Priming Copper-Green Wood Preservative
I am using doug fir for the beams in a patio cover that is being built in northern CA. The beams will be primed with oil-based primer, and then a latex top coat. First, it was recommended that I treat the cut ends and notches with Copper-Green Wood Preservative for added protection. Then, afer talking to a Green’s representative, he recommended that I also put a skim coat of the Copper-Green onto the face of all beams and rafters for added protection. (The product label clearly states that one coat can be applied to materials to be finished with an oil or alkyd paint, and the Green’s representative confirmed this.) Thinking that anything that I can do to extend the life by even a year or two would be worth the extra effort, I did as was recommended. Then I visited Benjamin Moore to pick-up a premium primer, and when I mentioned the skim coat of the Copper-Green Wood Preservative (which is solvent-based), the sales person told me to get out the belt sander and strip off the wood preservative before applying the alkyd penetrating primer. And a follow-up call to the Benjamin Moore contractor hotline did not offer any meaningful advice as the rep said that he was not familiar with the Copper-Green product. My question is…Does anyone know if an alkyd-based primer can be applied over the Copper-Green wood preservative with good adhesion? Or would it be best to strip off the Copper-Green wood preservative?
Replies
I treated all my rafter tails and eave shiplap with Copper Napthalate (25%)... I didn't read up on which primer/paint to use though. I just made sure it was dry, wiped off any exess and primed with Kilz and painted with a Behr Exterior Gloss White. There are a couple places that are a little mint green tinged, but you have to look close for that. It's been about 7 years now and no adhesion problems so far.
Kilz?
I find this to be an interesting recommendation, as the original oil based Kilz is not rated for exterior use. Kilz does make Kilz Complete which is an interior/exterior rated oil based primer. I bet, nine times out of ten, if you go to the store and say you want Kilz, you get the original Kilz..
Ummm... I forgot about all the differences in Kilz! I did not use oil based - I used Latex!
The wood was very dry though, and the green had been allowed to dry (soak in) for awhile as well. Like a couplw weeks probably.