Snow Retention Frequently Asked Questions
When snow avalanches off of a rooftop, it can damage anything in its path! This sudden release of snow can be dramatic—dumping tons of snow all at once. Learn how to retain roof top snow safely, and all your questions answered in this article.
Why keep snow on the roof?
When snow avalanches off of a rooftop, it can damage anything in its path! This sudden release of snow can be dramatic—dumping tons of snow all at once. Falling snow forms a temperature-sensitive bond to the surface of a metal roof. As that roof is warmed, whether from the sun or from building heat loss, the bond with the snow is broken and a thin film of melt water serves to lubricate the roof. This can have dramatic results as a several-ton blanket of snow suddenly slides off the roof and avalanches down upon anything in its path: gutters, vehicles, landscape, even people. Once piled up below, that same snow bank can go on to cause additional troubles, like direct damage to the building walls, or even indirect damage caused by funneling melt water into, rather than away from, the wall. This is what makes snow retention devices desirable: they hold the snow back and allow it to leave the roof slowly, either in small amounts of snow or as melt water, avoiding the dual calamity of the avalanche.
How are S-5!® snow retention systems attached?
S-5! Snow Retention Systems are attached using S-5! clamping technology. S-5! attachments are all mechanical, and squeeze the seam with round-point setscrews. S-5! attachments features and benefits:
- No unreliable adhesives
- No panel penetration
- Do not violate the panels’ thermal movement
- Unequaled holding strength
- No premature corrosion
- Do not violate roof system warranties
- Recommended by all leading metal building and metal panel manufacturers
S-5! clamps use round-point setscrews to firmly grip the seam of a roof without penetrating its panel material. S-5! clamping technology is so unique that it carries its own patent.
Compare approaches: Copycat clamps use “cup-point” screws that cut through the paint and protective coating on roof panels, allowing corrosion to set in while voiding the warranty on the roof. But S-5! clamps come with our , round-point setscrews which are guaranteed not to puncture your panels or affect your roof’s warranty. S-5! Has done 1000 hour ASTM B-117 Salt Fog testing on S-5! system clamps, attaching them to painted Galvalume® and galvanized panels. The result: Zero corrosion. In addition, S-5! customers can rest assured that all related hardware is noncorrosive, 300 series stainless, not plated steel.
The S-5! attachment method has been thoroughly tested for tenacity, and has proven itself unrivaled in the industry. And since the holding strength of any clamp will vary across different roof profiles, material types and gages, S-5! performs hundreds of independent laboratory pull tests on every roofing type available, and we’ve posted the results for your review here.
With an ultimate load-to-failure average of over 1,800 pounds (and as high as 3,000+ pounds), S-5! clamps remain unsurpassed. In fact the holding strength of our clamps is up to ten times greater than alternative products!
Can S-5!® snow retention systems be retrofitted to an existing roof?
Yes, ColorGard®, X-Gard™, DualGard™ and SnoFence™ can easily be retrofitted to existing roofs or incorporated onto a new construction design. They can be installed any time of year using power tools that are common to the trade.
Yes! Contractors everywhere love the ease of assembly, the simplicity, and the durability of S-5! snow retention systems. This should come as no surprise, because S-5! systems were designed by a contractor who was tired of inferior products that were wretched to install and performed poorly. These systems were then field tested and refined in the Colorado Rocky Mountains where snow challenges are extreme. The result was a line of unsurpassed snow retention systems based on S-5! clamping technology.
Why upgrade from adhesive-based systems?
Today’s metal roof products have premium finishes made from fluorocarbons which are similar in composition to Teflon, the popular non-stick coating on cookware. These paint resins, Hylar® and Kynar® by tradename, are wonderful performing finishes that were never intended for the glue-on type snow retention systems. People continue to try testing this combination, but an adhesive device on a nonstick surface continues to offer high failure rates. In addition, most adhesives are temperature-cure compounds. This limits their application to warm weather only, and the glues can take weeks to fully cure.
Note, too, that adhesives are chemically organic compounds. Ozone and ultraviolate light cause the chemical bonds to degrade over time. This means that an adhesive tested for ultimate load-to-failure in a laboratory may well show favorable results. But after five or ten years of exposure to heat cycling, UV radiation, moisture and ozone, the weakened chemical bond often causes the system to fail at unacceptably low loads. Will that happen on your roof? No one can say for sure, and it’s that very issue of unpredictability that makes adhesives a risky choice. Our S-5! attachment technology, on the other hand, is mechanical, stable and predictable. It’s derived from non corrosive metals that are unaffected by temperature, UV light or ozone. Their attachment performance does not change over time—if you love it today, you’ll still love it 50 years from now.
