I want to put down ceramic tile over pressure treated 5/4 deck boards(exterior)I`m using waterproof construction glue then I`ll grout it.Will this work and how can I seal this to keep it dry underneith?(the deck has fall) Bill
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It wont work first your "subflooring" of 5/4 boards is not stiff enough to prevent movement and movement means cracking either the tile or grout. Second, after you have addressed my first concern, why not lay backer board down and thinset to that, then grout. Much better method in my opinion.
I don't think it will work Bill. Tile and grout don't really expand or contract at all, but your wooden deck will be moving around underneath it everytime the weather changes. The grout will crack and so to will a few tiles, I would imagine. All of this will allow water to be trapped on the wood surface to further complicate the matter. It's kind of like a stand of dominoes, one crack leads to another, and another... next thing you know there are so many problems you can't fix them all. The only type of waterproof decking material I've seen stand up is a glued down fabric. This site will give you an idea of what I'm talking about http://www.duradek.com/
sometimes board sometimes knot
Edited 10/19/2002 2:50:19 PM ET by GORDSCO
Bill
You better do a whole lot of researchin' son cause for you to even suggest this is...well....aint real..uhhhh. Just reasearch and ask more questions. You need to post more about the situation at hand.Pictures would really help. More details. First off.why you doing this and whats it for exactly? Is there anything above the deck? Below the deck?
You absolutly can not do what youre suggesting. You need a surface that doesnt expand and contract. ESPECIALLY outdoors. Is it a second story deck? If its a first story near the ground then rip the decking out and start with ........oiy vey
Good luck and be well
Namaste'
Andy
It's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
For research, one good place to start is with Michael Byrne's book "Setting Tile". Then pick up a copy of the most current Tile Council of America "Handbook for Ceramic Tile Installation" and the related ANSI spec. Go to http://www.tileusa.com for the latter.
Construction adhesive is not a good idea for setting tiles, especially exterior, as it lacks the bond strength to keep the tiles attached, especially when the subfloor is changing underneath. Waterproofing is also a big concern with exterior applications.
Like Andy C said, we need more info about the project.