensing under there. Air flow under the floor will allow wood and insulation to breathe, you do not want the floor to be breathable from above due to the risk of condensation. Hope that helps.
The Restoration Couple thanks for the quick reply. Will be using the pipe insualting tip as well. We just hope none of the beams are to badly damaged further along the room from the woodworm but it appears to only be in the one corner, but you can never tell till you expose all the beams.
Where is the best place to find building regulations?
Hi I'm getting floorboards laid on Monday. Can you please advise what netting you used, where you got it from and where you got your sheeps wool from too please? Thank you
Hi Karen, We used a black plastic mesh from the garden centre. It was the stuff used over ponds and tends to be a little stronger and easier to work with than the pea/bean netting. The insulation we used was Thermafleece ecoroll and it was amazing stuff to work with, (ideally use 150mm to meet correct U Values.) Not itchy, holds its shape and soon gains its thickness after unrolling. Let me know if you need anything else, good luck!
TheRestorationCouple Thank you for getting back to me, I have seen thermafleece on line, it looks good. My floor is being worked on right now. I'm torn about the insulation: The chap who's doing it is reticent to put insulation down due to potential issues around condensation and floor/joist rot. I see mention of that in some reports online. He reckons the flooring; solid oak and and reasonable thickness, is enough in itself. Do you have any thoughts on that?
I may as well have my two penneth worth. I've been considering options and I think that I would use the insulating silver foil type bubble wrap. I can't see how effective the DPM would be as a radiant barrier. Maybe someone could chime in. But sheep's wool insulation is a good move. It irritates me how it's almost considered a worthless by-product when there's so much work and money which goes into producing non-eco friendly PIR. Unlike sheep's wool this won't absorbe moisture and then let it go when conditions change.
How much did you pay for that house? Appreciate it if you would devulge thay info. Calum. Scotland. Considering buying a cottage requiring a lot of work.
Did you not remove the rubbish underneath the floor ?
The only thing left under there was some lime dust/plaster which came off the wall, but no way near enough to reduce airflow.
only ducting may affect air flow otherwise not if there is enough flloorspace
Massive mistake I made when restoring my Regency house was not re-using the original floorboards. They were 18" wide oak boards from 1810 and the house has 20 rooms so there were a lot! Dont even ask me why but the builders burnt them.
It would have been better to use PIR type solid insulation, as the cold, moist air from the cellar and wall vents will pass thru the fleece degrading its insulation value. Also, PIR would act as vapour barrier without need for separate membrane. And, would make it easier to access the plumbing for any future alterations or repairs.
Thanks for your comment. PIR would have a better U value at the depth however we prefer to use natural materials where possible and the cost saving was also a benefit. Sheeps wool thermal properties are not effected by moisture to the same extent as mineral wool so that was another reason we went for it. PIR would only work as VB if taped right across the top of joists I guess. Providing the sub floor space is is not damp the insulation type is less important, I would put more emphasis on fitting it correctly and getting the VB correct. TRC
TheRestorationCouple I appreciate your reasoning, but subfloors and especially untanked cellars are inherently damp, with the cold air being unable to hold much water vapour before it condenses out. As older properties tend to have poorly designed subfloor ventilation to carry away excess water vapour, there is a good likelihood of interstitial condensation within non-solid insulation, much degrading its insulation value. Anyway, with those limitations, you look to have done a thorough job.
PIR is perhaps more suitable for new floors rather than old floors
The Damp Proof Membrane is being compromised by being punctured by staples and floorboard nails????
Its the same with any VCL, I guess it's just an accepted neccessity. Besides the nails pretty self seal to a certain extent.
Hi. New follower of all your videos which I find most informative and enjoyable. I do have a question. I live in South West Scotland at 1400 feet in a 17th century stone built cottage. I am currently in a confused state regarding my new floor structure. I have removed old timber flooor that sat on ground and dug down to initially install an insulated concrete slab. Further research revealed this was a bad idea as any moisture under DPM would be forced to the outside and wick into walls. So I decided to build some sleeper walls and install an insulated timber floor using sheepswool as the insulation. However I have been told I need a DPM on top of the solum to keep the damp at bay from the timber floor. I have intoduced air vents through the wall and the solum is generally pretty dry the damp area being to the front - the rear sits on rock! Would your method with the DPM below the floor boards be suitable in my situation? The underfloor depth is vey shallow unlike your own home.
I would be greateful for your or anyone elses thoughts!
The membrane under floor boards is a vapour barrier, I just happened to have some dpm spare. If there is enough air flow under floor then bare earth is not really an issue. Dpm is effectively tanking like you say and can force moisture to the walls. I would say that providing your sleeper wall has a dpc then all should be fine. Perhaps covering the majority of the ground but not all the way to the walls may be an option.
@@TheRestorationCouple Thank you for such a quick response. I am waiting to hear if Limecrete Direct would consider coming up with a truck to mix some limecrete which I consider to be the optimum solution but cost may be prohibitive!!
one question, after all that insulation why do you need to lay that damp proof membrane? Great Video BTW..
