How do snow guards work?

Metal roof snow guards hold snow and ice on a roof until it can melt off safely.


Snow Rails Holding Snow

Snow guards, also known as snow retention, snow stops, and snow brackets, are devices installed on sloped roofs to prevent the unexpected release of snow and ice, mitigating potential property damage or personal injury. By placing the snow brakes across the entire roof, it will hold the snow and ice in place until it melts or sheds the roof in smaller amounts.

What are the most popular types of Snow Guards for Metal Roofs?


SnoBar on a Roof

This type of snow fence system will be placed in a straight line, sometimes in several sequences going up the roof, to prevent snow avalanches on sloped metal roofs.


Individual Pad-Style Snow Guards

Snojax on a canopy

These types of snow catchers should always be installed in staggered formations across the entire roof to act as fingers to grip the snow and ice. These types of snow guards can be mounted with screws or adhesive. Never run individual snow guards in a straight line, or it will defeat their purpose and waste money through misapplication.


Clamp On Snow Guards

SnoCleat RCT

Clamp-on snow guards are an excellent option for buildings with a floating standing seam metal roof. This type of snow guard does not penetrate the roof but is mechanically attached to the seam, which provides adequate holding strength. The main advantage of this product is that it can be installed at any time of year.

These snow guards typically clamp onto a metal roof's standing seam without penetration, and there is no need for glue or sealants during installation. Furthermore, some clamp-on snow guard products, like the SnoCleat, include unique features like a swivel bracket for angle adjustment in hips and converging valleys.


Choose the Right Attachment Method


PolyCarbonate Snow Guards

Polycarbonate snow retention can typically be attached to any type of metal roof using adhesive. Polycarbonate snow guards mounted with SureBond SB-190 is the only time-proven option for gluing guards down. A reputable company will publicly publish their test results for this type of application. Many people prefer this method because the snow guard will not cause damage to the roof panel if it comes off. If the system has become overloaded, an adhesive-mounted snow guard can be easily reinstalled in the same location on the roof.


Screw Down Installation:

Screw Down SNow Guards

Mechanically attached snow guards work best on roofs with exposed fasteners. The snow guards should never be stitched to the panel itself; they must be attached to at least a 1-inch substrate for wood. If your building has steel purlins, the snow guards should be attached to them with at least two self-drilling screws. The screws should always have a rubber neoprene washer installed under the head. Mounting snow guards with screws is the strongest method if there is adequate substrate under the panels for attachment. The roof system must be able to accept roof penetration without voiding any warranties.


Clamp on Attachment:

Clamp On Snow Rail

Snow guards must be crimped to the seam with a clamp on a concealed fastener roof. This type of roof covering is commonly called a standing seam metal roof. The clamp method is recommended to avoid unnecessary roof penetration. It is important to note that if there is not an adequate amount of snow retention used, seam damage may occur if the system is overloaded.


Follow Manufacturer's Spacing and Installation Instructions

Snow Guard Spacing Example
Before beginning the installation, it's essential to read the snow guard manufacturer's spacing and installation instructions. This includes specific information about the recommended adhesive to buy along with time and temperature requirements, the best screws to use, following the suggested placement for the snow guards, and any other tips that will help to achieve a successful snow retention installation.

Snow Guard Buying Tips:

  • Use high-quality metal roof silicone to seal any roof penetration from screws to avoid roof leaks.

  • Make sure selling snow retention systems for metal roofing is the vendor's primary business. There are many plastic molders selling cheap, untested knock-off plastic snow guards. Buyer Beware!