Latest Discussions : Flooring & Stairs

08:50AM | 02/27/07

Member Since: 01/17/07
48 lifetime posts

Subfloor and mastic question

I'm remodeling my kitchen and den and have found out that I need to remove a 1960's tile and vinyl before installing durock for a ceramic floor. I've discovered a "black mastic" substance on the subfloor. I know that it has to be removed. Is it going to be more cost effective to remove the current subfloor w/ mastic and replace it with a new subfloor? Thanks ahead of time.

Tileguybob

03:41PM | 02/27/07

Member Since: 07/03/05
283 lifetime posts

In the long run it may be better to lift that subfloor and replace it. The black adhesive, depending on how old it is may contain some asbestos.

In order to have a successful tile installation you will need a MINIMUM of 3/4" underlayment rated plywood (hint - CDX isn't) over floor joists that are 16" on center. The size of the joist will depend on its unsupported span but it should be at least a 2x8, much better if a 2x10. On top of the plywood you could set the 1/4" cement board like Hardibacker following their installation instructions by using thinset under the board and taping the seams with a fiberglass mesh tape.

fadedjeans

06:02PM | 02/27/07

Member Since: 01/17/07
48 lifetime posts

Many thanks for the advice!