SNOW RETENTION / SNOW GUARD
A snow guard system mitigates the risk of sudden and unexpected release of snow from the roof, which can lead to damaged roof panels, gutters, light fixtures, walls and foundations, protection of lower roofs or worse, severe injury to people. The idea is to evacuate the snow in a predictable and controlled fashion, as opposed to a sudden release. It may be hard to imagine that an accumulation of those pretty little snowflakes can have enough force to do serious damage to property and person, but that is the reality.
Snow retention has been used for hundreds of years in regions where snow accumulation on roofs is an issue. Technology has now changed from stones and logs to polycarbonates, zinc and aluminum. With the growing trend towards a more environmentally friendly construction industry, metal roofs in the commercial, industrial and residential markets are quickly becoming a choice of architects and roofers. Metal roofs are made from recycled material (steel and aluminum), and their longevity greatly surpasses that of a shingled roof. A metal roof can last upwards of 80 years and their reflective properties equate to lower cooling costs in the summer. With every new metal roof installed, there needs to be a properly designed and engineered snow retention system.
What should I look for?
A properly designed snow guard system needs to take into account many factors, however the most important questions to ask are?
- can the manufacturer provide load tests on the attachment method to the metal roof whether it is a standing seam or not?
- are the manufacturer’s published load tests based on ULTIMATE loads or does the manufacturer provide both the ULTIMATE and WORKING loads?
- would an engineer be willing to stamp the calculations?
There are many questions to ask however these are some of the more important questions that need to be addressed. The following guide will provide an overview of some important aspects of choosing a snow guard or snow retention system.
