Nailing Into the Concrete Subfloor by Hand

• You can install sleeper framing over a concrete subfloor by using 2-by-3 or 2-by-4 dimensional lumber laid sideways and nailed directly into the subfloor by hand. This requires quite a bit of effort, as well as special nails such as ring shank nails for masonry use, or cut masonry nails. This method is inexpensive, since the only tools required are a hammer and nails, but you will exhaust a lot of effort doing it this way.
  
  

Nailing Into the Concrete Subfloor With a Nail Gun

• Powder-actuated fastener guns use a .22-caliber rifle cartridge without a bullet, and they will blow the special nails directly down into the concrete. This is much faster, but requires the special gun and the special nails, which have a plastic fin around them that holds them in the barrel of the gun until they are fired.
  
  

Install a Waterproof Membrane Over the Floor

• Install a waterproof membrane over the concrete subfloor before installation of the nailed sleeper framing. Use a heavyweight plastic or a waterproofing membrane specifically designed for the purpose. You can then place the sleeper framing over top of the membrane at 16-inch-on-center intervals and prepare for nailing.
  
  

Install Plywood Subfloor

• Once you have secured your waterproof membrane and the sleeper fasteners, cut and nail your plywood subfloor of at least ½-inch thickness on top of the sleeper framing, similar to installing a regular plywood subfloor over joists. Then you can install your wood or tile floor without having to worry about moisture.