I know you answered this 200 times. How about 201 I took up the old floor and have the old subfloor exposed. It is 3/4 inch plywood on a 2x8 16" center joist system. Can I put 1/2" cement board down on top of this then lay my tile or do I need more wood on this before the cement board? Can I use regular deck screws to screw the cement board down with? I know I have to use thinset to.

thanks, coach

I forgot, the kitchen is in the corner of the house. so the middle support beam is on one side of the kitchen wall holding up the joists. 12 foot is support distance. 60 year old house with some soft spots that I glued from underneith and screwed down. Not a bad start. Floor is solid now. I am a carpenter not a floor guy. The floor is a favor for a friend, trade for a fishing boat.

 

Here is a calculator used to determine the suitability of floor structurs for tile.

http://johnbridge.com/vbulletin/deflecto.pl

 

You need no more subfloor. 3/4" plywood on 16 o.c. joists with 1/2" cement board is plenty. However, this doesn't say anything about whether the floor is stiff enough. You cannot correct a bouncy floor with what you put on top of the joists if the joists are insufficient.

A 12-foot span of 2x8s 16 inches o.c. is slightly insufficient for a guaranteed installation of ceramic tile.

Do not use deck screws to install cement board. Either use the cement board screws or use roofing nails. The installation instructions of the cement board you select will tell you the appropriate fasteners and spacing, along with the proper type of thinset to put under it (varies by cement board manufacturer).

 

thanks, but will roofing nails pop. Is 1 1/2 inch long enough?

 

you can use 11/2 to 1/3/4 roofing nails but remember to ahere your cement board with latax modified thinset with a 1/4 to 3/8 inch notch trowel and tape your joints with fiber glass tape

 

another dump question, regular roofing nails or ringshank nails used for tin roofing? just don't want to screw up.

 

regular roofing nails is fine they will be galvinized

 

thanks a ton

do you know anything about changing the color of white grout?

 

Yes many groutcompanies like customs, tec, hydroment and mapei make a wide selection of grout color stains that are very easy to install and acts like a grout sealer to boot