How to Install Subflooring for a Wood or Concrete Floor
Find out what subflooring material works best with a variety of flooring, then learn how to install it.
Pull up and remove the old floor so the wooden subfloor is exposed and cleaned. This may require dirty, physically demanding work.
Attach number 30 asphalt felt to the wooden subfloor. Begin in a corner of the room, unroll the asphalt felt and tack it to the floor using 1.5 inch galvanized finish staples in the pneumatic stapler attached to the compressor. A manual stapler could be used as well, but if the project is large, a pneumatic stapler saves a lot of time. Staples should be galvanized so they won’t rust over time. At the end of the room, cut the asphalt felt with a utility knife and begin the next adjacent row so that it overlaps the previous row by two inches.
Apply the metal lath to the floor, unrolling it in the opposite direction of the asphalt felt so that the two cross. The lath should also have a two-inch overlap (Image 1). Use a hammer to flatten the overlap so it does not stick up. Secure the lath to the floor with the stapler and the same galvanized staples. There should be approximately 20 staples per square foot or a staple every 2 inches. The metal lath should be securely attached to the floor; there should be no give when you press on it. Piece the metal lath together so it covers the entire floor (Image 2). Cuts should be made with wire snips.
The first layer of the concrete floor is made of Texture Pave, and will constitute most of the thickness of the floor. Texture Pave is a self-leveling cement topping, which is typically used for stamped concrete overlays, but here it's used to create a solid concrete base. Mix the Texture Pave in five gallon buckets. For each 55-pound bag of Texture Pave, mix four quarts of water. Mix using the paint mixer attached to the 1/2-inch drill. Coloring can be added to shorten drying time, but it is not necessary for the base layer.
Mix the Texture Pave and pour it onto your prepared floor one bucket at a time (Image 1). Set the gauge rake to a quarter of an inch. The gauge rake is a specialty tool used to drag across the top of the metal lath giving an even depth of concrete across the floor. Be sure to get the cement into the corners of the room. In hard to reach corners, spread it using the squeegee or a 1-1/2 inch putty knife. Smooth the marks the gauge rake leaves behind it with the squeegee (Image 2).
Allow the Texture Pave to dry for 10 to 20 hours. Once completely dry, the floor will be lighter, uniformly colored and ready for the skim coat.