How To Insulate A Concrete Floor
Insulating Concrete Floors
If you live in a cold climate then you’re no stranger to cold concrete floors in the winter. If you’re planning on finishing a basement or portion of your home that has a concrete floor then it may be a good idea to insulate it before installing basement flooring. Concrete floors are cold and full of moisture that can be a long term maintenance problem.
Methods To Insulate A Concrete Floor
There are numerous methods for insulating concrete floors and slabs. The method that you chose really depends on cost and available headroom. If you’re finishing a basement most building codes require a minimum finished head room of 7′-6″. So any choice in the insulated sub-floor must account for that minimum height including the finished ceiling construction. The following are two methods that we’ve used in the past with great success.
Insulated Sub-Floor Panels
There are numerous products being sold today that are typically a combination of rigid foam insulation and some type of sub-floor material like OSB. There are quite a few of them on the market including Barricade Subfloor Tiles. The subfloor tiles are really great for folks with little DIY experience and clearance issues as they provide one of the thinnest insulated options.
Insulated Sub-Floor
If you’ve got adequate headroom and few interferences then this is the method that we like best. This method works great if you don’t have many doors and you can deal with the higher sub-floor at the stairs. The method is quite simple consisting of a layer of foam insulation, sleepers and a plywood sub-floor (see diagram above).
- First you need to be sure the floor is clean. Be sure to fix any problems in the concrete floor such as cracks, spalls and water problems.
- Install a layer of rigid foam board insulation such as Styrofoam Tongue and Groove or Styrofoam Brand Highload 40 (depending on the loads you have the first one provides 25 psi and the second one provides 40 psi). We recommend at least 1 inch of foam board. Use a good quality foam board adhesive to adhere the foam to the concrete. If you’re interested in learning more about foam board insulating properties then check out our article on R Values Of Foam Board Insulation.
- Seal all the seams of the foam board insulation. We recommend you tape the seams with Tyvek (or similar) tape. You can seal along the walls with spray foam from a can (Great Stuff or similar).
- Install pressure treated sleepers. We recommend using 3/4″ thick pressure treated decking. Use foam board adhesive along the bottom of the sleepers and also attach the sleepers to the concrete using masonry nails or a powder actuated nailer.
- Install a layer of 3/4 inch tongue and groove AdvanTech (or other sub-floor material). We recommend you screw the sub-floor to the sleepers using stainless steel screws and sub-floor adhesive as well. We really recommend you consider using AdvanTech because of it’s excellent properties in damp environments.
- Finally install your finish flooring. You can install any type of flooring at this point because of the sturdy sub-floor.
Final Thoughts On Insulating A Concrete Floor
The only issue to watch out for in this situation is the height. You’ll most likely end up with 1 inch of foam board, 3/4 of an inch sleepers and 3/4 of an inch for the sub-floor for a total of 2-1/2 inches. This will most likely require doors to be lifted and stairs to be reconfigured. However, you’ll have a very warm comfortable floor and a whole lot less moisture in your basement.
Want To Hire A Professional?
If you’re feeling a bit overwhelmed by a full basement remodel then you may want to consider hiring a contractor. A good place to start is using industry proven contractor referral companies. Company like ServiceMagic offer a great referral service. Just follow the next link:
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Todd,
Great articles!
Couple questions for you as i’m thinking of laying carpet in my basement (there’s existing tile) but want an insulated floor:
1) I assume you recommend removing the tile first?
2) What is the downside of using 1/2″ or 3/4″ XPS instead of 1″? Any water vapor issues in that case?
3) Are the PT sleepers truly needed? Couldn’t I just tapcon/powder nail OSB or Plywood into the concrete directly through the XPS? Or are there concerns with water vapor having direct contact with the subfloor in that case?
4) Could I use 1/2″ OSB instead of a 3/4″ subfloor? Any weight concerns….not putting a pool table down there…heaviest thing would be an elliptical.
Just a little concerned with height (will need to cut bi-fold doors down), but still want to get decent insulation to have a warm floor.
Thanks for any feedback!
@ Mike – Thanks for the compliments.
