How to Nail 1/4-Inch Plywood Subfloor

Plywood subfloor is installed over top of the sheathing to give a smooth and even surface for tile installation.

This 1/4-inch underlayment comes in 4-by-8 foot sheets and nails directly into the plywood sheathing underneath. It is used as a moisture barrier to help keep the subfloor from too much water damage. Installing an even and secure plywood subfloor is the first step in the installation process of a brand new floor in your home.

Measure the length and width of the room and multiply the two together to determine the total square footage. Divide that number by the square footage of a sheet of plywood subfloor which is 32 to get the number of sheets that will be needed for installation.

Line up the first piece of plywood vertically beginning at any corner of the room. Place the first 3/4-inch ring shank nail at the bottom corner of the first sheet leaving 3/8 inch from the edge of the panel. Hammer it in place and move 2 inches down the plywood. Repeat the process for the entire sheet. Insert a nail 2 inches around the entire perimeter.

Snap a chalk line diagonally from the corner where the plywood has been installed to the opposite corner. Hammer in nails diagonally along the chalk line every 4 inches into the plywood. Fasten the rest of the panel at 4-inch intervals around the entire sheet to secure it to the sheathing underneath.

Butt the second sheet of plywood subfloor directly into the first. Add nails every 2 inches around the perimeter and every 4 inches along the inside. Continue around the room nailing the plywood to the sheathing underneath until reaching the end of the first side.

Measure and mark the plywood with a pencil where the cut will need to be made. Cut straight along the line with a circular saw and a fine-toothed blade. Line up the piece and install it just like the previous pieces were installed. Move around the entire room until all of the 1/4-inch plywood subfloor has been installed.

Things You Will Need

  • Tape measure
  • Hammer
  • Ring shank underlayment nails
  • Chalk line
  • Pencil
  • Circular saw
  • Fine toothed blade
  • Safety goggles

Warning

  • Always wear safety goggles when working with a circular saw to help protect your eyes from flying debris.

About the Author

Alexander Callos began writing in 2005 for "The Lantern" at The Ohio State University and has written for various websites, including Bleacher Report, Top Ten Real Estate Deals and Columbus Sports. He has published articles for CBS Sports, SI.com and other websites. He graduated in 2007 from The Ohio State University with a bachelor's degree in public affairs journalism.