The vapour membrane serves a couple of purposes. Firstly it acts as an airtight membrane which stops all unwanted drafts coming up through any gaps between boards. Secondly and most importantly it is there to stop condensation on the insulation. As with all most forms of insulation it is best practice to create a vapour check barrier on the warm side of the insulation. This stops the warm moist air in the room condensing on or within the insulation, which causes mould, fungus and rot. I am sure there are arguments for and against this method, however after doing lost of research we chose to use it, (cutting out the drafts has made a huge improvement on the comfort of the room.)
@@TheRestorationCouple Doesn't nailing the boards through the membrane jeopardise it's moisture barrier properties? I'm thinking to use a membrane for my project but until now had been thinking to put it underneath the insulation rather than on top. Now I'm not sure!
Great video, thanks. I plan on following this in my house. I have two questions, if you had time to answer it would be great. Do you have a vent in the room as I am worried about condesation (plan on insulating walls and attic space above room also)?
Am I missing somthing or are you penetrating your DPM when nailing down the floor and creating possible condensation points or is this not an issue?
Cheers
+Aaron Mac Raighne A vent would be needed if you were to be aiming for air tightness, that could be trickle vents or similar. In our situation we have an old house and have quite enough drafts still! Fixing through the vapour control layer was unavoidable and is a minimal risk. By the time the boards are tight down and oiled there isn't much room for air to get anywhere near.
Why not use new boards? Save on cost?
what sized joists are they? 175mm by 75mm (7 by 3 inch)
Somewhere around that, yes. They varied slightly room to room.
The Restoration Couple
I am thinking of replacing the entire first floor ceiling in one of the rooms in my house. As the above floor is very sloped due to the joists partly failing. When replacing joists would you use joist hangers to support the joists on either end (connecting to the supporting walls) or do they need to be pushed into the walls?
Would depend on a survey/engineers report I guess. You could use hangers on a timber fixed to the wall which would keep everyting above ceiling level. Cutting into walls is not idea especially if not a full renovation. Or you can sister the old joists by bolting new ones beside, which is how we did a couple where needed.
Goodness sake screw that mitre box down,lot easier
Great video. I’m going to be doing the same in the next month, so this has some useful tips.
Does the vapour membrane affect breathability, and allow moisture to flow from the void up and room back down? Worried about condensation build up under the floor.
Hello Daniel. This is my concern too. Sorry, I don't have an answer but I'm guessing the vapour barrier stops the warm air going down into the cold void and turning to condensation. I would hope my air bricks create enough air glow to keep enough ventilation flowing to stop condensing in the void. I'll be tackling this in March too. Any thoughts mate?
@@jimbob9556 Hi Jimbob,
I've decided to put in an airtight breathable (not sure how those two go together :/) membrane for the top layer - I read a good article on Ecological Building Systems website on insulating suspended wooden floors. Their pricing isn't too bad either. How did you get on?
What measure should the depth have
+Claudia Marlene Gaytan Alfaro As deep as possible really. Ideally the full depth of the joist which is usually around 150mm or 6in. Hope that helps.
Thank you😊
0:32 those remind me of pool noodles!
Great job and great vid, congratulations on taking on such a big job! However I have a question. A friend of mine insulated his summerhouse floor (under the floor was just bone-dry sand, some 20-30cm of room for air flow and 15cm joists) pretty much the same except for the vapour barrier. He also filled the whole depth of the joist with glass wool if I'm not mistaken (and covered the wool with the brown industrial paper so that the glassy fibers wouldn't fly everywhere). Anyway the problem was that because he didn't leave any room for air movement above the wool, his floor started to rot because of moistness and thats why he had to redo the entire thing. So my question is- if you have vapour barrier then you don't need air room between layer of insulation and actual floor? I'm planning to insulate my floor as well (same setting as my friend) and instead of net I was going to attach little panel strips onto the bottom of the joists to hold a lightweight floor onto which I lay the insulation. Then also the industrial paper layer and 5cm of air space. Problem is that we sometimes have ducks and suchlike living under the house and they (or mice) might start to tear the insulation out. Or bugs go to live in it. You don't have that kind of fears with your sheeps wool or doesn't it somehow attract rodents and bugs? Because they could easily tear the wool out through the net.
Anyway, I gathered here more than one question, sorry! Great job of actually redoing I presume the whole house/apartment! Keep up the great work!
+Alias KaSiin Thanks for the comment. The most important thing if using any soft insulation, mineral wool, glass wool, etc is to make sure it is breathable below. i.e netting, mesh or breather membrane. The vapor barrier on the warm side of the insulation prevents what happened to your friends which is condensation forming below boards. I would suggest using wire mesh to sit the insulation on if you have creatures below your floor, or even better try and stop them getting in there. It is best to not have a gap above the insulation as this will not reduce the effectiveness and also allow unwanted cold air movement under the boards. Hope that helps.
