MDF or solid wood baseboard for an Ottawa home?

Baseboard material is a choice between the carpenter and the homeowner; we found no Ontario Building Code (O. Reg. 163/24) rule that specifies one over the other for interior trim, and trim is on neither of the City of Ottawa's permit lists.

What decides the choice for your home comes down to a few things worth discussing with your carpenter before ordering material.

Paint finish versus stained finish. MDF takes paint smoothly because it has no grain to telegraph through the finish coat. Solid wood accepts stain and clear finishes in a way MDF does not, so if you want a natural wood look, solid wood is the path.

Moisture exposure. Bathrooms, mudrooms and anywhere the baseboard sits close to a wet floor are worth flagging with your carpenter. MDF can swell if water gets into the bottom edge; solid wood moves differently. Ask your carpenter how they plan to seal the bottom edge and what caulk or gap they recommend at the floor, whatever material you choose.

Profile availability. Wider or more detailed profiles, including heritage-style mouldings that suit older Ottawa homes, are cut in both materials. Your carpenter can tell you what profiles are stocked locally in each and whether a custom profile needs to be milled.

Fastening and finishing. Both materials are nailed or screwed to the wall framing or blocking, then filled and caulked at the top. Ask your carpenter whether the walls need blocking added first, and how they handle inside and outside corners, because the joinery method differs slightly between the two.

Painted built-up profiles, where two or three pieces of moulding are stacked to create a taller baseboard, are done in both materials. If you are matching existing trim in the house, bring a sample piece so the carpenter can match the profile and the material.

Ask your carpenter to specify the material, the profile name or dimensions, and the finish method in writing before any material is ordered.