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.
Bring in the subfloor panels to the space at least two days prior to the installation so they climatize to the relative humidity of the room (Image 1).
Dry fit subfloor panels to see how they lay out (Image 2). This prevents ending up with a small sliver at the end. To adjust the panels, cut some inches off the starter row using a table saw. Cut in a well-ventilated area.
Add temporary 1/4" spacers between wall and the subfloor panels to allow room for expansion and contraction (Image 1). These will be removed after the floor is installed.
Use a tapping block to ensure a tight seam (Image 2). Stagger the seams for a more stable floor (Image 3).
If there is a deflection in the floor of less than 1/2", stack up as many leveling squares as needed and check to make sure the panels are level. If the deflection is more than 1/2", concrete repair will be needed.