Torch-On Flat Roofing – Commercial & Residential

Alliance One Constructions Limited installs two-ply torch-on (SBS modified bitumen) flat roofing for commercial buildings and private homes across Alberta and British Columbia. Every roof is installed by trained crews to a watertight, code-compliant standard built for Canadian weather.

Torch-on flat roofing membrane being applied on a commercial roof in Alberta

What is torch-on flat roofing?

Torch-on roofing — also called SBS modified bitumen — is a multi-layer membrane system heat-welded directly onto the roof deck. A base sheet is fastened or adhered first, then a cap sheet is torch-applied over it so the two layers fuse into one continuous waterproof surface.

Because the laps are melted together rather than taped or glued, a properly installed torch-on roof copes with freeze-thaw cycles, ponding water and heavy snow loads far better than most single-ply alternatives. That is why it remains the standard choice for flat and low-slope roofs in Edmonton and across the Lower Mainland.

Commercial torch-on roofing

Flat roofs carry the majority of the risk on a commercial building. A failed membrane means water in the ceiling, damaged stock and interrupted trading. We install and replace torch-on systems on:

Retail units, plazas and strip malls
Warehouses, workshops and light-industrial units
Offices and mixed-use buildings
Apartment blocks, townhouse complexes and strata properties
Restaurants, clinics and community buildings

We work around your operating hours wherever possible, keep the site tidy and staged so only one section is open at a time, and protect entrances and parking areas throughout.

Residential torch-on flat roofing

Flat and low-slope areas on a house are where leaks usually begin. We install torch-on membrane on:

Flat-roofed homes and modern extensions
Garages, carports and workshops
Roof decks, balconies and walk-on surfaces
Dormers, porches and back additions
Parapet walls and box gutters

Our installation process

Inspection and quote. We measure the roof, check the deck, drainage and flashings, and give you a written, itemised price.
Tear-off and preparation. Old membrane is stripped, the deck is inspected, and any soft or rotten sections are replaced before anything new goes down.
Vapour barrier and insulation. Fitted where the build-up calls for it, to control condensation and improve thermal performance.
Base sheet. Mechanically fastened or adhered to give the cap sheet a sound, even substrate.
Torch-applied cap sheet. Heat-welded with fully sealed laps to form one continuous waterproof layer.
Flashings and penetrations. Drains, vents, curbs, skylights and parapets are detailed and sealed — this is where most flat roofs actually fail.
Final inspection and clean-up. We walk the roof with you, check every detail and leave the site clean.

Why choose Alliance One Constructions

Crews trained in torch-applied membrane systems and hot-work safety
Fully insured workmanship, backed by a written guarantee
Clear written quotes with no surprise extras
Offices in both Surrey, BC and Edmonton, AB — genuine local coverage
One contractor for the roof, the flashings and any related repair work

Areas we serve

British Columbia: Surrey, White Rock, Delta, Langley, Richmond, Burnaby, New Westminster and the wider Lower Mainland.

Alberta: Edmonton, St. Albert, Sherwood Park, Spruce Grove, Leduc and surrounding communities.

Get a free flat roofing quote

Tell us the size and condition of your roof and we will give you a straight answer on what it needs and what it will cost.

Request a free quote
Toll Free: +1 877-634-1871

Alberta: +1 780-388-0429 | British Columbia: +1 604-445-0113