Double Fold Steel Snow Guards

Double Folded Snow Retention System

Price Versus Function

Folded Over 29 Gauge Snow Rail Advantages:

Snow Retention System Cost:

The folded over metal snow rails are a low-cost snow guard option for screw-down metal roofs and can be effective on low-pitched metal roofing.

Snow Rail Color Choices:

Many stock colors are available for this continuous snow rail system.

Better Than Not Having Snow Guard Protection:

Installing this type of snow retention is better than installing nothing, but there may be a risk of potential roof leaks over time.

Folded Over 29 Gauge Snow Guard Disadvantages:

Limited Applications on Metal Roofs:

The folded metal snow rails can only be screwed down and are not suitable for installation on floating standing seam roofing. Installers should never penetrate a standing seam metal roof with screws or fasteners. Typically installed on a clip system, a concealed fastener roof is attached to metal roof clips fastened to a wood deck. Standing Seam panels typically float on these clips. Screwing through the roof will usually interfere with the thermal expansion associated with these types of roofs. This product may be unsuitable for standing seam roof applications. Never install a screw-down snow retention system on a concealed fastener metal roof. The picture below shows a misapplication of this system installed on a standing seam metal roof.

Attachment Point of the Folded Snow Guards:

Most metal panel manufacturers recommend that screws or fasteners should never run through the high ribs. Sometimes, installers attach these folded pieces of metal only into the high ribs without hitting a purlin or structural support. It is unacceptable to fasten any screw-down type of snow retention system to the seam of a metal roof. There is no way to attach this snow retention system to the flat portion of the metal roof, where the snow and ice move because it sits on the high ribs. Installers of snow rails must connect them through every rib to a purlin or structural support below, but this does not always happen in the field. The snow and ice can rip the folded pieces of metal right off the roof if the screws are stitched just to the high rib. If this happens, roof leaks can cause expensive damage inside the structure. Notice on the picture below that the rail is fastened to every other seam rather than every seam as usually recommended. It is common to see this type of misapplication with this kind of system.

Sustainability of the Snow Guard System:

The folded-over metal snow rail system may be prone to leaks in the long run. Most exposed metal roofing manufacturers do not recommend screwing anything on the high ribs because when the panels expand and contract, the holes will oblong around the screw points. Installing any snow rail system to the high ribs could result in unexpected roof leaks and extensive interior damage. All screw-mounted snow guards should attach to the flat portion of the metal roof with the screws attached to the purlins or structural support below.

Snow and Ice May Still Slide Off the Roof:

Since no flat surface holds the snow and ice, it can still come off the roof in large chunks. When the snow and ice start to melt, the snow and ice may ramp up and over the bar. The folded metal snow rail product tends to work better on lower-pitched roofs. The picture below shows what can happen with this product on a steeper metal roof.

Inadequate Screw Recommendations:

The manufacturer of this product recommends installing these folded-over pieces of metal with number 10 screws. Always install snow guards and snow rails with number 14 or quarter-inch thick screws, not number 10 screws! The manufacturer of these 29 gauge brake bent metal snow rails states on its website that installers can stitch them to the metal roof and not into the substrate below. Metal on metal, as they call it. Installers should never do this with any snow retention system. The heavy weight of the snow and ice can easily pull the stitched screws right out of the metal panel resulting in roof leaks, potential injury, and damage to property on the ground below.

Shape of the Folded Metal Snow Rails:

The folded metal snow rails get installed in both directions. Many of these installations have pointed edges facing the ridge. The pointed side can be angled upward to help cut through snow and ice as it slides down the roof. The building owner should know that when installing snow rails with the pointed edge facing upward, they may only function as snow breakers, breaking snow and ice into smaller pieces. On steeper pitches it can they can act like snow ramps which can have very little function. While this is not always bad, the building owner should be aware of this before installation. The snow and ice that come off the roof are not always tiny and can cause injury or property damage if someone or something is near the roof's edge when the snow slide occurs. Breaking up the snow and ice in this manner and allowing it to slide off a metal roof may be appropriate for the backside of a building if there are no gutters, parking lots, expensive landscaping, or HVAC located at the roof's edge. Our snow rail system is a square or flat bar that the installer can screw into the flat portion of an exposed fastener or clip to the high seam on an exposed fastener roof.

Snow Rail Height Can Be Too Low:

Roofers install these folded pieces of metal on the roof, with the flat side facing the ridge. This installation method may be more effective by placing multiple rows up the roof in equal sections at the recommended intervals. These snow rails come in various heights. Lower-height snow rails are less effective at retaining snow and ice on a slippery metal roof with a steep pitch. More than an inch and a half or two inches in height is needed to adequately retain the snow and ice on a sloped metal roof. The lowest height that a snow guard system can function adequately is two and a half inches from the panel flat. A snow rail should always have an ice stopper extending from the bar down to the panel flat. There is no option for an IceStopper on the folded snow rail systems.

Gimmicky Claims:

Some manufacturers of folded metal snow guards claim that mounting them on the metal roof's high seam allows water to flow under the rails. While this appears to be an advantage, this is not a factor to consider when selecting snow guards or snow rails. It is just a sales gimmick; all snow rails allow water to flow under or around them. To our knowledge, there is not a case where snow guards have ever trapped water on the roof.

Snow retention systems made from bent metal are unlikely to one hundred percent prevent property damage caused by sliding snow and ice on a metal roof for a sustainable amount of time. Furthermore, personal injury and property damage may occur if snow and ice comes off in large pieces.

All screw-down snow retention systems must fasten through the steel roof into a purlin or structural support with proper gauge screws and never just hemmed to a roof seam. It is essential to have a snow retention system that stands at least two and one half inches high from the flat area of the roof panel. Always install snow guards with the flat side facing the ridge to hold the snow and ice in place on the roof.

Final Thoughts About Folded Snow Guards:

This product used to be available at big box stores, but it has mysteriously disappeared from the shelves lately. According to the big box store websites, they cannot even be special ordered. It leaves us to question why these devices are no longer available online at the big box store websites. We price ourselves on being the online "one stop snow guard shop" but not for this product. If you still desire to purchase this kind of snow retention system, they can still be purchased online from other web sites.