Do You Repair A Subfloor From Underneath Or From Above?

How do you replace a small section of a subfloor?

How do you repair a subfloor?

Are walls built on top of subfloor?

It is usually an 8-foot-long, 2×4 piece. Wall studs are nailed vertically to the bottom wall plate and the wall plate itself is nailed (downward) into the subfloor , with nails even extending into the joist. All items except for the underlayment and floor covering rest under and are nailed to the bottom wall plate.

What goes on top of subfloor?

Underlayment: Some types of flooring can be installed directly on top of the subfloor, such as vinyl flooring . Other types need a middle layer, called underlayment, such as laminate,carpet and tile.

How do you install plywood over subfloor?

1. Step 1: Remove Old Flooring. It may seem obvious, but the first step to adding a second layer to your subfloor is to remove the old flooring. ...
2. Step 2: Remove Underlayment. ...
3. Step 3: Decide on Plywood. ...
4. Step 4: Acclimate Plywood. ...
5. Step 5: Install Plywood. ...
6. Step 6: Keep in Mind.

How do I fill the gaps in my subfloor?

1. Move the floorboards. Some people will tell you to stack the floorboards as close to each other as possible when you lay down your subfloor layer. ...
2. Use fillers. ...
3. Use strips of wood or other materials. ...
4. Replace floorboards.

Is it better to use OSB or plywood for subfloor?

This evolved plywood may claim an overall advantage over OSB, since plywood is a stiffer, longer-lasting subfloor option . It will also hold up better under flooring accidents like leaks or flooding, and has greater nail withdrawal strength to hold the nail in under stress.

What do you use to fill gaps in plywood subfloor?

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.

How do you fix the top layer of plywood?

1. Put on work gloves. ...
2. Cut the scored outline with a wood chisel and hammer. ...
3. Mix a batch of water-based wood filler in a one-gallon bucket with a 3-inch-wide putty knife. ...
4. Tilt the bucket to one side. ...
5. Use medium pressure on the putty knife to fill the outer edges of the splintered area.

Can you use wood filler on subfloor?

You can simply use a putty type of wood filler . Or anything to prevent the laminate from dipping. I’ve seen guys use construction adhesive like PL to repair small defects in the subfloor.

What is underneath a subfloor?

Underlayment

The underlayment material is installed below the floor covering and placed on top of a subfloor. Under the visible covering, there is a layer made of soft or foam-like materials with a thickness of between 1/4 – 1/2-inch.

Does framing go on top of subfloor?

If you use a product like DriCore for the subfloor, they even explicitly recommend you frame on top of their subfloor product . They do, however, recommend you screw the framing through the subfloor into the concrete with something like 3′′ Tapcons spaced every 4 ft through the bottom sill of the framing.

Does subfloor go under drywall?

In standard home construction, the contractor installs the subfloor before installing the drywall .

What does the subfloor sit on?

The subfloor is the thick flat surface on which all other layers rest. The subfloor is the bottom-most layer and it rests on the joists . If you have a concrete slab floor, the slab may be considered the subfloor.

What should I put between floor and subfloor?

Flooring underlayment is a thin material that rests between the floor covering above and the subfloor below.

Do I need two layers of subfloor?

Almost no one puts down double-thick subfloor in residential applications (for cost and handling reasons), and both layers need to be fastened to joists . Only thin underlayment can be fastened just to the subfloor.

What do you put between subfloor and underlayment?

Use building paper ! Yep, put down an underlayment of 15-pound felt building paper between a wood subfloor and your hardwood planks, and you can reduce the chance of squeaky floors and control moisture.

Can you put new plywood over old subfloor?

Conclusion. Installing a plywood underlayment over a subfloor is a great way to give your flooring a solid base . It can give you many more years of longevity with your floor. By following the above steps, you can be sure it’s done correctly and won’t warp or crack over time.

Can you lay new subfloor over old subfloor?

Subfloor Options

When laying it over an existing floor, a thinner plywood panel is acceptable ; it should be at least 1/4 inch thick. Particle board can be used, but it’s not as strong as plywood and is extremely susceptible to moisture damage.

Should you glue layers of subfloor?

First layer must be dry prior to laying the second layer. Place a layer of 15-lb felt on top of the subflooring prior to installing second layer. Adhesives should not be used to fasten the two layers together .

Should you nail or screw subfloor?

Ideally, nail down your subfloor using corrosion-resistant nails that will securely hold it in place and last a long time . Screws are a great alternative that you can easily remove, but they are not as sturdy. Screws are superior in terms of reducing floor squeaks, but the installation is slower.

How do you fix soft spots on the floor?

Soft spots in a laminate floor can be caused by an uneven sub-floor or improper installation of flooring underlayment. For quick repairs of soft spots in your laminate floor use an air inflation needle or a syringe (used to blow up sports balls) on a can of spray foam .

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.