Tile underlayment- new construction
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Tile underlayment- new construction
New construction, 11-7/8" I-Joists 16" O.C. 3/4" T&G OSB Subfloor Kitchen floor spans 14' between floor joist supports.
I want to prep for general tile, probably ceramic due to budget. 12 x 12 tiles, or 8 x 16 if I get fancy.
Is 1/2" Concrete Board sufficient on top of my 3/4" subfloor? Should I have even more wood before concrete backer board?
I want to prep for general tile, probably ceramic due to budget. 12 x 12 tiles, or 8 x 16 if I get fancy.
Is 1/2" Concrete Board sufficient on top of my 3/4" subfloor? Should I have even more wood before concrete backer board?
#2
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Backer board is not structural, the plywood is. FWIW, 1/4" backer board is fine for a floor. Hang tight for one of the pros to assess your structure and subflooring.
#4
Hi Nicholas,
When installed according to the manufacturer's specs I-joists meet min. requirements for ceramic/porcelain tiles. You can contact them to make sure your system is stiffer than L360 deflection. Normally I-joists come in at L-480, which is very decent.
3/4" OSB properly installed meets specs for ceramic tiles. More ply is always a good thing if you can do it. 1/2" CBU will do you no additional good, go with 1/4" or a membrane such as Ditra if you want to step up in quality.
Jaz
When installed according to the manufacturer's specs I-joists meet min. requirements for ceramic/porcelain tiles. You can contact them to make sure your system is stiffer than L360 deflection. Normally I-joists come in at L-480, which is very decent.
3/4" OSB properly installed meets specs for ceramic tiles. More ply is always a good thing if you can do it. 1/2" CBU will do you no additional good, go with 1/4" or a membrane such as Ditra if you want to step up in quality.
Jaz
#5
I-joists 16" OC should be fine. I would use 1/4" backer set in a mud bed. To be sure, you can add 1/2" plywood to beef up the subfloor. I usually shoot for 1 1/4" thickness to make sure there is no deflection between the joist that could give your tile a stress test. If thickness is an issue, you can go with a product like ditra that has a lower profile and is rated for your 3/4" subfloor and eliminate the cement backer board all together.
#7
And my response was relative to "plywood" overlay, not the size of the underlayment. 1/4" CBU is best for floors, but I was referring to beefing up the subflooring. Sorry for the confusion and not reading the posts correctly.
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Replying late here. They are 16" OC not 19.2".
The 3/4" T&G OSB SturdiFloor subfloor seems very beefy. I would add 1/2" Ply if it is necessary, but if the OSB alone is considered sturdy enough, I would just add 1/4" Concrete board. Would 1/4" Ply + 1/4" Concrete Backer be better than no plywood at all, or is 1/4" not enough to even matter? I ask because 1/4" is cheaper than 1/2" and if 1/2" is not needed, I don't want the extra expense.
The 3/4" T&G OSB SturdiFloor subfloor seems very beefy. I would add 1/2" Ply if it is necessary, but if the OSB alone is considered sturdy enough, I would just add 1/4" Concrete board. Would 1/4" Ply + 1/4" Concrete Backer be better than no plywood at all, or is 1/4" not enough to even matter? I ask because 1/4" is cheaper than 1/2" and if 1/2" is not needed, I don't want the extra expense.