Basement & Addition Drywall · Cambridge
Drywall Installation for Basements, Additions and New Units in Cambridge
A basement in a 2005 house in Hespeler and a basement under an 1880s stone house in Galt are the same trade and almost nothing else in common. The permit rules are the one thing they share.
Cambridge's basement work splits with the housing. The subdivisions — north Hespeler, east Galt off Franklin and Can-Amera, the streets filling in toward the 401 — produce bare or builder-finished basements of the ordinary kind. The old towns produce stone and rubble foundations, low joists, damp walls and owners who want to make a legal apartment out of a space that was dug for coal. Additions are spread across both.
Permits in Cambridge
The City's building permits page requires a permit for any structure over 10 square metres (108 square feet) or that includes plumbing, and lists interior structural alterations, adding or removing walls, plumbing or drains, finishing attic space and the creation of additional residential units as permit projects — approved before work begins. Re-boarding an existing finished basement without moving walls or plumbing is finish work. Framing new partitions in a bare basement, adding a bathroom, or creating a unit is a permit first, and Cambridge's wording on walls does not carve out non-structural ones, so the building division gets asked rather than assumed. Inspections of framing, insulation and any fire separation happen before the board covers them.
Subdivision basements
- Drops and bulkheads. Duct trunks, the main drain, the beam, the gas line — each one is framing, board, bead and finishing time, and the count of them drives the price more than the floor area does.
- New framing moves. In a house under a few years old the lumber is still drying and the trusses lift in winter, so corners are detailed to move and the owner is told where touch-ups are likely rather than promised a wall that never cracks.
- Board by room. Moisture-resistant board in bathrooms and laundry, cement board behind tile, ordinary board elsewhere, and everything held off the slab.
- Redoing a first finish. Behind tired panelling or board from the 1990s is framing, insulation and vapour barrier that may be fine or may be the reason the basement smells. We look before deciding whether to re-board or start again; changing insulation is a permit matter.
Old-town basements and additional units
Cambridge permits up to two additional residential units on a lot with a single, semi or townhouse, built with a permit to the Ontario Building Code and with occupancy approved by Building Services. The provincial second-unit guide gives the Code basis: a 30-minute fire separation between units, reducible to 15 minutes with interconnected smoke alarms throughout the house, a basement ceiling of at least 1.95 m over the required floor area, and CO alarms wherever there is a fuel-burning appliance or an attached garage. In a Galt or Preston basement the first question is whether that height exists under the joists, the beam and the ducts at all; the second is moisture, because a stone foundation that weeps cannot have board tight against it. If both clear, the rated ceiling — typically 15.9 mm (5/8 in) Type X for a 30-minute assembly — is built continuous into bulkheads and boxed around every duct and fixture that crosses the joist space, strapped level under joists that never were, and left open for the inspector before it is taped.
Garages and additions
Where new living space shares a wall or ceiling with an attached garage, the Building Code treats a garage that serves only that house as part of the house: no fire-resistance rating is required between them, but an air barrier that is an effective barrier to gas and exhaust fumes is, with a tight-fitting, weatherstripped, self-closing door that does not open into a bedroom. The garage-side board is taped and sealed to work as that barrier. Where an addition meets an old brick house, the two settle differently and the joint between them is detailed with a control joint or a trim line rather than finished across as if it were one wall.
Frequently asked questions
Can my old Galt basement become a legal apartment?
Sometimes. The ceiling height over the required floor area and the moisture in the foundation are the two things that decide it before any drywall is discussed, and the City's permit and Building Services occupancy approval are required either way. We will tell you honestly what the space can and cannot do.
Do I need a permit to re-drywall a basement that is already finished?
If the walls stay where they are and nothing changes in the insulation or plumbing, that is finish work and is not on the City's list. If a wall moves, a bathroom is added or the insulation changes, it is a permit — and Cambridge's list covers adding or removing walls generally, so ask the building division.
Does the wall between my garage and the new room need fire-rated drywall?
Under the Building Code a garage serving only your house does not need a fire-resistance rating between it and the house; it needs an air barrier against exhaust and a self-closing, weatherstripped door. If your drawings call for a rating — a unit above the garage, for instance — the drawings govern.
Serving Cambridge and surrounding areas. Contact us for a no-obligation quote specific to your property.