Granite tile countertop questions

[jalrn57]

I have 2 questions that I could not find answers for. One is what type of plywood to use. My local Home Depot and Lowe's carry birch, oak and what they call indoor sanded project plywood. Which should I get? Also I have a busy home with teenagers who sometimes I think lose their common sense. When I get to the area of the sink can I pre-seal the tiles to protect them? Thanks for any help.

[Mark D.]

Plywood? For tiles?
Is this a floor, a counter or a wall?
If it is a counter you can use plywood but I like cement fiberboard over it, screwed in every 6 inches so it won't move much. The problem with just using plywood is if it gets wet and warps your tiles will start popping.

If it is a floor is the substrate concrete? If not, what is it?
If it is a wall try cement fiberboard instead of plywood.

Please post more info.

Mark

[jalrn57]

It is a countertop and I will use hardibacker unless someone here tells me different. I need to know what kind of 3/4 plywood. They have oak, birch and something they call indoor sanded project plywood.

[Mark D.]

If you are using plywood under hardibacker just use CDX plywood.
Mark

[jalrn57]

Do you use adhesive between the plywood and the hardibacker?

[Mark D.]

You can, but there is no need to do that.
Mark