Torch-On Roofing System

Most flat roofs in Canada are waterproofed with a three or four-ply built-up membrane of asphalt and felt commonly referred to as tar and gravel. In this case the waterproof layer is placed on top of the insulation where it is exposed to the full effects of climatic variations and becomes a trap for vapor movement. It is also a very rigid system and is likely to crack in the event of structural movement, especially at low temperatures.

A new process called "Torch-On" roofing is now widely accepted as the best replacement for tar and gravel roof systems. Torch-on is a flexible, rubberized asphalt membrane that is applied using a propane torch. The waterproof membrane is placed below the insulating layer so that it is free from harsh climatic variations. Thus it serves the dual purpose of being the waterproofing membrane as well as the vapor barrier.

Torch-on is much lighter and is more flexible and durable than tar and gravel. It comes in a variety of colors, and it can be applied to frost free decks in temperatures as cold as –18 degrees Celsius (not that you are likely to find a crew willing to work in that cold a temperature). Customers agree that torch-on is cleaner, faster and much more attractive than traditional tar and gravel.