Using Ceramic or Carpeting Over CDX Plywood (Subflooring)

Using Ceramic or Carpeting Over CDX Plywood (Subflooring)


When using CDX Plywood and if you have hardwood floor of different widths and lengths compromised of two layers. Each layer should act independently of each other in regards to how it constracts and expands. If you might have noticed, hardwood on a wood surface will expand when it's humid and shrink when it's dry or hot.

Replace hardwood with Exterior Glue Plywood with the minimum thinkness of 3/8's of an inch. Fasten according to APA guidelines, and then from this point on you can use either an uncoupling membrane or install the tile directly to the cdx plywood. The cost of uncoupling the membrane will be money well spent, as you will find.

Using grout sealer will not make the subfloor or the ceramic waterproof, the only purpose of the grout filler is to reduce the effects of staining.