Our two-part series is on the S-5! Snow Guard Calculator. Step 1 covers exactly why it is so important to engineer your snow guard system. In Step 2, we'll explain how to log on and get started with your calculation!

Snow retention systems go by many names in the industry. Roof snow fences, snow rails, snow stops, snow stopper, snow guards, snow clips, snow bar, and more. Regardless of the phrase, the intended purpose is the same: to reduce the risks associated with rooftop avalanches. By holding back the snow and encouraging it to leave the roof slowly through small amounts or melting, damage to walls and foundations can be reduced.

This is Part Two of a two-part series on qualifying snow retention systems.

In Part 1 of What’s on Your Roof? we discussed how, unfortunately, there aren’t any snow guard police out there patrolling the industry. This creates a two-fold problem: One, that you can’t count on there being building inspectors to check a go-to-market system for structural adequacy; and two, architects and installers of these systems can potentially be sued for personal and property damage from faulty snow retention systems they specify or install.

At S-5!, we don’t recommend installing adhesive-mounted snow guards on metal roofs. From both an economic and design perspective, glued on plastic snow guards typically have low holding strength and are unable to handle harsh weather-related elements. The bond weakens over time and when it fails, the guard can rip away paint and protective roof coatings, potentially leading to corrosion.

When a snow avalanche falls off of a rooftop, it can damage anything in its path! This sudden release of snow can be dramatic—dumping tons of snow in mere seconds. Falling snow forms a temperature-sensitive bond to the surface of a metal roof. Then, when that roof is warmed, whether from the sun or from building heat loss, the bond between the snow bank and roof is broken and a thin film of melt water serves to lubricate the slide.

Metal roofs are a smart decision. But with metal roofs, you must consider the risk of roof top avalanches. A quality snow retention system will help you maintain your roof, avoid personal and property damage, and efficiently and safely allow snow to melt off your structure. But there are a number of methods to mount snow guard systems. What is the best way?

Any snow retention system is a life-safety and property protection application. If the system were to fail, tons of snow could suddenly be released onto anything below, threatening personal safety and property. For this reason, any system should be appropriately engineered to the specifics of the project to ensure that it does not structurally fail. Surprisingly, few (if any) vendors who manufacture provide adequate technical data to do this.