Metal Roof in Lachine

Canadian-style tin, spelled out

For existing buildings, the Lachine page on flat and low-slope roofs gives this list of allowed materials.

• asphalt, fibreglass or real wood shingles
• heat-welded or self-adhesive membranes
• enamelled metal, or metal painted and baked at the factory
• clay, slate, concrete, fibre cement or similar synthetic tiles designed for roofing
• galvanized sheet, laid Canadian-style, pinched or batten seam
• copper
• zinc
• green roof
• glass

Four of the nine lines involve metal. Canadian-style laying, with small panels locked on the diagonal, pinched seams and batten seams are traditional tinsmithing techniques. They are often seen on older buildings. Copper and zinc are often laid with the same techniques.

Enamelled or factory-baked metal covers modern painted sheet, standing seam or ribbed panels. We install it on houses as well as on commercial buildings.

Flat or sloped: where the list lives

The list above appears in the City's flat and low-slope roof procedure. The sloped roof procedure for Lachine publishes no materials list. It requires a permit to replace the covering or change the structure, nothing more.

The page does not say whether the flat roof list also applies to sloped roofs. We have the product confirmed at the Lachine permit counter, 1800 boulevard Saint-Joseph, before ordering the metal.

A new building

For a new building with a flat roof, the list disappears. The City requires a material with a solar reflectance index (SRI) of at least 78, certified by the manufacturer or a professional, a green roof or a combination of both. Metal on the flat roof of a new building must therefore be very light. The part of the roof taken up by mechanical equipment or a terrace is exempt.

What the permit requires

For a sloped roof, the City asks for:

• the quote or a cost estimate grid, taxes included
• the certificate of location
• the data sheet for the planned materials, showing the SRI
• any other document useful to the review

For a flat roof, it adds a structural plan approved by a professional when the law requires one. The minimum is $491.70 for a commercial, industrial, institutional or mixed-use building. Extra fees may apply to a building or area with heritage value.

Our detailed written quote goes into the file. It names the laying technique, the metal, its thickness and its finish.

Repairing old tin

Repairing or maintaining the covering requires no permit in Lachine. Touching the insulation or the structure does, even for a repair. An old Canadian-style tin roof can often be repaired piece by piece. We come to see the roof before pricing it. We then tell you whether a repair is enough.

Frequently asked questions