Flat roofing

There are several different roof systems that can be used for flat roofing — 4-ply tar and gravel, SBS modified membrane, EPDM and TPO — each with different applications involved. Insulation is normally installed as part of the roof system, unless the building has been insulated from the inside.

When re-roofing, the existing roof system is taken off and all debris dumped. The steel deck is swept clean, and may have to be patched in a few areas due to redundant pipe openings and similar penetrations.

Insulation

Polyisocyanurate ("Poly ISO") is a UL Class A fire-rated board insulation. It comes in 4x4 or 4x8 sheets in varying thicknesses, depending on the thermal resistance values the building requires. It is normally installed with plates and screws over the vapour barrier on the roof deck, and can be tapered to produce a positive flow of water toward the roof drains.

Fibre board insulation is an engineered wood product made of wood fibres. It is installed over the ISO board insulation, normally with hot asphalt.

SBS modified membrane

The base sheet is a non-woven polyester 100 or 180 g/m² reinforcement sheet, either torch welded onto a protection board or applied with hot asphalt onto the fibre board insulation. Parapet flashings are installed with 3-foot pieces of 180 g/m² modified membrane, torch welded or applied with hot asphalt.

The second layer is a modified plus NP 180 or NP 250 poly cap sheet, most commonly torch applied. Its factory-applied granular surface aids ultraviolet resistance and durability, comes in various colours, and gives excellent puncture resistance and strength against tearing. SBS is an excellent system that will give many years of protection against the elements.

EPDM

EPDM is a single-ply system built on a synthetic rubber compound. It has been on the market for over 40 years and has proven excellent in both wearability and cost. It can be installed loose-laid with a river-wash gravel ballast over the membrane, fully adhered with adhesive, mechanically fastened with screws and plates, or hot mopped with hot asphalt. It comes in various thicknesses, with 45 mil and 60 mil being most popular.

TPO

TPO (thermoplastic polyolefin) is a single-ply system that has become very popular in commercial and industrial roofing. It comes in white, tan or grey, which reflects sunlight and cools the roof rather than drawing heat the way a black roof does, reducing air conditioning costs. It is Cool Roof Rating Council certified and meets ENERGY STAR requirements.

TPO is a cold-applied system that can be mechanically fastened or fully adhered, with seams welded using a hot air welder. It comes in various thicknesses, with 45 mil and 60 mil most popular in the industry.

EPDM and TPO both have fewer seams than modified membrane systems and do not require a hot application. Total system warranties of 10, 15 and 20 years are available. They are hail resistant and withstand winds up to 90 km/h.

Who we work for

We work for general contractors, property managers and residential homeowners. Custom metalwork for flashings is professionally supplied and installed, and emergency service is offered.