1. If you’re worried about height than removing the tile will help. I’m not sure it’s absolutely necessary to remove it.
2. The only downside is less insulation value and less protection from moisture. I think you might consider a layer of poly under the foam if you go thinner.
3. The Sleepers are not necessarily needed. We’ve actually done it both ways. When you use sleepers it seems to work better connecting them to the floor then screwing the plywood down.
4. 1/2″ will work if you don’t have sleepers.
Hope this helps.
Todd, I enjoyed your article on insulating basement walls. In fact, I began my basement bathroom project, and will use your methods in addressing the concrete walls around the perimeter of the basement. Should be more than enough to handle Iowa’s winters.
I don’t quite understand how foam board has a low enough compression factor that will support furniture, etc. So am I to assume the subfloor above the foam board will take care of spreading the load across the foamboard? And any thoughts otther than price considerations for using composite decking material as sleepers?
Thank again.
@ Joe – Thanks for your compliment.
Foam board (blue board, pink board) actually have a fairly high compressive strength when they are sandwiched between two products such as the concrete below and plywood above. We’ve done this method several times and it works very well. Hadn’t really given much thought to using composite decking. I suppose that would work out pretty well aside from the price. Good luck!
Todd, thanks for the great website and information. My question is similar to the one you addressed here. I was planning on using 1″ T & G Pink Board on my basement floor and then putting 3/4″ T & G OSB on top of it and then using tapcons to screw it all directly into the concrete. I was then going to use 1 1/2″ foam board on the concrete walls and build my 2 x 4 walls with batt insulation inside the foam board on the walls and on top of the T & G OSB. However, my father in law is questioning whether the foam board on the floor can withstand the weight of the walls and OSB on top of it without getting crushed or being unstable. There will be a bedroom, family room and bathroom in the basement with typical items for these rooms (bed, dresser, couch, televsion, tub, toilet, vanity, ect) but nothing with excessive weight (pool table, ect). Are my father in laws concerns valid or will this set up be able to handle the weight? He advised using a joist system with treated lumber on the floor with the Pink board insulation between the joists.
Chris – This system is used all the time. If you look at the rated pressure for foam board insulation and you compare to code floor loading it works fine. In some cases with extra loading (pool table for example) you can purchase the stronger version but for typical room it’s not necessary. I’d do it in my own home.
Good luck.
Todd,since I do have an issue with height,could i use 1/2 inch foam & put a laminate floor on top,water is not a problem.Thanks for the help.
@ MikeR – What would actually hold down the foam? I’m just not sure it would be a very good system without some mechanism holding everything in place.
Todd,
Have some follow up questions for you :)
In looking at the XPS panels available to me at local stores, I saw Owens Corning Foamular 150 and 250 (high density). Noticed that the only difference is the compressive resistance of the 150 is 15psi and the 250 is 25psi. I don’t think they carry the 250 in 1″ size (or at least not in stock….however they do have 3/4″ 250 in stock). Which type do you guys use? Do you think the 150 is sufficient? Like another commenter, I assume the plywood/OSB distributes the load over the panel.
Also, if I didn’t use sleepers, and didn’t use AdvanTech, in general do you recommend plywood or OSB? I’ve seen 3/4″ T&G OSB be recommended…also have seen 3/4″ T&G Sturdi-floor plywood for ~$17. I had wanted to use 1/2″ to save height and 1/2″ square edge OSB panels are extremely cheap, but aren’t T&G. In such a setup is T&G a necessity? I assume it would cut down on the number of Tapcons needed?
Finally, if I leave my tile down and put the XPS panels over top, do you think there are any issues with the small air gaps caused by the grout lines? I had read the XPS should be tight against the wall/floor, but also have seen other products that market an air gap as a benefit…
Any recommendations either way? As you can see I analyze everything for better or worse.
Thanks again!
Mike
@ Mike – I don’t think there’s much difference between the 150 and 250 for your application. I do think you should stick to T&G as it really stiffens the floor. I also think you really should have 3/4 inch plywood over foam board. I also don’t think the gaps along the grout lines are a big issue.
