Who should break out an old garage floor in Gloucester?

Gloucester is part of the City of Ottawa, so the same rules apply there as anywhere else in the city. Breaking out and removing an old garage floor is a job a concrete contractor can do, and before anyone signs anything, it is worth knowing what the City, the Code and the locate law require.

The 2024 Ontario Building Code sets a minimum slab thickness of 75 mm for a floor-on-ground such as a garage floor, and requires a compressive strength of at least 32 MPa for the new concrete. We found no City statement on whether replacing an existing garage floor slab needs a building permit. The City lists structural repairs and alterations among projects that do require one, so it is worth asking the City's Building Code Services before the old floor comes out.

On the hardscaping licence: the City's licence covers concrete pads, patios, walkways, steps and similar hard landscaping features on private property. We found no City statement that it covers work inside a garage. Ask the contractor and, if in doubt, the City whether the licence applies to this job.

Locates apply whoever does the work. Under the Ontario Underground Infrastructure Notification System Act, 2012, anyone who digs is an excavator and must submit a locate request before breaking ground. A standard request must be submitted at least five business days before the dig is expected to start, and the locate is free. Ontario Dig Authority relays the request to buried infrastructure owners, who mark their lines. Ask who will submit the locate request and whether any private lines, such as a line running to a garage subpanel, will be marked, because we found no statement on whether private lines are covered by the public locate system.

A few things worth getting in writing before the work starts:

• confirmation of whether a building permit is needed and who will apply for it
• the new slab thickness and the concrete strength specified (32 MPa minimum under the Code)
• whether the granular base will be placed and to what depth (the Code requires at least 100 mm of coarse clean granular material beneath floors-on-ground, though the Code says it need not be installed under slabs in garages, carports or accessory buildings)
• how the old concrete will be disposed of, and whether disposal is included in the price
• the Code requirement that the garage floor slope to drain liquids to the outdoors

We found no published price for a new garage floor slab on its own, so get at least two itemised quotes that separate demolition, disposal, base work and the new pour.

Before you commit, ask the contractor to show you their City of Ottawa hardscaping licence and look them up on the City's published list of licensed contractors to confirm the licence is current.