Industry experts share their top tips and tricks
• If your project is in snow country and you plan on installing rooftop solar arrays, it would be advantageous to consider the placement of your snow retention system in advance. Often, snow rails are an afterthought. It’s essential to plan the PV array orientation in concert with the snow retention system to ensure there is enough room for the snow guard placement. Plan both simultaneously so that local building codes are met and both systems function correctly.
• It’s important to understand the design load and torque values for the clamps that anchor the snow retention system to the roof. The design load resistance of the system is based on real-life test results conducted on the type of roof that is on your project. Overtighten, and the roof can become damaged, or the fasteners can strip out. Under-tighten and a moderate snow load may tear the snow rails from the roof, resulting in roof damage and leaks into the interior.
• Read and understand the manufacturer’s installation instructions. If there’s something that you don’t understand, call the manufacturer for clarification—don’t guess.
• Never underestimate the weight and power of snow, especially when wet. Serious injuries have been recorded for years when systems are not properly specified or installed. Only trained or certified roofing specialists should install new snow guard systems.
• One important consideration when planning snow management for a post-frame structure is the building’s geographical location. Will a snowshoe work? Or does it need an engineered system based on the average annual snowfall/temperature/elevation?
• Just as important is the roof pitch and snowshoe placement.
• When installing chemically adhered snow guards, keep an eye on the day’s temperature. Application temperatures should be above 40 degrees.
• Apply adhesive snow guards to a clean, dry surface for the best adhesion (clean with 91% isopropyl rubbing alcohol prior to application).
• Plan for sufficient overhangs to prevent leaks around doors and windows.
• Ensure the roof runoff is directed away from all door and window openings.
• Install rain diverters above first floor doors on two-story structures or elevations with high gable ends.
• Rain diverters are a great option to prevent leaks on in-swing doors.
• When planning a snow/rain management system, make sure you know the substrate type (whether its 2X material, plywood, etc.). Knowing the substrate and choosing the proper fasteners for the particular substrate helps ensure you will attain the strongest possible system.
• Check for engineering. Buying your snow guards from a manufacturer that tested their products in the specific substrate being used on your job will facilitate the best performing system.
• When installing mounting brackets, it is ideal to fill all the mounting holes with fasteners. If filling all holes is not possible, the upslope holes must be filled.
• Also, when installing mounts, fastening to the roof panel alone is not recommended. These mounts must be attached with mechanical fasteners to the roof substrate.
• Care needs to be taken with snow retention on post-frame buildings. The safety of people and property is the biggest concern. Where applicable, snow retention should be used where a snow or ice “slide” can occur, resulting in injury or damage.
• Factors such as where the building is located, which way it is oriented, whether it is windswept, and the direction of the prevailing wind should all be taken into consideration.
• For rain management, always use 7″ commercial gutters with downspouts and slash guards to move the water away from the structure.
• When installing snow retention devices, make sure they are spaced properly and according to the manufacturer’s recommendations.
• One of the most important things to consider when planning for a snow management system is the vendor’s proof of engineering. Snow guard systems are science-based, so manufacturers should be able to provide the data behind their products.
• Proof of testing is also essential for the same reason as stated above.
• A tip for choosing the right snow guards for each specific roof is to make sure the product is compatible with the roof in terms of longevity, method of attachment, and weatherability. A metal roof typically has a 40- to 80-year service life. The snow management system should, too.
• Ask to see the warranty before you buy and read the fine print!
• Consulting with a reputable snow guard manufacturer to determine the best system options prevents numerous pitfalls down the road.
• Once a decision has been made regarding the style of snow guards to be used, always have the manufacturer provide a project-specific layout. This ensures that the load is properly distributed and the system can effectively manage the snow load for the life of the roof.
• Log the local ground snow load, roof pitch, run, and width of each roof area. This information must be accurate in order to determine the correct layout for the project.
• A discussion about snow retention on metal roofs should be done early in the construction planning of the metal roof. Many customers with new metal roof systems are completely unaware of the dangers of sliding snow and ice until after they have suffered gutter and vent pipe damage. FN