I have a question regarding insulating a poured slab cellar floor with Barricade. According to instructions, an expansion space should be left around outside edges, but doesn’t leaving this gap create a non vapor barrier? I thought that in order to prevent moisture from the meeting of cold and warm air, you need to have any gaps sealed. I plan on using 1 1/2″ rigid foam panels on the walls before framing, but still am up in the air as to how to insulate the cellar floor. Height clearance is an issue, and I would like to be able to put down carpet. I live in the Western New York area where our winters are cold.
@ Betty – The floor guys don’t care much about the wall issues! Obviously there is no perfect solution. I would install the Barricade system first, leave the gap at the concrete. Then bring the 1-1/2″ foam down on top of the barricade.
Todd — great site. I am redoing my basement, ripping out hte old wall frames and fiberglass batts. There is an existing slab floor. Following your recommended methods for insulating floors and walls, should I insulate and put in the walls first, or the subfloor first? Also, did you see the article in Fine Homebuilding September 2009 about subflooring — any comments? Finally, if the basement will be heated and I use a suspended ceiling, do you think I need to install fiberglass insulation between the main floor joists? Thanks so much, Mike
@ Mike – Thanks for the compliment. I would insulate the floor first if you have the luxury to do so. I did not see the article, can you share the basic information and what your question is? No need to insulate the ceiling above unless you’re worried about getting too much heat above.
Todd — Scanned in teh FH article, but see no way to attach it to the comments. Essentially, the author recommends that when finishing a basement, adhere to the following method for the floor:
1. Install a class-I vapor retarder, specifically a 10-mil to 15-mil polyethelene sheet, taping all overlaps.
2. Install a floating subfloor using two layers of 1/2 -nch plywood. Glue or nail the second layer to the first layer, but do not penetrate the vapor barrier.
3. Use high-quality engineered wood flooring to finish.
Following up on my initial “wall or floor first” question, would the wall framing go right on top of the subfloor?
Thanks again,
Mike
Mike – You are correct, place the wall on top of the sub-floor.
How would you address sloping floors using this subfloor method? In my basement, the concrete floor slopes towards the outer walls and then towards a drain. Would shimming betwee the sleepers and the subfloor be an option, or might this create uneven load distribution on the XPS? Would something like Dricore panels be better in this situation (aside from cost and height differences)?
@ Jeffrey – This method could still work if you can manage to cut good tapered sleepers (this might be really hard to do). Does it slope much?
Hey Todd-
Thanks for the reply. Unfortunately I think it’s going to be too much for tapered shims, especially since there is a ridge more or less in the middle. The house is almost 100 years old, and it looks like the floor is designed to channel water in either direction away from the middle. Between that and the relatively low ceilings to begin with, I think I might be stuck with one of the dimpled plastic membranes and carpet on top of that. I’m not crazy about putting carpet in the basement, but I’m not confident that I can get the floor level/flat enough for tile or laminate while leaving suitable headroom.
Any suggestions?
@ Jeffrey – Short of tearing up the slab I don’t really have any ideas. Are you sure that you’ve got no water problems? Be darn sure before you install carpet.
How many tapcon screws would you recommend to hold down a 3/4″ subfloor over 1″ XPS foam?
@ Jody – It really depends on how flat the floor sits. First off I would recommend using 3/4″ tongue and groove AdvanTech sheathing. It will likely require 4 to 6 screws per sheet.
Follow up question,
I am using 1 inch foam with 23/32 T&G advantec board for my subfloor.
You recommended using 4-6 screws per Advantec board. Since it is a T&G, this means that screws need to put pn the edges or you need to put tapcons all around each board.
Please advise.
Thanks,
Tariq
Tariq – The number of screws really depends on how flat the floor sits. There’s no structural reason to use them. It’s really just a way of keeping the floor nice and tight to the concrete. You’ll need to adjust accordingly.
i am using 3/4 tongue and groove plywood (not advantech). at this point the wood seems pretty flat :)
I will try to use 6 per sheet.
Thank you.
one other question, i have a plumbing clean out access in the floor. What do you usually do with the foam and sunfloor in that area? i would like to put carpet or wood laminate flooring inthe room, but i know i will need to have access to the clean out.
@ Jody – If you go to a plumbing parts vendor you can ask them for a brass floor cleanout cover. They attach to the floor pipe and work with your finish flooring.
