Hardwood and Marble Tile over Cement

[rick_keeter]

HI...I just bought a condo and want to lay hardwood and tile on the floors. The floors are cement slab on the top floor of the building. I really do not have moisture as I have done the rubber mat test. I have laid hardwood and tile many times but never over cement. I am wondering what my prep work has to be. Am I correct in assuming that I have to lay an asphalt felt layer and then 3/4 inch plywood on the floors where hardwood is to be laid? I can fasten the plywood using a powder actuated nailer, right? I am laying 3/4 " by 2 1/4 " hardwood. What length/gauge fastners should I use for installing the hardwood?

For tile, I can lay the tile directly on the cement slab, correct?

Please tell me if my assumptions are correct.

Thanks in advance,

Rick

[Rich]

Tile can be laid directly on the concrete but if the 2 flooring types are next to each other you may have some issues with transitions between the 2.
My suggestion for hardwood is either put the plywood down or get flooring such as Kahrs (sp?)(engineered) which can be laid directly on concrete.
With the 3/4" plywood down first your fasteners should be 1-1/8" - no longer than 1-1/4". Gauge - not sure - depends on what type of fastener you are using. If staples use 15 gauge - nails use a barbed flooring cleat.

[mjpliv]

I did a house 5-6 years ago with concrete overpoured floors and in-floor heat. We direct glued Anderson engineered hardwood flooring to the concrete with no problems to date.

One other concern about using 3/4" hardwood and plywood is creating an odd riser height on your stairs. This can be dangerous.