How much does a garage conversion to living space cost in Ottawa?

Converting a garage into living space can be an efficient way to add square footage because the basic shell already exists. As broad perspective only, a full conversion might range from roughly $40,000 to $100,000 or more, depending on garage size, whether you add plumbing and the level of finish. Treat that as perspective, not a quote.

The main cost is bringing the space up to the Ontario Building Code standard for habitable rooms. Garages are built to a different standard than living space, and closing that gap involves several upgrades.

• The floor. Garage slabs are usually uninsulated, slope toward the door and sit lower than the house floor. A raised, insulated subfloor or a levelled, insulated overlay is typical. Ask how each contractor plans to deal with moisture and floor height.
• Insulation and air sealing. Garage walls and ceilings are often uninsulated or lightly insulated. In a climate with winters that regularly reach well below -20°C, the envelope needs real attention. Your designer will confirm what the Code requires for the altered space; renovations fall under Part 11, which requires performance after the alteration to be at least equal to before.
• The door opening. Replacing the overhead door with an insulated exterior wall and windows means framing, sheathing, a weather-resistive barrier, cladding and interior finishing. Matching the house exterior well matters, because an obvious infill can look like an afterthought.
• Heating and electrical. Ask for a heat-loss calculation to decide between extending ductwork and adding a ductless heat pump. New circuits need an ESA notification and are installed by an ESA-licensed electrical contractor.
• Plumbing. A bathroom or kitchenette needs drains, supply and venting, so its cost depends on distance from existing lines.

On permits, the City of Ottawa's list of permit projects includes "adding or removing walls, i.e., creating different room sizes and/or uses", new or enlarged windows and doors, and plumbing alterations. A garage conversion changes use, so plan on a building permit. If you're unsure, contact Building Code Services at buildingpermits@ottawa.ca. Fees are $12.75 per $1,000 of construction value (minimum $117).

Zoning may also have a say. Your zone may set parking requirements, so check your property's zoning before committing to a design. If you need relief from a zoning rule, that's a minor variance application to the Committee of Adjustment.

Finally, garages are valued by many buyers in a snowy city. A local real estate professional can help you weigh lost parking against gained living space. You can browse contractors in the Ottawa Construction Network directory at justynrookcontracting.com and compare itemized quotes.

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Looking for experienced contractors? The Ottawa Construction Network connects homeowners with qualified professionals:

• Luxe Painting and Renovations
• RenoMotion Inc.
• Valcor Construction
• L.L. Renovation
• Grunt Work 4 Grunts

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