So here is something I have been thinking about. If I insulate the floor in my basement, I think I have two problems. The first, which may be a non-issue but to add insulboard, then sleeper, then flooring will case the last step of the stairs to be a weird height. Secondly, I am concerned about the clearance to the ceiling because I would like to install a hanging ceiling (want to be able to get to the plumbing and wiring.
What are your thoughts?
FredW
Disregard this comment. I did not read throughly.
Todd,
Great information. Can you comment on the following?
Background #1: I have a 2 year old home. The basement so far is quite dry (sandy soil and good foundation drainage). We lived there before we rebuilt the house and never had any water problems and no smell/mold with carpet over slab.
Background #2: I am looking for warmth, and I don’t want moisture issues to arise after we condition the space.
Background #3: We do plan to put a pool table in the basement.
I have been planning on putting down Delta-FL, 3/4 OSB (or other), and bamboo (click-in or nail-down). Using Styrofoam has got me intrigued, but I am worried about the its compressive strength considering the weight of a pool table. So, what do you think of each of the following subfloor options for a bamboo finish? With a fair amount of space to finish, cost is a consideration, but doing it right is a bigger one. If I use Styrofoam, what level compressive strength will I need to ensure no long term issues with the pool table?
Option #1: Delta-FL (or Platon), 3/4 OSB – $1.00-1.30/sf
Option #2: 1/2 or 3/4 inch Styrofoam, 3/4 OSB – $0.70-$1.00/sf
Option #3: Delta-FL, 1/2 Styrofoam, 3/4 OSB – $1.30-1.60/sf
Thanks a lot.
Kurt – I would go with option #2. However, it’s important that you select a foam with a higher compressive strength. You can actually buy DOW Highload foam that has a compressive strength of 100 psi vs the normal 25 psi if you’re concerned about the pool table weight.
Since reading about your recommendations for Advantech, I’ve done a bunch of research and talked to their technical department. What a product, and what helpful people on the phone! Their normal recommendation is Advantech over a 6 mil+ polyethylene vapor barrier for a concrete floor. That’s it – wow. Of course, they were fine with either Delta-FL or Styrofoam for warmth. They said Advantech (3/4) can handle 500lb point loads. That would mean 2,000lb for a pool table. Since a heavy pool table is 1,000lb, no problem. Thanks for all of your help.
Kurt – AdvanTech is an amazing product. In fact, we won’t build a house today without it! Good luck.
Todd- What can you tell me about using Platon for a dry/insulating layer instead of foam? We didn’t consider foam until reading your article. Also, we want to install the subfloor layers before framing the basement walls. Should we put the foam boards on the cement block walls before installing the flooring layers? It has been recommended to leave a 1/4″ space for the flooring to allow for expansion when installing the subfloor over the Platon; is this necessary for foam as well? And I am not usre what pressure treated sleepers are and am unsure if it is necessary. Thanks!
Maura – It doesn’t “really” matter much which you install first although most would recommend doing the floor first. If you choose foam for the floor then run it up tight to the wall, leave a 1/4″ gap between the sub-floor and concrete/block wall for expansion. The sleepers are sometimes used and sometimes not used. It really comes down to a personal preference and there are many different variations of the same theme.
great article. I plan to follow your recommendations in finishing up my basement.
I have couple of questions that I needed help/clarification
As mentioned in one of your responses that I could go with foam and advantec board on top of it without using sleepers if height is an issue.But if i use less than 1 inch of foam, you recommend using poly first, then half inch foam and then 3/4 advantec.
Can you elaborate on the poly and its installation ? I mean what product do you recommend and how would you install it ? anything to look for ?
also what do you for the mechanical area ? leave the concrete floor exposed ? My furnace and water heater are tucked in corner. Also what do you with the walls around them ? right now i have fiberglass blanket against the concrete walls installed by the builder ? I plan to get the finished part of the basement, spray foamed (closed form) for 2 inches but since there is not much space behind the furnace and the water heater, I am not sure what to do with it. what do you recommend for both the floors and the concrete walls ?
