By Brandon Jensen, TRA Snow & Sun
There are several factors that one must evaluate when determining if a particular building requires a snow retention system.
The first question you should pose is: “What would happen if snow slides off the roof?”
The second question is: “Do we care?”
When snow slides off of a roofing surface, it can come crashing down or slide off and then piles up on whatever is below the edge of the roof. Snow retention is frequently used to protect landscaping around the perimeter of the building, to protect guttering systems around the edge of the roof, and to keep snow from piling either on a lower roof level or decks, sidewalks and at garage entrances. If nothing below the roof can be damaged by this avalanche of snow and ice, it may be best to let the snow and ice slide off unhindered.
However, what if what is below the roof could be damaged?
Why Snow Retention Is Needed
TRA Snow & Sun offers snow fences, brackets, and clamps to avoid problems like the one shown in this photo. All of TRA's snow retention systems are designed to prevent large sheets of snow or ice from falling off a pitched roof. The systems hold the snow on the roof so it can gradually melt off, preventing damage to people and objects below.
During the winter months, as snow accumulates on your home, gravity will begin to pull it down the slope of your roof. There are many reasons this can be harmful to your home or even dangerous. In worst structural cases, this can lead to damage to costly gutter systems, structural damage to lower roof levels, and even destruction of mature landscaping around the perimeter of a home.
Low-slope roofs with parapet walls naturally keep snow and ice on the roof. On a sloped roof, however, large chunks of snow and ice can slide off as the snow melts. Avalanching snow is probable on roofing systems with a steep enough slope and/or a low coefficient of friction. This is especially dangerous for pedestrians walking below.
Choosing The Right Snow Retention System
There are many types of roofing materials - each has advantages and disadvantages and each should be considered when determining the placement of snow retention on the building.
When considering whether to install a snow retention system on your roof, you may first want to consider what type of roof you have. Will your roof allow snow to slide? Probably. In places with heavy snows, like areas in Utah, it is common for snow to slide off of all types of roof systems, leading to heavy ice and snow build up in gutters, which causes damage over time. If you have a metal, tile, slate or membrane roof with a pitch of 1/12 or greater, snow will definitely slide off and cause problems.
Snow retention systems are available for all types of roofs and come in a variety of options. The specific snow retention equipment recommended for your roof will depend on the type of roof system installed, the pitch of the roof, snow load, sheathing type, how old the building is and budget.