2nd Floor Bathroom Subfloor Thickness

Using the right type plywood ensures a long lasting floor.

2nd floor bathroom subfloor thickness. If the joists are spaced 16 inches on centers or less the minimum required thicknesses are 5 8 inches for. When accounting for joist width subflooring flooring and standard ceiling drywall a floor framed with 2 by 10s will be very close to 11 1 4 inches thick. The same floor if framed with 2 by 12s will be 13 1 4 inches thick. Nail down or floating floors may be installed over existing vinyl as long as it s no more than two layers thick.

Typically made of plywood or osb and ranging in thickness from 19 32 to 1 1 8 thick the subfloor is truly structural second only to joists in this respect. Thoroughly vacuum the existing floor and use a long floor leveler and tape measure to ensure the subfloor is level within 3 16 inch for every 10 feet. Osb doesn t hold nails as well as plywood so an osb subfloor needs to be thicker. The floor must also handle the weight of the tub shower tiles and other fixtures.

The bathroom floor gets wet. Floor joists are made from 2 by 8 inch or 2 by 10 inch lumber or from engineered quiet beams which are made from a thin layer of chipboard on edge between two lumber caps forming an i shape.