I am a home owner with her very first remodeling project to expand the exisitng kitchen. A new plywood sub floor was built on the existing foundation to meet the raised foundation of the new added area. I will be laying infloor heating. What’s the best option to prepare the cold joint between the plywood subfloor and new concrete foundation. My flooring person put down some sort of dark plastice tape and ‘plaster like’ material on the top but it’s already crumbling as drying takes place. Looks like I cannot depend on him to come up with good solution. Thanks.
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Are you talking about a plywood to concrete slab joint? Where is the RFH going,under the plywood floor, or in the slab, both?
I'm not a RFH guy, so can't help you there.
This reply will serve as a bump to get your question back up on the list. Someone else may have a solution for you.
Dave
A flooring guy is the last you would want to ask for advice how to do radiant floor heat anyways. Who is your general contractor and why is he not handling this?
I am totally lost from your report here as to what you have how, where you are going with this, and why the radiant is not already in place. Something sounds backwards to me.
when you say "foundation" do you mean a slab on grade? I am trying to picture what this cold joint is and how all these elevation problems come to exist. What sort of foundation is this?
Then - when you speak of laying infloor heat, that implies pouring gypcrete, but again, I get confused over what is already there im my mental picture.
Is there a crawlspace and you plan to staple up the heat from under there?
Cold joint? ?
Cold joint?????
What have you got there?
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Thanks for responding. As you can see, I am homeowner rather than a builder and I cannot even speaking the lingo.
I have a joint on my floor where plywood raised floor is meeting with concrete slab on grade. There is no craw space. The plan is to lay the in floor heating (electrical heating mat type) above this and lay Ditra mat then the tile floor.
The joint between raised plywood floor and new slab is not very clean. While the area is leveled, there are some gaps. I am looking for information on what is best way to fill this gap and smooth out the area. I've heard that either thin set or grout material can fill the gap and lay 'crack proof' membrane.
Where is my general? I don't even want to go there!
Thanks in advance for any help.
OK, I have some of this picture now.Taht joint will always have some tnedency to move and separate. There are many different flooring levelor product you could use to skim it in. Levelite, Levelastic, etc...Make sure that the ditra spans on both sides of the joint. The decoupling action it provies is essential to avaoiding tile problems with this.Heat mat -
Make darn sure that what you are installing is a HEATing mat and not a warming mat. The warming mat will only warm the tile. It wil never heat the roomand - Make darn sure that you install it right according to instructions, then be careful to do nothing to damage iot while running th editra and tile over it.
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Thanks for the info. I feel much better for having gotten objective opinion.
Piffin,
In this case, would it make sense to run the heat mat in the setting bed over the Ditra? I think that may give the wire mat some flexibility over the joint, although it may not really matter with the Ditra....that's not a mistake, it's rustic
I don't have the experience to say on that. Probably pros and cons both ways. Marrying a wood to slab floor is not a great situation any way you look at it.http://www.taunton.com/store/pages/070209.asp Mike knows his stuff. I think he has his own website too. There may be somebody at the John bridge forums who could say more
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