If you have or will have an unventilated crawlspace, then your best approach is to seal and insulate the foundation walls rather than the subfloor. The advantages 6) Install rigid foam board or batt insulation—exterior foam, interior foam, or interior batt—to achieve complete insulation coverage. Insulate the

Installing an air gap subfloor with subfloor panels will help to control moisture from concrete floors that may contribute to mold formation. You can increase airflow to control moisture easily by increasing the space between subfloor panels and the wall edge. Running air duct vents down wall cavities to the floor level and

DIYNetwork.com experts show how to install a subfloor in preparation for tile flooring.

DIYNetwork.com explains what subflooring material works best with a variety of different flooring and they tell you how to install it.

Moisture content in the subfloor should be low before installing underlayment. In some cases a vapor barrier should be used between the subfloor and the underlayment, particularly for first-floor applications when using particle board underlayment over a subfloor other than exterior-grade plywood.

Installing Plywood Subfloor: Plan Ahead. Plywood is rated for use, based on whether it's for interior or exterior applications, and what type of material you plan to use for the finished floor. Available in standard sheets of 4 X 8 ft (1.2 X 2.5 m), your work will be easier if you minimize the number of cuts you need to make to

Exterior plywood accepts tile, without swelling up like interior-grade plywood. Since cement board is cheap and easy enough to lay down on plywood, it makes little sense to skip this step. However, if you would like to install tile on plywood subfloor, it is possible. In short, you would put down two layers of

Oriented strand board, or OSB, and exterior-grade plywood will work if first covered with a latex-modified mortar and a tiling backerboard. 3. Attach and arrange cement-based backerboard. cement-based backerboard - Subfloor Ceramic Porcelain Tile Installation. Tips: When you're working on any tile subfloor project, you

Read this article from home improvement expert, Danny Lipford, to find out if you need to apply cement backer board before tiling over a plywood subfloor.