Preparing pine wainscoting for a bathroom

Do the cut ends, as well. Moisture will condense, run down and collect on bottom of boards as it does on doors and woodwork. It can wick into the end grain if not sealed up. Alkyd is my choice for woodwork, kitchens and baths, as I believe is is less permeable than latex. Also easier to sand out globbies and brush marks. Could be wrong. Paintable caulk might not be a bad idea.

I second Norminn's comments. Based on talks with contractors and paint reps: Primer is a required first coat over raw wood. Paint seals out water vapor and water 85% better than primer. End grain takes in water many times more readily than other wood surfaces. TB

Prime *both* sides to prevent warping and then paint the side facing away from the wall. That's it.

Dimitri

Always use a primer. Since it is in a moist environment, prime and paint the back also before you install it. Then just go back and touch up any marks from cutting and nailing.