Note: When relying upon lab tested load figures, the setscrew tension should be periodically verified using a calibrated wrench.
Should the snow retention system be customized to the job?
Yes—any product should be—including those sold by other companies. Everything has a failure point, which is why products are tested. The idea, then, is not to expose a product to forces which exceed its known point of failure. These forces are predictable and can be calculated accurately for any application. Contact us for assistance at 770-405-1060 M-F 8am-5pm or at firstname.lastname@example.org
What about cost?
S-5!® snow retention systems are the best buy on the market! Better holding strength, better color retention, user-friendly installation. But this all equates to higher cost, right? Wrong! Everyone wants better quality—as long as it costs less. Well, with S-5! snow retention systems you can have your cake and eat it too! When compared with other fence-type systems on a cost per foot basis, S-5! wins, hands down—even though it is several times stronger than most of those systems. When compared to individual cleat-type units, pound-for-pound on holding strength, S-5! costs much less—yes, even less than the plastic parts. Installers prefer S-5! so much that they often charge less to install S-5!.
What is the approximate linear foot cost of a ColorGard® system?
Pound for pound of holding strength, S-5! ColorGard is the best buy on the market, but because ColorGard assemblies are designed to the specifics of each project, costs vary widely depending upon those specifics.
The variables are as follows:
Clamp Frequency: Based on seam spacing; also sometimes you can skip seams depending upon design loads.
Clamp Model: Based on seam and profile- some clamp models are more expensive than others.
Use of SnoClip™: In some cases SnoClip is optional and may be omitted from the assembly.
Purchase Quantity: S-5! components use columnar pricing according to order quantity. The larger the order the lower the unit costs.
Following are examples of how these variables can affect cost:
Clamp spacing: Seams are 16” on center. But the design service load requires a clamp only every second seam
Clamp model: The profile is 1.5” double folded, requiring the S-5-E, our lowest cost clamp.
SnoClip: Seam height is 1.5” and user has elected not to use SnoClip.
Purchase Quantity: Total assembly length required: 2,700 ft
Part takeoff consists of:
- (1013) S-5-E clamps placed on every other seam
- (338) Pieces of 8ft ColorGard
- (1013) VersaClips™
- This job will cost about $4.51 per lineal foot.
Clamp spacing: Seams are 16” on center. The service design load requires a clamp to be used on every seam.
Clamp model: The special profile requires the S-5-Z.
SnoClip: Seam height is 2-3/4” and SnoClip III to be used at every panel.
Purchase Quantity: Total assembly length required: 24 ft
Part takeoff consists of:
- (16) S-5-Z clamps placed on every seam
- (3) Pieces of 8ft ColorGard
- (16) VersaClips
- (15) SnoClip III (every 16”)
- This job will cost about $13.79 per lineal foot.
The above figures are based upon Manufacturers suggested pricing and do not include freight, tax or color strip. Color strip is sometimes made from scrap and in such cases is a zero cost item. In other cases it may cost up to $0.35 per foot if specially fabricated from outside sources.
We have chosen examples from opposite ends of the spectrum for purposes of illustration. Most jobs will fall somewhere between. RapidMaterials has trained staff on hand to assist you with determining quantities. Contact us at 770-405-1060 M-F 8am to 5pm Eastern, or at email@example.com.
How do I know which system to choose?
If there is a design objective to color-match pre-painted steel or aluminum roof material, then ColorGard® is the obvious choice. If the project involves mill finish, traditional folded standing seam or batten seam copper, then brass SnoRail™ or SnoFence™ is the perfect solution. If the design calls for slender, cylindrical shapes, look at SnoRail or SnoFence in mill-finished aluminum. For projects with high snow loads and wide seam spacing, X-Gard™ 1.0 and 2.0 are the answer. When architectural specifications call for a 1? pipe system, look no further than DualGard™.
How far do you set ColorGard® from the eave and how far do you set back the second row?
Determining where to place snow retention rows is a common question. The first row is the easiest to answer, but it is really more of a question. How much snow do you really want to fall off the roof?
