I'm new here, and glad to find folks who enjoy and are willing to discuss home ownership issues. I'm trying to be nearing retirement (if that exists anymore in the USA), and have basic tool skills, if given the proper guidance and supervision...
I'm beginning a major kitchen remodel with new counter tops and floor changes. The floor now has linolium squares which was installed over Luan plywood, which is over 3/4" fiberboard, which was layed over a thin (1/2 or 3/8" maybe) ply subfloor over Southern Yellow Pine joists. The Luan was put down because the contractor didn't realize that linoliun won't stick to fiberboard. Why he used fiberboard in a kitchen to begin with is anybody's guess.
We want to install a tile floor (porcelin probably), and I want to replace the fiberboard with plywood.
In removing the old subfloor, I'm planning to use a finesaw to make a vertical cut through the fiberboard at the baseboards, under cabinet toespaces and around an island in the center of the room.
Several questions come to mind AFTER the de-struct is done:
1. Do I need to somehow connect the new plywood to the under-plate/cabinet/island stub of fiberboard?
2. If I use Ditra to save weight, compared to USB, can I get away with laying 5/8" ply instead of 3/4" ply subfloor. I like the vapor barrior part of Ditra, and the reduced height of the finished floor, and, the de-coupling action that it attempts to provide from subfloor movement. If the old subfloor does have a 5/8" base (under the fiberboard), another 5/8" ply would give new subfloor of 1 1/4" to support the new tile. Is that thick enough?
3. I'm thinking that I should attach the new plywood with the old base layer with glue and screws, but am not sure what spacing I should use between the screws, and if they should be deck screws or drywall screws.
Am I on the right track here?
Any words of wisdom or heads up on potential gotchas will be welcome!