Building a basement shop

During a home-improvement question-and-answer forum I hosted for three days at the Canadian Home Workshop Show, I was surprised to hear that three-quarters of all the queries had something to do with basements. Canadians are hungry to learn about finishing basements properly, and many questions were specifically focused on finishing walls and floors for workshop duty.

Turning an unfinished Canadian basement into a comfortable workshop space is really about the same three things that apply to any basement-finishing campaign: insulating walls, finishing floors and boosting sound resistance. Doing this work right involves specific techniques that aren’t always obvious and not always typical. Basements can go bad in big ways if you’re not diligent.

The non-negotiable prerequisite for finishing any basement is that it has proven to be completely dry year-round for several years. But even still, basements are holes in the ground, so some kind of water intrusion is always a possibility, regardless of the track record of your home. That’s one reason I like foam-based systems for insulating walls.

Instead of wood or metal wall studs filled with batt insulation, sheets of extruded polystyrene foam work much better below ground. Besides being easier to install than stud frames with batt insulation, extruded poly foam and wood battens are much less susceptible to water damage– in both liquid and vapour form. If batt-insulated stud-frame walls get wet, for instance, it’s like having a sopping beach towel stuffed into a plastic bag inside your walls. Mould, mildew and decay are sure to develop because the soggy wall cavities remain wet for a long time. The right kind of foam, on the other hand, doesn’t absorb water. Foam also delivers more effective insulation properties because it creates an unbroken layer of insulation that’s not diminished by drafts through wall cavities.