The Metal Construction Association “Metal Roof Design for Cold Climates” document has some commentary on pages 10 and 11 with respect to the first row of a snow retention system. This industry document recommends, “The first row of units or cross-members should be located close to (within 12-in. of) the eave end of the panels.”
The reason for this recommendation:
“This is because at some point, the snow bank that envelopes the snowguard will shear at the approximate location of the guard, and whatever portion of the bank is below the guard may fall from the roof.”
You will find several myths surrounding this topic, but the sighted “Metal Roof Design for Cold Climates” published by MCA is a good source of information to determine this and other cold climate designs. This document explains this question as well as many others regarding snow retention and metal roofing in cold climates.
Figure 11 “Guidline for spacing of multiple rows” is a helpful resource found on page 10 of the MCA “Metal Roof Design for Cold Climates.” As you can see from the Figure 11 layout, snow retention products are preferred near the eave, this is to take advantage of the compressive and shear strength of snow pack rather than being dispersed all over the roof surface.
Another issue that is often overlooked, and can be very critical, is the need for a second row, even when calculations say you don’t need one. This is explained in the sighted document and is caused by a lack of compressive strength in the snow. We at S-5! like to call it a “Buckling Blanket.”
A Buckling Blanket is when the blanket of snow on the roof is dense and wet (not solidified), it may tend to undergo compression buckling, pushing a “loop” upward from the roof surface as the heavy mass compresses toward the eave where it is restrained by snow guards. This loop can fold over the blanket and the snow retention device(s) in the downslope direction, often breaking and in some cases falling from the roof or impacting lower rows of assembly. A simple solution is to reduce the unsupported length of the snow blanket by adding rows of snow retention. For more information please see: Buckling of Snow.
The MCA “Metal Roof Design for Cold Climates” document has other useful information in it with respect to this issue. For more information about MCA please visit their website: www.metalconstruction.org or click here to download the PDF document entitled: MCA-Cold Climates
When should stainless steel SnoRod™ be used rather than aluminum?
The stainless steel SnoRod is more durable than aluminum, and suggested for projects where greater durability is needed, or when the stainless finish is desired for aesthetic reasons.
When should SnoFence™ be used rather than SnoRail™?
SnoFence is somewhat stronger than SnoRail. Use it for increased durability or when the aesthetic look of two rails is desired.
When should SnoClips™, X-Clips™, or DualClips™ be used and how many are needed?
SnoClip, X-Clip, or DualClip will stop or retard the passage of snow and ice beneath the snow retention cross member. If other flashing elements (e.g., eave guttering accomplishes this purpose) are utilized, then it may not be necessary—so its use is somewhat discretionary, depending upon the eave details and project specifics. We recommend it in most cases. In general, one SnoClip per panel on the first row of snow retention will suffice. When seam spacing is >24?, two or more SnoClips per panel are recommended.
IMPORTANT NOTICE: SnoClip design has changed. SnoClip must now slide on from the end of the ColorGard® cross member. Be sure to slide SnoClip onto assembly before attaching cross member to clamps.
Why is ColorGard a better choice than the other color-coded options?
Because of the perfect color matching—that lasts for the life of the roof! It is no trick to achieve a perfect color match to the roof initially; numeric computer matching has made that task simple. The challenge is to keep it color-matched over time and exposure, because different pigments, paint resins and application technologies result with different aging characteristics. One paint fades much more rapidly than another, resulting in a very unsightly mismatch after several years.
The list of snow retention products continues to grow, and every manufacturer claims to be the best, the leader, or the “premier choice.” Sorting the facts from the sales rhetoric can be tiring. But ColorGard really does differ from all others, and we back our sales pitch with a warranty: ColorGard is the only product available that will perfectly match the roof color for the entire life of the roof.
The premium paint finishes used on metal panels are “coil-coated.” This paint application method utilizes state-of-the-art technologies, chemical pretreatment, primer and finish coat application, and controlled oven curing. Only through this lengthy process can high quality Kynar and Hylar (PVDF) finishes be applied and warranted against color fade for 20 years and longer. Our competitors have tried everything in their attempts to match the color and performance of factory coil-coating methods: Anodizing, powder coating, dye and air-dried paints—even powder coating with Kynar resin. But nothing ever comes close. Even when these methods produce perfect paint matches, the match doesn’t last. In a few short years the inferior paint on the snow guard reveals itself as it fades noticeably faster than the roof, creating an effect that is strikingly unattractive. Even powder coating with Kynar resin cannot equal the performance of coil-coated Kynar.
