Which would be better to use for flat door panels on a painted bathroom vanity – MDF, plywood, or solid wood? -deLancey
While all three make excellent materials for painted cabinetry, on a bathroom vanity I would use a close-grained, hardwood plywood (like birch plywood) for the door panels, cabinet sides, shelves, and tall drawers; and a close-grained, solid hardwood (such as birch, maple, or poplar) for the door frames, small drawers, and cabinet face frame.
MDF (medium density fiberboard) is fine for most painted cabinetry, but it won’t hold up as well to the high humidity and moisture in a bathroom as plywood. Solid wood shrinks and expands in width as the humidity changes, which could cause the paint line to crack over time where the panel meets the frame in a moist bathroom.
Regardless of which material you choose for your vanity, be sure you have a properly sized bathroom exhaust fan, that’s vented to the outside, to remove moisture from the bathroom; and run the fan while showering or bathing and for 15-20 minutes afterward.
Good luck with your project,