We’v e put a water based semi-gloss finish (“Stays Clear†by Behr) on our pine stain grade window trim in the addition, where we’re living now. The addition is pretty tight, and in the cold weather we have here in Colorado there’s some condensation. This has caused the nail holes at the bottom of each window to get a black stain around all my laboriously matched and sanded putty. Ugly. How do I avoid this in the main house? Those (new) windows are ready for finish. If I use an oil-based poly, it will yellow over time and not match. Is this the trade off? What do you think, would it be worth it to lessen the risk of black stains? How big is the color difference likely to be?
The Stays Clear was easy to apply, very forgiving. We have it on our birch doors as well. I figured that since it is suitable for floors as well as trim, it is durable, but it does not seem to be as durable as I’d like for window trim.
Also, I seem to remember that the best way to finish raw wood is to apply a coat of (oil based) varnish, then putty holes, and then put the finish coats on. Is this standard procedure? (Too late for us but may help others).
Thanks!
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Were the nail holes filled prior to you finishing the wood?
Woods favorite carpenter
If the condensation is unavoidable, use stainless steel finish nails.
Did my BIL's house in oak with minwax stain and water based poly. Been about 15 years without any problems. Did you apply at least three coats with the poly? buic
Water-based finishes are by nature more permeable to water vapor than oil-based finishes are. More coats of either offer more resistance, but it still remains that WB is more permeable than OB.
If you’re determined to use WB or simply desire it, then I’d suggest you try laying down a couple/few coats of shellac before applying the WB varnish. I’d also suggest using a “spar” varnish as opposed to an interior rated product. Diamond Varathane is a pretty good one with decent working characteristics.
Shellac is an excellent barrier to water vapor transmission. If you use Zinnser’s SealCoat (dewaxed product) you won’t have to give a second thought to potential adhesion problems from using a common wax-bearing shellac product. Maybe try applying one coat so you can see your color, then do your hole-filling, then apply at least one more generous coat over that. Two would be better yet. Then your WB varnish coats (plural).
Something to bear in mind as regards using WB finishes is that they’re far more susceptible to damage from alcohol or ammonia-bearing compounds. For instance, that means that if you use WB for windows you’ll need to pay special attention while using window cleaners, etc……because allowing drops of that to linger on the finish can soften it (altering the sheen of the finish or worse) and/or actually strip the finish if left long enough.
I’ve used the shellac & WB varnish combo successfully on the interior of many windows. By successfully, I mean that there hasn’t yet been any sign of rusted fasteners under the finish coats after15 years. That being said, I have seen windows that were finished with OB literally stained black from mildew in high humidity environments. This in a bathroom where 3 teenage boys were taking loooooong lingering hot showers lasting an hour or so each…..and showers immediately following one another, more or less. The normally adequate-sized exhaust fan in that bathroom simply couldn’t compete with what had in effect become a steam room.