Again-Knotty Pine Covering ideas
I may be better off switching to drywall, but I'm interested in hearing from you. Has anyone done this using a fabric undercover? Caulking?
I used cotton muslin, which comes in really wide widths so a wall can be covered with a single piece of fabric. I found wide width muslin at a number of different fabric stores. I used an electric staple gun (my wood was soft enough, but you might need an air powered gun), and stapled across the top first, then alternated from the center of the bottom to the center of the sides, pulling/stretching the fabric to make it smooth and stapling towards the corners. I then put trim moldings over the staples.
I was told that the muslin would be a paintable surface, but it looked to me like the paint would seap through, so I put a paintable paper over the muslin. I used regular old wheat paste, and lots of it. I found it was important not to press to hard or over and over - because this cause the paste to be pushed through to the back of the muslin.
And then I painted with an oil based interior paint. I tried a water based paint at first, but this seemed to loosen the wallpaper. I completed the project last week, so I can't give you info about how it holds up over time. But that's my story so far.
From what you posted, you could calk the joints, have a bucket of water and a rag to clean up with. Before calking sand all the wood lightly(for adhesion)Prime the wood with a quality primer, tell your paint store what you are doing. Cut the tube of calk at a slight angle, about 1/8 inch bead, calk one joint at a time(the faster you get, the more joints you can apply the calk before wiping) and use a wet finger to smooth, remove excess calking with the rag. your fingers will get sore, you can use the rag wrapped around your finger, but will not get the best results. After the calk dries, paint.