Thanks so much for all the info
Tariq – When you use thinner layer of foam you need to install a vapor barrier. Thin layers of foam just aren’t thick enough to stop water vapor movement. You can simply install a layer of 6 mill poly on the slab and tape all the seams. Then you can install the layer of foam followed by the sub-floor.
As far as your mechanical room it’s really a matter of compromise. Do you want to remove the furnace? Probably not, so it may make sense to leave the existing insulation in place unless you suspect some type of mold problem.
You’re on the right track with the spray foam and floor insulation. You just need to compare pricing and what options are most important to you. Good luck.
Todd I live in Lubbock Texas had a lot of rain basement is leaking had about 36 gallons of water I wet vac.up. Friend of mine said to use swimming pool paint to seal the basement floor and walls. But I was reading some other blog not to use it because pressure would build up and shift the foundation. Any Idea what to use to seal it with?
Mark – You actually need to fix the drainage problem. It’s almost impossible to “seal” out water due to the pressure. I would recommend a sump pump system or exterior drainage improvements.
Todd
Thanks for the great article and advice. Is it recommended to apply a concrete waterproofing paint such as Drylock prior to putting down the 6 mil poly and foam board? Or is it necessary to let the concrete floor breathe I am reading conflict opinions on this topic.
Joe – First off thanks for the compliment. Concrete doesn’t need to breath contrary to popular belief. In fact, concrete needs water in order to continue the chemical reaction that creates strength. So concrete frankly likes water!
I don’t think using a sealer is necessary. I think as long as you put down the foam and seal the seams well there will be no issue.
Todd
I have a few questions. I am going to put 1″ T & G pink board on the basement floor with 3/4″ T & G treated OSB on top of that and then use tapcons to screw it directly into the concrete.
1. Is the pressure treated sleeper level that you recommend truly necessary or is my method going to be equally effective?
2. The house is about 7 years old and there are minor settling cracks from one side of the basement to the other (no evidence of any water problems) Do I need to seal/repair these cracks before I put the pink board down?
3. When I lay out the pink board does it matter if the OSB subfloor is layed in the same direction, or should I avoid having the seams of the pink board be directly under the seams of the OSB (obviously the seams of the pink board will be sealed)
Thanks
Chris
Chris – There are many variations on the floor and yours is another method that many people use. I would definitely seal any cracks before you start, better to be proactive than wish you had later. Be sure to seal the foam seams. I would try your best to avoid overlapping seems but it’s not necessary. Good luck.
Hi, great site Todd.
I have a question on building a subfloor.
1.5 inches of foam seems to be the general consensus to make a vapor barrier. So if I use 3/4 or 1 inch foam this is not a proper vapor barrier, correct?
My floor is about 6 ft below grade, which is also below the frostline. I’m guessing that 3/4 XPS, which is R4, should be enough to prevent condensation because the ground temperature should never get lower than 32 degrees. And also be a “good enough” vapor barrier if I seal it correctly and ensure the materials above it (Avantech & Carpet) allow vapor to pass (which should be very minimal to begin with). Is my thinking correct here or am I missing something?
The only reason I am considering 3/4″ is because nobody seems to stock 1″ in T&G anywhere near me and they won’t special order it because they have to buy it in pallets of 48.
Thanks,
Phil
Phil – You’re on the right track. The only other question is whether you have lots of moisture under the slab, do you have under slab drains? any signs of excess moisture? If it is dry historically then I say you’re ok.
Well, there is a lot of moisture in the ground, however I have drain tile on the inside and outside of the foundation and although my sump runs alot, I have never had moisture inside.
But since the ground is so wet I’m concerned about vapor coming up through the concrete. That’s why I’m leaning more towards something that allows a bit through rather than sealing it with a full vapor barrier like I did the walls. (I should have done the floor first, but I changed my mind on a subfloor after seeing how effective the foam on the walls is)
It seems to me that something like Dricore doesn’t offer enough insulation to stop condensation, and a full 1.5 inches of foam for a vapor barrier just gets to be too high. But then again, I really don’t know what I’m doing other than what I’ve read here and elsewhere…
Phil – Concrete doesn’t care if it’s wet, frankly it helps it continue to get stronger over time. On the other hand, carpet, flooring, etc don’t like water at all. What about applying a concrete sealer first, followed by the thinner foam?
