How to Lay Wood Sub Floors
Filed Under Installing Wood Sub Floors, Replacing Wood Sub Floors, Wood Sub Floors
Many serious flooring problems can be traced directly to poorly installed wood sub floors. For this reason it is best to take the extra time to get your building’s foundation and wood sub floors done right the first time. For the same reason you should not skimp on your materials. Doing so will only cost you more in the long run after you have to repair or replace the inferior wood sub floor.
Wood sub floor materials have evolved over the years from dimensional plank lumber to particle board to plywood, the material of choice in a modern construction. The thickness of your wood sub floor plywood should be determined by a few different factors such as the spacing of floor joists, what type of flooring will be being installed and whether there will be an additional underlayment between the wood sub floor and the flooring.
The minimum thickness you should consider for your wood subfloor plywood is 5/8” on 16” centered floor joists but, honestly, ¾” really should be used if at all possible. You just almost can’t over do it at this point. The sturdier your wood sub floor, the fewer problems with damaged flooring from unstable bouncy sub floors.
When laying your wood sub floor it is absolutely necessary to be certain your first sheet of plywood is square to the foundation because every other sheet of plywood will key off of this first sheet. Orient the plywood sheets in such a manner as to span as many floor joists as possible while staggering the ends so no two sheets of the wood sub floor end next to each other in mid-frame.
Use an adhesive between the floor joists and wood sub floor material as well as between the plywood sheet edges even if they are tongue-and-groove. The plywood sheets should be attached to the floor joists with quality deck screws every eight to twelve inches, especially along the edges.
If you will follow all of these points when laying your wood sub floor, you will eliminate most of the problems of squeaky flooring before they start. Good luck and have fun.
