Yes, I agree with the last 2 posts-JonMon and Mark. You WILL have to strip whatever is on your deck currently. My goal in life is to work with wood products that don't have to ever be stripped. We are still stripping the exterior of our clapboard house that has 130 years of peeling paint build up. That is how we came to learn about Allback Paint. Linseed paint has been used for hundreds of years. If you ever tour Mt Vernon, President George Washington used it. However, the new products are greatly improved by purification process. Linseed products protects and nourishes the wood and leaves it breathable so there is never trapped moisture and a plastic coat to peel. The draw back is the slower dry time. There are no chemical accelerators. This fact makes the product "GREEN" for the environment. Hot dry days are a perfect time for painting Boiled Linseed. To find out more about Purified Boiled Linseed try the link posted or call Soren or Collete at Viking Sales. They have been most helpful to me. Be sure to ask them if your climate will allow the Boiled Linseed products to cure properly. I live in the mid-central states. We had 30 days of 100 degree weather this year. I am still researching Floor Shield USA and Lifeline Endure at 1-800-548-3554. If I cannot find a longer lasting product that doesn't need stripping to re-coat than the AllBack products, I will definitely be using the Linseed Varnish mentioned in the link. Strip a deck once and you're desperate to never do it again. Here is a link that might be useful: Silent Paint Remover and Allback Paint

Thanks for all the great suggestions! Update: We removed the board from the wall and did a couple of experiments once we could see better what we were dealing with. There didn't appear to be any water damage behind the tile on the wall, just to the drywall and wood right near where the shower meets the wall. First, we ran water (without someone standing in the shower) and didn't see any water seeping out. Second, someone stood in the shower. When water splashed off the person and ran near the corner we could see a tiny trickle of water between the metal and the wall. Once everything is dry again we will re-caulk that area (DH is good at caulking, thank goodness!). Once that is dry we can re-test. Hopefully, that will correct the problem. If not, we will call someone out to fix the hairline crack, but we are fairly sure (as other posters have stated) that it is not the root of the problem. I posted this in this forum and the plumbing forum because it wasn't obvious to us if this was, indeed, a small repair (which it appears to be) or if it could be an issue with plumbing behind the wall that we couldn't see. I have been a member of these forums for several years (particularly kitchen and home decorating) and see people post questions in multiple forums quite a bit. Especially if the issue is not straight forward.

You shouldn't need to replace the drywall. If you have ripped off the paper facing of the drywall, just apply some Gardz to that area and then patch it and paint as normal.

Oh Lordy! There’s probably a hundred shades of white paint. Your best option is see if you can scrape a paint chip off the sill and take it to your local paint store. They may be able to match it close enough. The other option is to go to a paint store and find the paint color cards. Pick as many as you can, bring them home and see which ones match as close as possible. Once you pick the right color, go back to the paint store and buy a quart of that color. You should be able to buy a quart of primer there too. Also buy fine grit sandpaper and a good brush for applying water-base latex. Any brand of paint will do. However, if the original paint is oil base, then you will have more work to do. You can’t apply water base paint over oil base paint without first sanding the entire sill and applying a primer.