I’m not too concerned about the concrete, but I am concerned about odor down the road.
The local building inspector recommends putting down poly first, then the foam and OSB. He thinks without the poly I will have too much dampness between the foam and concrete despite the fact that the foam will breathe some. I have also read about keeping the vapor barrier on the warm side however since vapor comes from the concrete in this case it may be a bit different. If I put a vapor barrier in anywhere then I can’t glue the foam or flooring down and have to tapcon, which of course pokes a bunch of holes in my vapor barrier anyway. And as I understand it, sealants aren’t any more of a vapor barrier than the 3/4″ XPS which has a permeability of about 2.
Maybe I’m just overthinking this, but I really want my basement to not smell like, well, a basement. The more I learn the more confused I get as all the locals seem to have different opinions.
Thanks for your help,
Phil
Phil – I can tell you we’ve done several basements this way and they all have worked very well. For me the key is always sealing the foam properly. I highly recommend Tyvek tape because it seals VERY well to foam board. Then you can seal around the perimeter with spray foam.
Sorry to keep bugging you, but when you say “this way”, do you mean vapor barrier, foam, then subfloor? Or sealer?
I used an off-brand version of housewrap tape on the walls because that’s all my nearest home store had. I think I’m going to re-tape it with Tyvek brand because it doesn’t seem to be sticking very well.
Thanks again,
Phil
Phil – I mean we’ve done several with just foam, seams sealed.
Thanks again for your help Todd.
Unfortunately, a nasty (and timely) thunderstorm caused a couple of leaks. I’ve had small periodic leaks from the windows and the first floor in high winds and every time I get it fixed it seems like another pops up in a year or two. So I gave up on the XPS idea and went with Dricore.
I’ll be putting it 1/4″ away from the wall foam and framing over the top. That way any future leaks will run down the foam and under the floor to dry out without hitting any wood on the way. Not the ideal solution, but probably better than future water getting in between the subfloor and foam.
Hi Todd,
I’m looking to finish my basement (w/ no water issues) using the foam board insulation and framing recommendations you’ve made along with a Dricore subfloor with carpeting. The Dricore website recommends building the frame on top of the Dricore. I had an idea to modify your method and I wanted to run it by you.
I was thinking of covering the walls with the foam insulation and sealing it with Tyvek tape and spray foam like your recommend. Then I would lay down the Dricore and get that set in place with a small gap from the wall to allow it to breathe. Then frame on top of the Dricore as per their recommendations. This should eliminate the need for either the composite decking base or for any pressure treated lumber. What do you think?
Todd – I think it sounds like a good plan. With any of these things each situation is always a bit different. Good luck.
I am designing a house and looking at how to insulate the basement floor in the walkout basement which will be used as living space (including the master bedroom suite). I have the following questions about your described design.
1. You recommend glueing the foam board to the concrete. I was considering putting Delte-FL between the foam board and the concrete
to better handle moisture should that become a problem (I plan on using 2″ XPS). Is this a bad idea (will it make the floor to unstable or is it just a waste because exposing the XPS to moisture is never an issue).
2. You recommend putting in sleepers, which concentrates the floor weight on particular sections of the foam board. Can the sub-floor be placed directly on the foam board and screwed into the concrete?
Please comment on these, both as independent ideas and used together.
arch – There are so many different ways to approach this topic and frankly many of them are good solutions.
1. Moisture isn’t an issue with xps when it’s thick enough so using the Delta-FL frankly is added expense for really no gain and it adds more overall height.
2. You can screw the sub-floor through the foam and into the concrete. However, that will require far more “concrete” anchors. If you install sleepers there are fewer anchors but you need to nail/screw the sub-floor down to the sleepers.
XPS foam can be purchased in at least two compressive strengths. When used in high loading situations you can use the higher PSI version to compensate for the higher loading.
I am not worried about moisture coming up from the concrete through the XPS. I am worried about what happens to water that otherwise makes it past the waterproofing strategy used throughout the basement (or should a toilet overflow, fish tank leak, etc). As stated on another website, the Delta-FL would preserve small drainage channels under the foam board that would provide an air space for drying (and a path to a drain if the problem was severe enough). Height is not a problem as this is new construction that can be sized as needed (and Delta-FL is only 5/16 thick).
