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.

What plywood should I use for bathroom floor?

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.

How thick should bathroom floor be?

AreaRecommended SizesSmall shower floor1-inch squareSmall shower walls1-inch square to 4-inch squareModerate or large shower walls4-inch to 15-inch by 30-inchBathroom floor1-inch square to 12-inch square, or up to large-format

How thick should plywood be for bathroom floor?

Consider what the top layer of the bathroom flooring will be since some types of plywood are better suited for different flooring. For hardwood, tongue-and-groove CDX plywood rated AC with a 1/2- to 3/4-inch thickness is best. Specifically for subflooring, tongue-and-groove plywood is strong and will reduce squeaks.

How thick should plywood be for flooring?

Some experts suggest that 15/32-inch plywood should be standard if the underlying floor joists are spaced 16 inches apart or less, but slightly thicker 3/4-inch plywood should be used for joists spaced further apart.

Is it better to use OSB or plywood for subfloor?

The National Tile Contractors Association and the Resilient Floor Covering Institute both recommend plywood for subflooring and underlayment, because it doesn’t have the risk of swollen edges that OSB does. Plywood also has a slight advantage in stiffness, which means that subflooring panels need not be quite as thick.

Is 18mm plywood suitable for flooring?

Plywood is the desired material for use in domestic flooring, but this particular board is extremely multi purpose. …

Can I use 6mm ply for tiling?

Why use 6mm No More Ply on floors? 6mm No More Ply is a pre-primed tile backer board which provides a flat, stable surface ready for floor tiling. … The 6mm depth of the boards means there is minimum disruption to the height of the floor, so as to not cause too much of a height difference between adjoining rooms.

What thickness OSB should be used for flooring?

Wood Products For decades, 23/32″-thick OSB has been the most commonly used thickness of OSB subflooring. But a simple switch to 7/8″ panels offers several advantages for accommodating a home’s energy efficiency and for ensuring the performance of finish materials and the overall feel of the floor.

Can you use 7/16 OSB subfloor?

Oriented strand board, or OSB, is a wood structural panel that can also be used for flooring. It is made from shredded strands of wood pressed together with wax and a special adhesive, then hot pressed into a panel with up to 50 layers of strands. OSB can be used for subfloors, although it is not as common as CDX.

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What is the best material for a bathroom subfloor?

Plywood or enhanced plywood is going to be the best option for your bathroom subfloor. Although they are more expensive than OSB, they still hold up better in high-moisture areas.

Can you use plywood sheathing for subfloor?

Like Sturd-I-Floor, Rated Sheathing may be plywood or OSB. When used as a subfloor, Rated Sheathing typically requires installation of an additional layer of underlayment on top of it before finish flooring can be applied. The underlayment requirements vary depending on the finish flooring.

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.

Can 5/8 plywood be used on a floor?

Typically, new floor joists are spaced at 16″ on center. However many older homes used 24″ o.c. The National Wood Flooring Association recommends a minimum plywood thickness of 7/8 inch for joist spans of 19.2 to 24 inches and a minimum plywood thickness of 5/8 inch for joist spans of 16 inches or less.

What size screws 3/4 plywood subfloor?

The proper steel screw sizes for securing 3/4-inch plywood to the floor joists are #8, #10 and #12 screws. The number refers to the thickness of the screw. Each is available in lengths from 1 1/4 to 3 inches. Typically, the 3-inch variety is used to secure plywood subfloors.

Does plywood need expansion gap?

APA recommends a 1/8-inch space between panel edge and end joints. Plywood and oriented strand board (OSB), like all wood products, will expand or shrink slightly with changes in moisture content. If the wood structural panels are tightly butted, there is no room for expansion and buckling can occur.

Is 12mm plywood OK for flooring?

Due to our 12mm Hardwood Plywood being a structural product – it can be used in sheds for roofing and flooring too. An interesting application for 12mm Ply is Plywood pegboards – a quirky addition to any home, plus they’re super easy to build.

Is 18mm thick enough for flooring?

With the thickness of the floor being at least 18mm, you can be sure it is stable enough to go over joists. Fitting over joists can add extra pressure to your hardwood floor, but structural wood has the correct load bearing properties to cope with this.

Can you use 18mm OSB as flooring?

OSB tongue and groove 18mm boards are suitable and widely used in structural (manufactured in accordance with EN 13986) and interior applications, such as: Load bearing roofing & flooring applications. Hoarding. Wall sheathing.

How do you waterproof a bathroom subfloor?

Caulk any seams where two pieces of plywood are butted together. Dab caulk onto nail or screw heads to seal the potential leak point they provide. Caulk any splits in the wood or any other areas that may provide a point for water to seep under the subfloor.

Can you waterproof OSB?

OSB is strong and water-resistant. Every single fiber or piece of wood in an OSB is saturated with a cocktail of resins designed to provide superior strength and waterproofing to the finished product. … This type of board is an excellent material for use in waterproofing systems, be they roof, sub-floor or wall.

What's the best plywood for flooring?

Interior plywood is ideal for rooms not exposed to moisture, such as bedrooms, and makes a good subfloor for carpeting, tiles, vinyl, engineered wood laminate flooring and hardwood flooring. Exterior plywood is a better choice for bathrooms, kitchens and any other rooms exposed to water and moisture.

Which is stronger OSB or plywood?

OSB and plywood offer similar (and sufficient) performance in terms of strength and functionality, though plywood is about 7% stronger. … Plywood will absorb moisture quicker than OSB, but consequently it will also dry quicker.

Is OSB cheaper than plywood?

OSB is less expensive than plywood. To build a typical 2,400-square foot home, OSB may cost $700 less than plywood. OSB is considered by many to be a “green” building material because it can be made from smaller-diameter trees, such as poplars, that are often farmed.

Do you need to seal plywood before tiling?

24 Answers from MyBuilder Tilers Plywood requires the application of a latex based bonding solution to the plywood to seal it and then the use of a flexible cement based adhesive, not pre-mixed tub adhesive.

How strong is 7 16 plywood?

7/16 OSB, 24/16 APA span rating, 40 psf allowable live load. 15/32 OSB, 32/16 APA span rating, 70 psf allowable live load.

Is plywood sheathing waterproof?

How is Plywood Used Outdoors? Exterior plywood is weather (and water) resistant, so it’s strong enough to be used outside and also in areas that are exposed to water and humidity, like a garage. This type of plywood, often made from Douglas fir, is made stronger by adhering its layers with a waterproof glue.

What is the difference between sheathing and sanded plywood?

Sanded plywood features face and back (top and bottom) plies that are sanded in the manufacturing process. It is typically used where it will be seen such as for cabinets, shelves and paneling. … Plywood sheathing or structural plywood is designed for permanent structures.