1

This is a follow up question to this old thread: Replacing hardwood floor in 100 year old house with no subfloor The house has hardwood floors installed directly on floor joists and the floors are very squeaky.

Since the floors are opened now as part of a larger remodel, I wanted to take the opportunity to address squeaking. To the extent that squeaking is caused by the extra flex in the boards in between the joists, below is a proposal to brace the floors by installing "subfloor" in between joists. My question is if I should use a binder layer between existing flooring and the subfloor that will be installed - the layer that is shown in blue. I was talking to one flooring person, and he said "No" since the blue binder would "prevent floor from moving". This seems counterintuitive since in the typical modern installation, subfloor is nailed to the floor joists and then the tongue and grove flooring layer is nailed to the subfloor, thus all layers are connected together transitively through nailing. It seems that the blue "binder" layer in the Proposed solution would be similar.

Since my floors are opened now, I can do a test to see if the Proposed solution addresses the squeaking and see it for myself. My only concern is around long-term implications that may not be apparent on Day 1. Such as, if binder layer does in fact prevent the necessary movement, this may take a season change to manifest itself, etc.

Which binder layer do you think best addresses squeaking and has no long-term negatives?

  1. Construction Glue
  2. Some type of caulk/glue that has some flex to it when is dry to allow for movement.
  3. Foam/rubber/some type of underlayment pushed up against the bottom of subfloor, but not glued.
  4. Nothing. Don't do it, because....

enter image description here

brhans
  • 7,241
  • 3
  • 28
  • 42
ssm
  • 481
  • 2
  • 7
  • 14

5 Answers5

1

The squeaking comes from weight of a person bending the floor.

In any and all cases I would not use glue since it will limit/restrict the normal floor extension and lead to floor deformation (in the hight). If you ever need to repair the floor, the glue will become a problem.

I would simply nail some support using 2x4 between the floor joists, and nailing it into the floor joist while flush mounted to the floor. That would provide enough support for the floor not to bend with persons weight and stop the noise.

Basically you are creating a support grid for the floors at 16x16 or 24x24.

If you decide to nail the floor to the 2x4 use 15-30 angle, so the nails do not come out from flexing.

DIY75
  • 20,686
  • 3
  • 23
  • 47
1

Find the movement from below, and shim it from the underside until it stops squeaking.

Building a new "sub floor" between the joists is only going to make it squeak more, because now you have more places where movement can make wood rub against wood.

Edwin Buck
  • 2,253
  • 2
  • 16
  • 15
0

I would take the advice of your flooring person as I have never encountered or heard of your method being done to alleviate the problem of squeaks in floors.

The squeaks usually result from boards moving against nails. A common solution is to add blocking of 2x material perpendicular to the joists. This may not eliminate all squeaks. However it should reduce the number and it will help stabilize the floor by reducing the movement of the joists laterally. Then you could look for the squeaking boards individually and try to add support to those.

If your problem is that the flooring is too weak and flexes or dips when walked on I would think they need to be replaced, or a new subfloor should be added on top then your choice of finished floor.

RMDman
  • 52,615
  • 3
  • 36
  • 113
0

Easiest is construction glue on the top of the joists and in the grooves of the planks. Typical "panel adhesive" construction glue (most brands have "Nails" in the name) sets to a slightly flexible consistency

Trying to constuct a piecewise subfloor between the joists seems fraught.

Jasen
  • 26,920
  • 1
  • 24
  • 46
-1

What I did to stop bad floor squeaks. Floor was 3/4 clear doug t&g fir sub floor on 2x12 joists 16” OC. 3/8” x 2” white oak top nailed finish floor, 112 year old house. I screwed a 2” steel angle iron between joists with two screews at each DF 4” plank.I screwed the angle iron to the studs. The floor was refinished with sanding and 3 coats of poly. There was almost none or zero improvement in squeaks.

GregR
  • 1