How thick should subfloor be in bathroom?

Make Sure Your Subfloor is Structurally Stable

The installation guide for 1/4 inch HardieBacker recommends having wood subfloors made of 5/8 inch exterior grade plywood or OSB (oriented strand board) that is 23/32 inches thick.

What is best subfloor for bathroom?

Pressure treated 3/4″ plywood subfloor is the best subfloor material for bathrooms. Pressure treated plywood is water resistant and will withstand the humid, damp bathroom environment much better than untreated plywood or OSB.

How thick should your subfloor be?

The minimum thickness of plywood for subflooring is about 5/8 inch. Since it does not hold fasteners as well as plywood, OSB must be a little thicker, or at least 23/32 inch. There are several factors that determine what subfloor thickness is optimal for added benefits like insulation.

How thick should a shower subfloor be?

The subfloor needs to be a minimum of two layers of 3/4-inch exterior grade plywood before you can move to actually putting down the concrete layer of deck mud that provides the slope and the base for the shower pan tile.

How thick should a bathroom tile subfloor be?

The subfloor under the tile should be at least 1 1/8″ thick, with a minimum of 5/8″ thick exterior grade plywood topped by 1/2″ cement backer board.

Subfloor VS. Underlayment Explained

Is 3/4 subfloor enough for tile?

CLICK TO ENLARGE Plywood underlayment, glued and screwed to a nominal 3/4 in. plywood subfloor, makes a sturdy substrate for ceramic tile. The uncoupling (crack isolation) membrane helps prevent cracking in the tiles and grout.

Can you use 1/4 cement board on floors?

1/4" USG Durock® cement board is an ideal substrate for floor and countertop ceramic tile installations. The 1/4" thickness helps eliminate transition trim when abutting carpet or wood flooring and minimize level variations with other finish materials.

How thick should subfloor be under bathtub?

Subfloors typically consist of 3/4 or 1-inch thick tongue and groove plywood or oriented strand board. Cut the replacement floor using the circular saw along the marks made.

What kind of wood is used for bathroom subfloor?

Plywood as a Subfloor Material

Traditionally, exterior grade plywood has been the subfloor material of choice for many bathroom flooring projects. Plywood is made by gluing alternating layers of wood veneer. CDX plywood (¾”) in particular is used often because it has a high level of resistance to moisture and humidity.

Is 3/4 plywood OK for subfloor?

The spacing of the joists governs the recommended thickness of the plywood subfloor. Some experts suggest that 15/32-inch plywood should be standard if the underlying floor joists are spaced 16 inches apart or less, but you should use slightly thicker 3/4-inch plywood for joists spaced further apart.

Is it better to use OSB or plywood for subfloor?

OSB has a lower resale value than plywood due to its lower strength. For this reason, few homeowners prefer OSB in their homes. Apart from costs, plywood is superior in all the other areas, such as the strength of the structure. For this reason, it's a superior material for use on the subfloor.

Can you use half inch plywood for flooring?

Glue is sprayed between each layer and the sheet is hot pressed. CDX plywood should be a minimum of 7/16 inch thick. The thicknesses are as follows: 7/16-, 15/32- and 1/2-inch-thick panels require joists spaced 16 inches on center; 19/32- and 5/8-inch-thick panels require joists spaced 20 inches on center.

Do you need marine ply in bathroom?

The excellent moisture-resistant properties of marine plywood will also only be utilised to full effect in a marine setting, such as on a dock or boat. While taking a bath or shower is likely to disperse a small amount of water around the room, it is never to the extent which merits the use of marine plywood.

Should I seal my bathroom subfloor?

Every type of bathroom floor, including linoleum and other moisture-resistant materials, should be completely sealed around the edges where it meets the wall, bathtub, toilet, vanity and any other permanent fixtures.

Does subfloor need to be tongue and groove?

For subflooring, you use tongue and groove plywood. The tongue and groove are only along the 8 foot edges. On the four foot edges, your seams will fall on joist tops, so no need for tongue and groove. But to start off, we will need to remove the tongue so the plywood is tight with the exterior ICF walls.

Is there a waterproof subfloor?

Waterproof plywood for bathrooms is moisture-resistant and can be used for subfloors. You can buy the panels in home improvement stores and install them yourself, but keep in mind that many professionals claim that no plywood is 100 percent waterproof.

Is plywood good for bathrooms?

Plywood is suitable for both bathrooms and kitchens – if you use the correct plywood product, that is. Plywood with birch cores are the only suitable options and we at Maxiply highly recommend pre-finishing and an additional coat of UV oil.

Can my floor support a bathtub?

Bathtub Weight

Traditionally bathroom floors are built to withstand the pressure of an average bathtub (full), but in some cases the floor can be weak, or if you are looking at getting a larger tub, you might need to look into reinforcing the flooring.

Can I just screw down cement board?

Doing this will require that you remove the existing surface material before installing backer board over the studs. Cement board can also be used on countertops when laying tile. However, the process will involve using an extra sheet of backer board. Never use standard screws when installing cement board.

Should you cement board a bathroom floor?

If you're working over a wood subfloor, cement board is the right choice for your tile base. No matter what you're told at a home center, it's not a good idea to install tile directly over plywood, especially in a damp area like a bathroom.

Do you have to put thinset between subfloor and cement board?

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners. And you won't have the fasteners if you are trying to install it over concrete. On the bright side, there are some options for concrete subfloors.