When installing snow guards, always refer to the manufacturer’s instructions. For this reason, the snow bank’s downslope extremity is the best place to interface with snow guards.Īdditionally, slope is a critical component in the engineering/design of snow retention because steep slopes combined with long panel lengths are two of the factors that help determine if multiple rows of snow retention are needed. This results with the greatest compressive strength of the snow bank at its base (adjacent to the roof surface) and at its downslope (eave) end. The compressive strength of snow increases as it compacts from its own weight, increasing its density. All snow guard devices rely upon the compressive strength of a bank of snow to resist its downward migration. In general, snow accumulates on a roof with greater concentration near the eaves and valleys due to wind scouring. The majority of the snow load is carried on the bottom half of the roof due to heat loss, wind, sun exposure and gravity.Įxact placement of snow guards is a mixture of art and science. If your overhang is 1′ then the first row of snow guard should be at approximately 2.5′ from the eave) as this is most likely where heat will escape due to poor insulation, causing ice damming and snow build up. Current code suggests 18″ inside the building envelope (ex. Generally speaking, if installing one row and using a continuous rail-type system, your snow retention would be installed approximately 1 to 2 feet from the eave. And, depending on the system, snow guards can be placed in a single line, or in multiple rows. Snow guards should always be placed at the lower half of the roof plane. Lesser quality paint finishes on the snow guards will fade more rapidly than the roof, producing a very unsightly mismatch within a few years. In order to color match the roof material, it is recommended that the type of paint or powder coating is equivalent to the roof material in terms of fade and chalk characteristics. Snow guards are considered a life/safety product, and therefore should have the service life and durability equivalent to the roof itself.īecause metal roofs have exhibited service lives of more than 60 years in documented field studies by the Metal Construction Association (MCA), this requirement should rule out the use of plastics (polycarbonates) as they do not measure up to such a service life in outdoor exposure. The panel type and material, roof size, local snow loads and aesthetics are some other issues to consider.” Either type can work-continuous rail or discontinuous cleat-type systems-provided that either is appropriately tested, correctly installed and proven by engineered calculation to resist the in-service loads presented on a site-specific basis. Continuous snow guards can be made up of one or multiple cross-members.Ĭhoosing the right type of snow guard is a decision largely based on aesthetic and personal preference. These can be single or multi components: brackets or seam clamps that are attached to the roof, and cross-members that are anchored to the brackets or clamps that restrain the sliding snow. Snow cleats or pad style snow guards (like our Snow Yeti) are normally used in a redundant fashion, relying on the “bridging” of a snowpack to span between adjacent devices to limit snow build up.Ĭontinuous snow guards are otherwise known as rail type snow guards, snow fence, snow rail or pipe-style snow guard. There are discontinuous snow guards, and continuous snow guards. Snow guards come in a variety of shapes and sizes. Snow retention systems reduce the risk of sudden rooftop avalanches and mitigate the hazards present in the area below the eaves. The collection of snow on a roof can produce significant sliding forces, which can cause the snow to fall suddenly. The buildup of snow and ice on a pitched metal roof causes challenges in many areas around the country. What Type to use, How and Where to install them correctly
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