+The Restoration Couple Thanks for replying! Using mesh is a really good idea, thanks, I'll have to look into it. Also I think cutting the airflow completely under the house might not be such a good idea but I'll have to look into that too (it's a 55y old summerhouse built in a very shady time and I don't know what effects sudden lack of air movement would have). But if I put vapour barrier right under the floorboards - ok, the boards will be fine but wouldn't the insulation take in the condensation? So to let it dry again I have to keep the bottom breathable? So it's kinda getting wet-drying all the time? Doesn't sound too good (but then again I'm new to all this). Btw the air between insulation and floor wouldn't actually move, I said that wrong earlier, sorry, if it moved it would make insulating very pointless. The air just is there, because the ends of the joists are closed. Like in old buildings between stories - 10cm of sand and 20cm of air to insulate and hold noises back.
I'm sorry if my questions are stupid, I'm just trying to think logically based of what I've seen-heard, but that's apparently not so clever of me. But thanks again!
+Alias KaSiin You do want air movement in teh void as that will keep everything dry. Condensation can only occur when the warm air from the room hits the cooler insulation, this is why a vapor barrier is always installed on the warm side of any insulation. Whether walls, floors or roofs. You do want to avoid any gap between boards and insulation as although it may be sealed to the external air you will still have air movement from the heat above and although it sounds minor it will compromise the performance of the insulation. Th insulation should not get wet below providing it is not in contact with actual moisture, this is why the air flow beneath is vital.
+The Restoration Couple ...thank you very much for taking the time and clearing this up for me. I was being me and didn't think through why and where condensation would be and all the time I was thinking something fundamentally incorrect. Btw although I've always known vapour barrier is necessary it's been years that I've thought it was to keep the moistness of outside out, instead of keeping insulation dry from the temperature difference=condensation. Yeah... Anyway, thank you very much for answering and good luck with everything you're doing!
should have used floor brads cut nails split the board or come loose
They worked well for the 120 years before hand so was in no hurry to change. 4 years on and all good.
the nails you pulled out were floor brads not cut clasp
Membrane goes in top of insulation would thought it be underneath stop moisture damp coming up through floor
Nope. It’s a vapour barrier to stop warm air condensing. Anything under will have air flow.
@@TheRestorationCouple ok I do the same
Kawasaki zx10
Dupont - Tyvek recommend to put the membrane BENEATH the insulation (over, under style on the joists). See www.dupont.co.uk/products-and-services/construction-materials/tyvek-building-envelope/uses-and-applications/suspended-timber-floor-construction.html for a handy diagram. Is this because theirs is breathable and your DPM isn't? I think I am going to put the DPM beneath all of that - resting on aggregate and sand blinding.
+James Tyas There is no benefit as far as I am aware of using a breather membrane instead of mesh or netting other than perhaps to cut down the effect that a strong sub floor draft could have on the insulation performance. It certainly doesn't make it any more breathable, so providing the wool is not touching the ground and it is well vented, netting/mesh is fine. The DPM or vapour barrier over the top is a must to comply with regs anyway and is inline with all insulation installations where it is important to have a barrier on the warm side, i.e above the insulation. Air tightness is much easier to obtain if laying a membrane over the top of joists and sealing to wall behind skirting.
+The Restoration Couple Thanks, but I can't find where the DPM should be installed on TOP of the insulation (I'm definitely not a builder so maybe it's just common knowledge). Building regs Page 26 shows a DPC beneath insulation, but no DPM. www.gov.uk/government/uploads/system/uploads/attachment_data/file/431943/BR_PDF_AD_C_2013.pdf.
Another diagram great-home.co.uk/cms/mydata/uploads/2014/08/Batt-or-Quilt-Insulation-Applied-From-Underneath-Floor.jpg with a vapour membrane underneath. If I follow my first diagram, the membrane will still be on top of joists and sealed behind skirting, but the difference will be the insulation on top of the membrane instead of beneath it.
+James Tyas I think if you were pouring concrete on top - then the DPM on top would be a good idea.
I think you are confused with the fact we used DPM, this was just because we had some spare, it acts as our VCL. What you are trying to achieve is a vapour barrier or VCL between the warm humid air, i.e room and the cooler insulation. Failure to do that would risk condensation forming with the insulation, (interstitial condensation) which can lead to mould, etc and degrade the performance of the insulation. If you search for Vapour Barrier with insulation you will get the idea. Hope that helps.
+James Tyas Think I've understood my confusion. The one I'm looking at is "breathable" i.e. not a vapour barrier. So it's fine to go under insulation. Sorry for my misunderstanding!
concrete repair
The under floor is where the builders dump the rubble. Typically U.K. builders work.
There is no need for plastic "vapour" stuff on top. That plastic cover will do more damage in future. Show me that place after 10years when mushrooms is growing under plastic and don't call it restoration.
You needed a mitre to cut insulation foam? 😂
Wrong on so many levels
Constructive... Care to add why?
Will that installation have been mouse-proof?