Subfloor Prep for Laminate Hardwod - ?

[mountainsun]

I stripped the carpet and tiles, and the subfloor is in good condition. I plan on taking a belt sander to floor to remove a minimum amount, and just smooth subfloor gently. I had the idea of rolling Kilz on entire subfloor prior to installing laminate wood flooring. My thought was that not only would this keep any odors out, but may help to insulate or seal the seams in subfloor. Has anyone done this, and does this seem like a good idea, or unneccessary waste of time ?

Thanks-

Rick

[Aerowood]

A belt sander would work to even things up abit but I would not get carried away. A dual action or an ordital sander would work alittle better as they will not dig in. Did you check the subfloor in the back and around the perimeter or just what is exposed with the old flooring removed? many people have painted the subfloor for the same reason you are refering to.

[c_lewis77]

I painted my subfloor with kills then outdoor deck paint. I also used a waterproofing membrane between the subfloor and my engineered floor.

[Wabbiteer]

Kilz stain-block is very soft as paints go and needs a top coat to keep from getting softer over time - and might fail/reject any adhesives you're using for the new flooring. Any good exterior acrylic primer for two coats and you're famous if you want to seal odor just toughen up the flooring

And for sanding, a reminder, if you remove much from the seam 'high spots' you've reduced the strength of the wood and any bow or flex may get amplified over the next ten's of years, maybe not at the seam ridge but in the hollows. Give the fasteners 1/4 turn and add some more floor screws? I used a little 3x5" pad sander with 150grit paper to knock the glaze off when I painted the original floor.


A bad aspect of painting the floor is any trapped moisture will want to remain trapped under the paint film - five teaspoons of water absorbed under the C-channel or somesuch will linger longer than if there were no paint, even if there is a plastic underlayment to the new laminate floor. When I painted my old floor I left a 5-inch gap between the painted surface and the shell to better spot leaks and give some surface to wick away moisture.

[samb]

I have to agree with Wabbiteer. After 40 plus years of wooden boat building and restoring I have found that you cannot seal water out of wood 100% no matter how hard you try, but you can certainly seal it in. Allow wood to breathe so it can eliminate moisture. Generally, it does not hurt wood to get wet, but it will be destroyed if it stays wet for any length of time.
On my boats I paint the "wet side" to try to seal out as much water as possible and treat the "dry side" with a breathable oil such as teak oil. The "dry side" must also have good ventilation, or the moisture is effectively sealed into the wood.
Sam