I have read here about the need for 1 1/4" of wood under ceramic tile flooring, and wondered if the rule applies equally to all tile sizes. We are looking at two tiles for our kirchen, a 6" and a 20". I can see the 6 incher is going to be more work but if the chance of cracking was less it would be worth it. It seems like it would but I'd like to hear from someone with more knowledge than "seems!" tom
tile size and subfloor
Dec 06, 2004
2 Replies
You don't need 1 1/4" of wood. What you need is a *non-flexing* subfloor regardless of tile size.
How thick you need is a function of type (ply/plank/other) and the spacing of whatever is supporting it. For example, if it is a slab you don't need anything.
And you don't want to apply the tile directly to wood...if you have a wood sub-floor you want a cementatious layer (cement board) on top under the tile.
The larger the tile used the more important levelness of the area to which it is being applied becomes.
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You don't need 1 1/4" of wood. What you need is a *non-flexing* subfloor regardless of tile size.
How thick you need is a function of type (ply/plank/other) and the spacing of whatever is supporting it. For example, if it is a slab you don't need anything.
And you don't want to apply the tile directly to wood...if you have a wood sub-floor you want a cementatious layer (cement board) on top under the tile.
The larger the tile used the more important levelness of the area to which it is being applied becomes.
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