Sub-flooring

[craignlisa]

Hey guys,

In the 17' x 17' kitchen/bathroom reno I'm doing I have completed the sub-floor. If you recall from my earlier entries I sistered-up the original sagging joists by gluing and screwing 2 x 6's to all of them, then I glued and screwed 3/4" plywood across the span. The floor feels as solid as a cement floor and the flatness is unbelievable. It "dips" by about 1/8 across a couple of 4 x 8 sheets. This could be the joint made by lining up the 10' joists end to end to acheive the 17' span. Nevertheless, it is still within tolerances-correct me if I'm wrong!

I have purposely left 1/8" expansion gaps between all sheets of 3/4. Do I now need to join them with a floor patch?

The customer wants ceramic on the utility part of the kitchen and in the bathroom. She wants floating floor everywhere else (dinette and hallway leading to kitchen). I figure the height of the ceramic with thinset will be 1/2". The ceramic tile guy wants me to use a cementboard underlay of 1/2" thickness. That'll total 1" in height. My floating floor is 3/8. Add the foam underlay and you've got 1/2" total. Do I use 1/2" plywood everywhere else and lay them adjacent to the cementboard? Assuming the heights will be equal and using a transition joint between the floating floor and tile, I think it'll look nice, but it is correct to do it like this?

Thanks,

Craig

[floorman]

Thats sounds like an awful lot of work.Does the customer want this to be the same heighth? If they did not specify this then i would use what is called a baby threshold at the doorway where the ceramic and the laminate meet,there would be a small difference in heighth right there at the transition.
Yes ,you prbably should patch those seams if for no other reason than to say that you did it, if it becomes an issue later on but i doubt that it would, but you never know.
The 1/8 dips in the floor are well within tolerances for most laminates.

Floorman
floorlayers union local 1310

[craignlisa]

OK Floorman and Thanks for the quick response.

That said,

Do I lay the cementboard underneath the future cabinet areas (which occupy standard 24" from walls) or do I install my new cabinets directly onto my 3/4" ply sub-floor then lay the 1/2" cementboard around them. If I do the latter isn't THAT a lot of cutting and sizing to fit this stuff around all these cabinets?

Before the cabinets are installed, I would like to simply lay the cementboard everywhere she plans to have ceramic plus or minus a couple of inches, then lay 1/2" ply everywhere else, staggering the joints as I go. Once completed, a plan view would resemble a puzzle. I could simply install the cabinets on top of this then get Mr. Ceramic to do his thing.

Can this work?

Craig

Ps It was a lot of work, but considering the lowest points of the floor were 2-1/2 to 3" below the rest of the floor and some of the joists were actually rotten, now the floor is level and flat and solid, I'd say it was worth it. The only downside was that I did it alone. From the demolition to now (only the floor is complete) I had no help so it took a heck of a bite out of the schedule (4 weeks).
I need a vacation!

[floorman]

Yea ,go ahead and put the durock in before the cabinets it will not only save time but you won't worry about dinging up the cabinets either.
4 weeks is a long time hope you figured that in with the bid.
Anything else let us know[8D]

Floorman
floorlayers union local 1310

[Tom McNall]

You need to have a subfloor that conforms to L/360 for ceramic tile and L/720 for natural stone.

Other wise you will get this:



Best of luck.


Have Fun eh?
Tom McNall
Great Northern Stone
www.greatnorthernstone.com
www.marblecleaning.net

[craignlisa]

Thanks Tom,

Incidently what is the definition of L/360?

Craig