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About 10 years ago now I installed Kahrs half inch oak laminate flooring in my house over a concrete slab.
While doing the install I noted a few spots where the slab was not completely flat resulting in the flooring not laying completely flat. Being lazy I just cut extra foam underlayment to fill the void between the slab and flooring. What I really should have done was pour self-leveling compound and let it cure, but who has time for that crap.
Well fast forward a decade and the foam underlayment has compacted leaving some soft bouncy spots in the floor. I still think my shortcut was worth it because the only real place this has become a problem is the high traffic area of the entry foyer.
Since I'm going to be selling the house I figured I better make these soft bouncy spots better. I laid the entire house without a single break in the flooring so I couldn't just pull up the foyer and level it. So I came up with an Idea. High density expanding foam.
I chose to use Good Stuff window and door because it expands but doesn't exert a bunch of pressure that would bow the floor. It is also foamy and not a crunchy expanding foam to allow doors and windows to expand and contract with the seasons.
I took an old ball inflation needle and cut the tip off just above the side hole and reopened the needle where the cutter crimped it. From there I pushed the good stuff nozzle in and added some tape to make sure it stayed.
I walked on the floor noting the center of the soft bouncy spots and put down a piece of blue painters tape.
I then drilled a 5/64 hole through the floor and put the needle in. As I filled the void I stepped on the floor a few times to disperse the foam better then topped it off. Knocking on the floor in a radius told me the void was full. I want the foam to be quite dense so I filled the void completely. I then let it sit for a moment with the needle still in the hole so whatever is in the nozzle could expand and equalize before pulling it out.
To plug the hole I simply used a toothpick. If you do this make sure you notify everyone in the home and block off the area because you will essentially be creating a punji stick trap. Lol.
I will know tomorrow if it worked which I can't imagine it won't because anything under there is better than an air pocket.
The plan is to pull the toothpick and tape, drill the hole clean and fill with stainable wood putty then a drop of stain to match. If anyone notices that filled and stained 5/64 hole they're just a dick anyway.
While doing the install I noted a few spots where the slab was not completely flat resulting in the flooring not laying completely flat. Being lazy I just cut extra foam underlayment to fill the void between the slab and flooring. What I really should have done was pour self-leveling compound and let it cure, but who has time for that crap.
Well fast forward a decade and the foam underlayment has compacted leaving some soft bouncy spots in the floor. I still think my shortcut was worth it because the only real place this has become a problem is the high traffic area of the entry foyer.
Since I'm going to be selling the house I figured I better make these soft bouncy spots better. I laid the entire house without a single break in the flooring so I couldn't just pull up the foyer and level it. So I came up with an Idea. High density expanding foam.
I chose to use Good Stuff window and door because it expands but doesn't exert a bunch of pressure that would bow the floor. It is also foamy and not a crunchy expanding foam to allow doors and windows to expand and contract with the seasons.
I took an old ball inflation needle and cut the tip off just above the side hole and reopened the needle where the cutter crimped it. From there I pushed the good stuff nozzle in and added some tape to make sure it stayed.
I walked on the floor noting the center of the soft bouncy spots and put down a piece of blue painters tape.
I then drilled a 5/64 hole through the floor and put the needle in. As I filled the void I stepped on the floor a few times to disperse the foam better then topped it off. Knocking on the floor in a radius told me the void was full. I want the foam to be quite dense so I filled the void completely. I then let it sit for a moment with the needle still in the hole so whatever is in the nozzle could expand and equalize before pulling it out.
To plug the hole I simply used a toothpick. If you do this make sure you notify everyone in the home and block off the area because you will essentially be creating a punji stick trap. Lol.
I will know tomorrow if it worked which I can't imagine it won't because anything under there is better than an air pocket.
The plan is to pull the toothpick and tape, drill the hole clean and fill with stainable wood putty then a drop of stain to match. If anyone notices that filled and stained 5/64 hole they're just a dick anyway.
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