My ex-husband built a large pergola over our patio with untreated (pine?) wood. He was about to finish it and then we divorced. I got the house, so he refusedto help or share his plan. 2 years later, the wood is that gray color (I think mildew?) and is splitting just a little at the edges. I see a couple boards have black spots on them and I've sanded down into them and it's definitely rotten in just those areas. I was thinkig of using an outdoor mold & mildew solution to clear it off so I can treat the wood with a weather proof sealer. I'll cut out the rotten parts and use wood filler. I'd like to stain it but don't know if paint would give better protection. How would you do this from start to finish? I'm in a humid, sometimes rainy climate (Nashville) so it's hard to find a few days in a row without rain to dry it out. Thanks!