Given gravity and water’s clever way of exploiting any imperfection in any seal, if water is introduced into a system where XPS is glued to the concrete, wouldn’t that water get trapped somewhere where there is little mechanism for it to dry or drain out?
Arch – I don’t discount those worries. However, small amounts of water won’t hurt concrete, it actually makes concrete stronger. The real issue with water is will it cause mold and mildew to grow. If water gets under your floor you need to worry about any wood, carpet, etc that has “food” for mold. Without the food, there will be no mold. Again I don’t think it will hurt anything to use it, I just think it’s a bit of belt and suspenders. I’d rather spend that money on a better exterior waterproofing membrane.
Hi, thank you for such an informative website. I am wondering if what I want to do is a good idea or bad idea:
We have a basement in Maine that is unfinished. I am thinking about installing the foam insulation against the walls and installing 2x4s, and some sort of paneling like you did for your storage room. However I am not sure if I want to insulate the concrete floor or install a floor as the basement is a computer lab/storage room/workout room. Also I probably will not install any type of ceiling. Is this insulating the walls and putting up walls a waste of money if that is all I do?
Thanks again,
James – Not a waste at all. Basement walls are typically about 50 to 60 degrees year round. If you think of them as a large radiant heat/cool surface then it’s pretty easy to realize that insulating the walls is a good idea. I would insulate any walls that you can afford to do.
I forgot to add this question as well:
Should I also insulate and frame/wall behind our furnace/oil tank? Our furnace is in the corner of the basement.
Hi,
I have put 1 inch foam and 3/4 inch advantech as my sublfoor in my basement. Most of the basement would be carpet except for the bathroom and bar. Initially I was planning to put tiles in the bar and the bathroom area over 1/2 inch cement board but the carpet installer who came to take measurement was concerned that the tiles would crack because of the foam present under the Advantech ?
Do I need to be concerned about installing tile over this subfloor ? or there any additional steps i need to take to make sure tiles would work ? are there any other products that I can use in a bathroom with shower ? Can I use laminate flooring instead ?
Any help would be greatly appreciated.
Thanks,
Tariq
Tariq – Couple thoughts.
1. There are some pretty decent sheet vinyl products today that would work well.
2. There are groutable vinyl tiles on the market today that look very nice, get the look of tile without the cracking potential.
3. Could install the high density foam in those areas, then be sure to screw the 3/4″ floor down very well, probably 12 to 18 inch centers, in addition I’d probably use an underlayment like Schluter Mat.
Hey Todd,
First of all great site. I have a couple of questions hoping you might be able to help me with.
Remodeling my basement, on top of the concrete floor there is an asphalt tile that is a real pain to get off was wondering if I had to remove that before putting the floor down?
If I used the high density foam would that be enough strength to support a bar?
Also the floor has sunken in floor drains and the floor is not level in those areas(slopes about 3ft around the drains, drains are sunken in about 1″) do you have any recommendations for this.
I planned on putting a layer of poly on top of the tile(have moisture problems on occasion). Then 1/2″ foam on top with 1/2″ subfloor on top of that.(Height issues)
Thanks for your help,
Frank
Frank – Sounds like you’ve got some challenges. First off not sure exactly what an asphalt tile is. I’d be a bit concerned about foam sitting on asphalt as they two typically don’t get along very well (asphalt has a tendency to eat foam). Aside from that if it were me, I’d get up the old tiles, level the floor (either self leveler or wood sleepers), then foam, then sub-floor.
Todd,
I have a basement floor that slopes towards a drain in the middle. It seems the original owner intended on using this room as a garage. It poses a challenge for me to get the floor level before I install a sub floor.
1. Would you suggest using self-leveling compound in a situation like this, or something else?
2. Is it OK to bury the drain in the middle of the room with something like self-leveling compound?
Rich – Self leveler will work fine. I wouldn’t bury the drain, I’d extend it if possible and put in a floor drain plug. Never know when you might need it.