I am restaining a log home with Wolman Durastain, Semitransparent stain (same stain as on walls now). I know it's not the best stain but it's what's on the house now and I'd like to avoid a complete change.
I power washed the walls and let dry for a few days. It appears there is mildew on logs in several places (this mildew may have appeared during drying (?)). The mildew can be brushed off with rag in places.
The Durastain is supposed to be mildew resistant. Do I need to remove this before restraining? If so what would I use on mildew? Finally is there a good additive you can add to paint to protect against mildew?
The attached picture show the mildew.
Yes, remove the mildew before staining. The stain itself may be mildew resistant, but only once dry and only on the surface. It won't kill existing mildew growth as you apply it. Trapping it underneath will look ugly and could lead to premature failure of your stain.
A sodium percarbonate (oxygenated bleach) cleaner will be the most gentle and clean perfectly well. Apply according to directions & rinse off, then allow to dry. We make a sodium percarb cleaner called CPR, but you can also find them at paint stores & general hardware stores. I'd stay away from bleach, if you can. It will work fine, but is more damaging if not totally diluted and rinsed off.
As far as additives go, there are several on the market. I'd take a trip to your local paint store. They'll have some options. The ones we like best are called Stay Clean I/E and M-1, but there are others that will do the job just fine.
Hope that answers it for now.
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