How to plan a basement renovation

Finishing a basement is usually the cheapest way, per square foot, to add usable space to an Ontario home. It is also the project with the most hidden conditions, which is why the planning order matters so much.

Solve water before anything else

Framing and drywall over a damp foundation is money spent twice. Watch the space through a heavy rain and a spring thaw. Look for efflorescence, staining, musty smell, and floor cracks. If there is any doubt, price the drainage work first and the finishes second.

Confirm the constraints

• Ceiling height after framing, flooring, and any ductwork changes
• Beam and post locations, which dictate the layout
• Existing drain elevation, which dictates where a bathroom can go
• Egress window requirements for any bedroom
• Panel capacity for new circuits

Expect a permit

Basement development normally requires a permit covering framing, insulation, fire separation, egress, plumbing, and electrical. If you are considering a secondary suite, zoning rules apply as well, and those vary significantly between municipalities.

Budget the unglamorous items

Insulation, vapour control, fire separation, HVAC extensions, and moisture management consume a large share of a basement budget without producing anything a visitor will notice. Plan for them, then decide what is left for finishes.