Asphalt and Gravel
An aging system
Much less popular, asphalt and gravel roofing could still be seen as a relatively inexpensive alternative to buying for small areas. Considering on the other hand the necessary maintenance and its useful life, the multi-layer roof then becomes one of the least advantageous choices, not only in economic terms but also and especially for its disastrous environmental record. if considering only the buying cost. However, considering necessary maintenance and useful life, the multi-layer roof becomes one of the least attractive choices, not only in economic terms but also and especially for its disastrous environmental record.
A multi-layer roof, as the name suggests, is made up of several layers of felt paper embedded in liquid asphalt.
As for gravel, its role is to slow down the degradation of asphalt layers that occurs with exposure to solar radiation. It also helps to minimize the contractions and expansions of the system undergone by temperature changes.
With the advent of new regulations on reflective roofs, installers of this type of material now offer asphalt with white gravel, sometimes increasing the cost but certainly working in a beneficial way to reduce the temperature variations that the asphalt undergoes.
Note that since January 2015, Montreal’s Rosemont Petite-Patrie and Outremont boroughs have added a clause to their by-laws on roofs, banning the use of this system for new construction, and also for reroofing in Outremont, even with the use of white gravel.
Couvertures Montérégiennes, although equipped for asphalt application, has discontinued offering this system for several years, judging the quality of today’s asphalt too poor for a durable installation protected by a consequent guarantee. However, the equipment can still be used to fix roofing panels on some special applications.
Lifespan: Around 15 years, with the vast majority of insurers no longer offering protection beyond this duration.
Did you know?
Tar ”Refers to an old method which is now prohibited for environmental and public health reasons. However, this material was very durable compared to today’s asphalt