We live on the ocean, which means lots and lots of moisture all of the time. When we built our house, we put pine beadboard up as a ceiling for our wrap-around porch.
Didn't get around to staining it for a year (typical, I must admit) until I stained the rest of the house (all cedar shakes). At that time, it was kinda mildewy, so I cleaned it with a mildew cleaner, pressure-washed it, let it dry for two summer weeks and then stained it with a brush and a high-quality semi-transparent oil-based stain.
Fast forward two years...the porch ceiling is a mildew farm. I have now cleaned it again, with an even more aggressive mildew-cleaner, and for the moment, it looks beautiful.
What to do now?
I hate to start painting it, because it has several pine knots and I have enough of a bleed-through problem indoors with our trim. But I will if that makes the most sense--I've even thought about applying some kind of boat paint or spar varnish??
I could apply oil-based stain again, maybe with more pigment? Would that make any difference?
My goal to try to reduce the maintenance here...frankly, it's a BIG PORCH and spending two days on a ladder painting or applying mildew cleaner over my head causes me to walk funny for several days and also causes me to say rude words quite loudly, which frightens the dogs.
Help!? I can hear those little spores reproducing!