Since no roofing system is suitable for all buildings and all needs, it is advisable to hire an expert to evaluate all the issues. The list below summarizes the major recognized systems available and proven in Quebec.

See also below our COMPARATIVE TABLE of major conventional flat roof systems.
 
  • TPO (thermoplastic polyolefin)TPO seaming with welding robot

    Typically a white membrane, delivered in 5 to 12 feet (3.66 meters) wide rolls and polyester reinforced, which allows it to be mechanically secured to the roof at a low cost. Durable, attractive and very reflective, it is more and more popular for basin-type roofs and very low slope roofs. Its junctions are welded with very hot air.
    Learn more
     
  • SBS modified bitumenMelting of elastomer layers

    Bitumen membrane modified with polymers to improve its properties. Reliable, attractive and very popular in Canada. The granulated finish available in a wide color palette serves to protect bitumen against UV rays. Installed in two layers which are fused with torches, the first layer is glued or mechanically fixed to the roof.
    Learn more
     
  • EPDM (synthetic rubber)EPDM membrane gluing

    Black or white membrane known for its unmatched durability in the industry. However, glued joints require great care to last as long as the membrane itself. The white version must be completely glued, while the black can also be ballasted. The black reinforced version can be either mechanically fixed or glued.
    Learn more
     
  • Asphalt and gravel (built-up roof)

    Asphalt and gravel (built-up roof)

    Conventional coating consisting of multiple layers of roof felts laminated together with bitumen. A final layer of gravel is spread on the surface to protect the bitumen from the sun, sudden temperature changes and hail impacts. This system is now seldom used on large surfaces and is losing popularity since some municipal by-laws even prohibit its installation.
    Learn more

  • PVC (Polyvinyl chloride)PVC membrane

    Membrane with thermoplastic properties very similar to the TPO membrane. Aesthetic and durable, despite its poor environmental reputation. Its junctions are welded in the same way as the TPO membrane.
     
  • Coatings and other flat roofing systems

    Polymers, bitumen, silicone, acrylic, liquid rubber, fiberglass, polyurea, etc. Many products are offered on the market but very few are thoroughly tested and standardized by the industry. Few specialized labor and installation standards brings the risk of losing local expertise by using a method which is too marginal.



 

Comparative table of major flat roofing options
 

This table shows an overall view presented for information purposes only. Endless variables can substantially modify the information it contains, use with caution and discernment.
 

Roofing
Type

Average product
life (1)

Annual
cost (2)

Purchase
price (2)

Reliability
(3)

Versatility
(4)

Reflectivity
(5)

Environmentally
friendly (6)

TPO
Membrane

good

very
low

low

average

good

very
good

very
 good

Modified
Bitumen

good

average

high

reliable

very
good

average

low

EPDM
Membrane 

good
(1)

low

high

average

good

good

good

Asphalt
and Gravel

low

high

low

very
reliable

low

low

very
low

PVC
Membrane

good

low

average

average

good

very
good

low

 

 
  1. Product life is not only based on the sustainability of the material itself but also on its seams, for example EPDM membrane itself is very durable but its glued joints last often less than with other systems.
  2. Cost classification is based on a small area (less than 200 square meters or 2000 square feet). Beyond that, mechanically attached systems become more and more economical, even compared to ballasted systems.
  3. Reliability includes resistance to fire, impacts, punctures, tears and natural elements.
  4. Versatility considers ease of installation in all circumstances and the ease of modification and repair.
  5. Reflectivity depends largely on the effectiveness of the system to self-clean.
  6. Classification of the ecological value of a system is not only based on its recyclability since some materials are recyclable but not recycled, such as elastomer in Quebec. This value is greatly affected by sustainability but also by the amount of energy required in the material's life cycle.