Asked by: Craciun Tegelaar
hobbies and interests woodworking

What thickness should a subfloor be?

Last Updated: 23rd March, 2020

37
the subfloors need to be thicker. For joist spacing of more than 16 inches up to 19.2 inches on center, the minimum thickness for both plywood and OSB is 3/4 inch. For joists spaced more than 19.2 inches on center, the minimum thickness for plywood is 7/8 inch and for OSB, 1 inch.

Click to see full answer.

Keeping this in consideration, what thickness of plywood is used for subfloor?

The thickness of your plywood subfloor depends on the joist spans. The National Wood Flooring Association recommends a minimum plywood panel thickness of 7/8-inch for joist spans of 19.2 to 24 inches, and a minimum plywood panel thickness of 5/8-inch for joist spans of 16 inches or less.

what should I use for subfloor? Plywood has been a standard subfloor material since the 1950s and remains the preferred subflooring for many builders. Standard plywood can be used for subfloors, but a better material is 3/4-inch tongue-and-groove plywood subflooring.

Simply so, how thick should a floor be?

In a typical home, the entire structure between levels can be about 12 to 14 inches thick, depending on the type of joists used and the finish materials for the floor and ceiling.

Do you nail or screw subfloor?

When you use a nail gun to attach subfloor sheathing to the floor joists, the nail sometimes misses the joist. Remember, nails can pull up; screws don't. This gives us stronger floors that will not move or squeak.

Related Question Answers

Ava Cyrenius

Professional

Do I need to glue plywood to subfloor?

On the 3/4" subfloor, you have the right idea. Use subfloor adhesive, and screw 8" at edges, 12" in field. For the 1/2" underlayment, ideally, you want to screw every 6" all across the panel. Adhesive will help you here, as the subfloor plywood will have voids in spots that will not hold a fastener.

Lifang Kanmani

Professional

What screws should I use for subfloor?

Steel Screws
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.

Celsa Boo

Professional

Should underlayment be glued to subfloor?

No, you should not glue down your underlayment. Underlayment is is a floating material, the same as your laminate flooring. In most cases, you should not glue or nail your underlayment down. You should always check with the installation instructions of the underlayment for proper installation instructions first.

Fatna Mallorquin

Explainer

How do you fill gaps in subfloor flooring?

Fill Plywood Subfloor Gaps
An effective strategy for filling large gaps is to mix patching compound to a stiff, mortar-like consistency, trowel it into the plywood subfloor gaps and wait for it to stiffen before troweling it smooth. Some sanding may be needed when it sets completely.

Zahia Sangenis

Explainer

Can I put new subfloor over old subfloor?

One of the benefits of removing the old flooring is it allows you the chance to fix any loose subflooring or squeaks by re-securing the main subfloor to the floor joists prior to installing the new flooring. With all that being said though the answer is YES you can install New Wood Flooring over the old.

Xiuhua Galbarriarto

Explainer

What is better for subfloor OSB or plywood?

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.

Alba Ribalow

Pundit

What is the best subfloor material?

Hardwood flooring: Plywood is the best subfloor for hardwood flooring installation. CDX plywood ranging from 1/2 to 3/4-inch-thick and rated A/C will serve well for any hardwood flooring installation. Tongue-and-groove plywood is available to reduce squeaks and help the subfloor fit together better.

Neco Yzazelaia

Pundit

How many layers of plywood do you need for a subfloor?

There are several methods, including: Floating subfloor: There are two common methods for this. The first is to lay two layers of 3/8-inch plywood over the slab without fastening or gluing them to the slab. One layer is laid, and the second layer is stapled or glued perpendicularly or diagonally over the top.

Ayan Matanza

Pundit

What is the best subfloor for a bathroom?

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.

Ortensia Meyerrose

Pundit

Do you have to use tongue and groove for subfloor?

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.

Maricarmen Malewsk

Pundit

What is the space between two floors called?

An interstitial space is an intermediate space located between regular-use floors, commonly located in hospitals and laboratory-type buildings to allow space for the mechanical systems of the building.

Sharda Hurnaus

Teacher

What is the best thickness for wood flooring?

Most are 3/4" thick, although some manufacturers also offer a “thin- profile” solid that is 5/16" thick.While solid hardwood flooring is typically nailed to a subfloor, thin-profile solid flooring can be glued down over concrete and other hard surfaces.

Zina Imwolde

Teacher

Can floor joists be 24 inches on center?

Proper Spacing. As with the joist size, the building code for your structure will stipulate the proper spacing between floor joists. Given that 2x8s are actually 1-¾ inches wide, it works out to be 14-¼ inches between each joist. With some structures, floor joists are required to be 12 or 24 inches apart on center.

Elisenda Kodesh

Teacher

How thick is concrete between floors?

Standard concrete floor slab thickness in residential construction is 4 inches. Five to six inches is recommended if the concrete will receive occasional heavy loads, such as motor homes or garbage trucks.

Patrizia Rolves

Reviewer

What is the average height between floors?

What is floor to floor height? - Quora. The height of each storey is based on the ceiling height of the rooms plus the thickness of the floors between each pane. Generally this is around 10 feet (3 m) total; however, it varies widely from just under this figure to well over it.

Unni Nonlodico

Reviewer

Can I use drywall screws for subfloor?

Drywall screws should only be used for drywall, and a temporary coat hanger. You want more strength and need less space for the threads to secure the subfloor. The drywall screws have a lot of thread to hold the drywall itself, but have very little shear strength. In the field between the joists, they are fine.

Chej Fajin

Reviewer

How do you waterproof a subfloor?

If you do not waterproof the subfloor, moisture can make its way under the subfloor and cause mold growth or other damage.
  1. Cut the end of the silicone caulk nozzle at a 45 degree angle using a utility knife.
  2. Install the silicone caulk tube into the caulk gun and push the plunger into the back of the tube.

Lenard Harder

Reviewer

What type of screws to use for subfloor?

The 3/4-inch-thick subfloor takes a 2-inch screw. A thicker subfloor takes a 3-inch screw. Use a heavy-duty drill to drive Phillips head wood screws through the subfloor into the floor joists. Drive the screws approximately 8 inches apart.

Etelvina Flamarique

Supporter

How many screws do I need for a 4x8 subfloor?

Use 8d common nails, spaced 6" apart on edges and 12" apart in the field. 1 1/8"-1 1/4" panels.