What is the best way to insulate a concrete floor than install a wood floor on top.
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Loaded question how much room do you have to play with?
Do you look to the government for an entitlement, or to GOD for empowerment. BDW
Find out if wood over a basement floor is recommended. I just laid a laminate floor over 1" of foam board and a sheet plastic dimpled product tapesealed at the seams. The floor thickness added was 1-3/8" before the laminate went down. It is important to keep moisture from the concrete from reaching the wood. It is important to let the moisture vapor move, hence the advantage of the dimpled plastic sheet. Consider the risk of the wood floor moving compared to other flooring products that are not affected by moisture.
I want to do this too in the basement of my 2 year old addition. It's new, smooth concrete basement with walkout doors and concrete walls about 4 feet high , then framed with windows. It's pretty dry down there, even on humid days (Connecticut by the way), but I haven't started until I get a better understanding of the right way(s) to do it. It will be a play-work room, so I could go with a cheaper "sheet good" type floor also.
Any ideas & suggestions are very welcome.
Edited 4/11/2006 10:08 am ET by homebrew
I did my basement about a yr ago. I am in RI, and I did the delta dimpled plastic sheeting, then covered with a tongue and groove advantec 5/8 ply. I painted my storage side with 4 coats of latex, and I am gonna cover the play side with carpet and vinyl at the entrances.
I love the product and the result. Extremly dry, and even keeps the floor warmer. Was very easy to install. We have a walkout basement, so with this product, it really makes it feel like an upstairs room, you don't get the basement feel of dampness, smell, nothing.
Let me know if you have any questions.
regard
joe p
Might help if "we" know a bit more.
Like where your location is, in general if nothing else (profile information helps, hint, hint).
You ask about insulating a concrete floor. What sort of floor is it? A slab-on-grade floor is different than a basement floor, is different than a to-be-converted garage floor.
"Insulation" suggests that you find the floor either too cold or too hot--is that the case? It could be that all you need is some radiant heat in the floor.
Tell us more, and we can narrow the answers down.
The room I,m doing is and old garage attached to the house the old floor has sagged in. So we are going to take out the old floor dig down to the footing .and fill with stone than pour a new slab. Then tile one side for a mud room. The other with a wood floor.The walls go down 48"to a footing we live in Vermont.
Put down plastic sheeting before you pour the concrete then finish as normal. Then take 4 X 8 sheet of plywood (pressure treat), cut each sheet in half to get 4 X 4 sheet then glue these direct to the new concrete. The floor glue also helps keep the moisture out too. Don't use thin beads of glue, buy it by the bucket and spread as you would with thinset and tile application using notched trowel. Leave about 1/2 space all around each half sheet of plywood then let dry and start your floor app when the adhesive is dry.Did a slab floor that way and it came out just great. You can even add another layer of felt paper on top of the plywood before attaching the wood floor if you want to be super safe.
First off no solid flooring below grade no matter what you do.
Secondly no one mentions checking moisture conditions (MVE of the slab) or checking site conditions. Another important thing to mention is the slab must cure at lest 90 days.
There is so much on the web about how to do this properly - and there are so many floors that fail b/c they are done improperly.
Also most trowel glues do not specify that they retard moisture. MVP or Lockdown is better for this however they are only specified for gluedowns - not floating or attached subfloors - I am sure they'd still work fine. I'd do a 2 layer floating subfloor over a glued down single layer.
If your using felt to retard moisture - I'd think again. While felt may retard some moisture it is used mainly to stop creaks and pops.
Fox said it was a garage floor and made no indication that it was below grade. We use Bostick's stuff and it is great, been four years now and floor looks almost as good today as it did when we put it down. Moisture barrier installed below slab which is what was suggested.Some do and some only talk about it.
I hear you that your way worked, but there's more to it and may very well not work in this situation.
If you do not check for moisture then you are gambling. Even if poly is under the slab - this does not mean the slab will not emit too much moisture. There are dozens of ways moisture could enter into the slab - improper grading is the most common w/o perimeter drains.
Using Bosticks is fine but it is not made for that application - check out the label. Using MVP or similar is better IMO. As well as a floating subfoor as well. Also the slab must cure for at least 90 days.
Not to knock your method - I believe that there are better more complete methods to insure a sucessfull flooring installation.
The floor is just above grade. What about insulation under the sub floor? Foam between sleepers. Ply on top. 3/4 T&G.
Don't know how important slab insulation would be in your application but you could probably put down an inch or so of foam under the plywood then top it with your T&G floor. You have to watch how thick everything is starting to get, 1 inch foam, 3/4 inch ply and then floor is getting up to around 2 1/2 inches total. Bostic has a trowel applied sealer for water that you should apply first then adhesive for the rigid foam. I don't know how well all that would work, I'm sure you could get it down but would it be stable enough for the hardwood floor? I think it would be just fine but I don't have experience with a three layer sandwich foam-plywood-hardwood floor set up . It worked out fine with just plywood-hardwood floor but that's in California where thermal transfer through slab is not a serious problem...As I recall, aren't you replacing the entire slab? Why not install the plastic barrier under the sand base followed by rigid foam insulation around the perimeter and in about two feet from the edge of your floor. Then, pour your slab on top of the rigid foam edge and sand layer. This would give you the insulation value you need and you could proceed just as we did, using Bostic sealer/ adhesive combination under the 3/4 treated plywood and install your floor on top of that. This gets you to what you want and it's a proven method that should work just fine.
http://www.hardwoodinstaller.com/hardwoodinstaller/hardwoodonconcrete.htm
Here are the best practices for installing over concrete. These are what has been proven effective over the years. With the advent of Bosticks MVP and Taylor's product things are changing to get even better. While poly under the slab is important - it will not completely stop moisture vapor from emitting from the slab. You really need to http://www.vaportest.com test your slab before installing your floor and allow your slab to cure as well - at least 90 days.
I have been asked by another publication to write a short article on how to do this properly - unfortunately not for a few months.
Fox - you can do sleepers on 12" centers and bed them in mastic after you deal with your slab. You can run your flooring just off the sleepers. You could add your foam there if you wanted minimizing the big height gain.
Woodway - why use PT lumber if your glue is sealing the moisture? If your worried about your subfloor coming in contact with moisture - how is your wood floor not going to be effected. Felt slows moisture transmission but should not be considered a moisture barrier; especially after you popped 10000 hole in it nailing your flooring.
Check out the MVP product - I've glued 5/8 solids to slabs (first sealing with MVP) with no problem. Some installers are even treating regular wood subfloors over crawlspaces for that extra insurance instead of poly barriers that usually get destroyed in the crawlspace.
Edited 4/13/2006 1:22 pm ET by dave northup
Edited 4/13/2006 1:23 pm ET by dave northup