ColorGard is the only product that uses the same factory applied (coil-coated) finish and inorganic pigments as the roof itself. We do this by incorporating a strip of the actual roof material in the ColorGard system, for a perfect match of roof and snow guard—forever!
How is ColorGard attached?
With S-5! clamping hardware—the trusted name in metal roof attachment technology worldwide. ColorGard does not rely upon adhesives for attachment to the roof panel.
Why does that matter?
The premium finishes used on today’s metal roof products are fluorocarbons—“Hylar” and “Kynar” by tradename. These paint resins (polyvinylidene difluoride or PVDF) are similar in chemical composition to “Teflon,” the popular non-stick coating for pots and pans. Indeed, the benefits of this type of paint are related to its non-stick characteristics. Gluing a device to a non-stick surface results in a rather unreliable performance and a high rate of failure. In addition, most adhesives are temperature-cure compounds, which means that they can only be applied in warm weather and require weeks to cure, limiting their installation seasonally.
Is there a way to use ColorGard on other roof types?
Yes. With S-5!® VersaBracket™, and CorruBracket™ ColorGard can be used on almost any roof type, including face-fastened metal panels and even non-metallic roofs.
If you have a face-fastened, ribbed panels, or other non-metallic roof, our VersaBracket is the fastener for you! It requires no messy sealants and leaves you with no risk for leaks. That’s because the VersaBracket comes with factory applied sealant already in the base to waterproof its attachment. Simply peel the release paper from the base.
The ColorGard crossmember easily fastens to VersaBracket with self drilling-screws. Choose a pre-painted metal color strip, or use ColorGard without a color strip. Either way, ColorGard will offer great performance and beauty for decades to come.
How can ColorGard be less conspicuous than CLEAR plastic?
ColorGard presents architecturally clean lines. It is unobtrusive in appearance, blending into the roof-scape. When compared to plastic alternatives that have highly reflective characteristics, ColorGard is the clear winner for complementing the roof.
Clear plastic alternatives are often presented as being inconspicuous. Manufacturers claim that they are “practically invisible” due to their “colorless transparency”.
“Clear” plastic snow guards (left) vs. ColorGard on matching roof (right). Which one is really less conspicuous?
What manufacturers neglect to say is that these plastics are petroleum derivatives that change as they age. The sun’s ultra-violet rays draw out the oils and plasticizers leach out of the material causing the material to yellow with time.
A few short years in the elements causes clear plastic to dramatically discolor.
Because these products generally have low load-to-failure values, they must often be used in a very redundant fashion to avoid overload and failure. Because of ColorGard’s Herculean strength, less ColorGard is required. Based upon lab tested load-to-failure data, it can take up to 10 plastic parts to equal the strength of just one row of ColorGard.
The appearance of these buildings is marred by roofs “polka-dotted” with clear plastic snow retention devices.
I have seen other products that attach with setscrews. How is S-5!® different?
The metallic and architectural coatings used on many sheet metal panels are thin and fragile. There may be copycat snow guard products in the marketplace that also utilize setscrews for attachment, but be careful! A common setscrew with a cup-point gouges through protective coatings, violating warranties and causing corrosion sites at the point of attachment. Only S-5! utilizes special, polished, round-tipped screws. Although more costly, the makers of S-5! use this method to preserve delicate panel finishes, and their warranties. This is why all major metal roof panel manufacturers approve and recommend S-5! products—often on an exclusive basis!
Designing a special screw for our S-5! product lineup was only the beginning. We then conducted ASTM B-117 salt spray weathering tests on panel seam specimens to determine whether these screws caused any damage, however slight, that could result in premature corrosion. After 1,000 hours in the salt chamber, no corrosion was detected at any of the setscrew locations! In fact, S-5! offers the only setscrew-based attachment system on the market that puts neither your roof nor your roof warranties in jeopardy!
We also use the highest quality (18-8) stainless steel alloys for all S-5! hardware, and include auxiliary stainless mounting bolts and washers with each clamp to assure longevity and metallurgic compatibility—no matter what the attachment application.
S-5! attachment technology has been in use on rooftops since 1992. Over the years it has come to be recognized, recommended and even distributed by leading metal panel manufacturers the world over, many of whom will approve no other method for rooftop ancillary attachment.
Why S-5!® clamps?
Because S-5! clamps attach almost anything to standing seam metal roofs without piercing the panel! S-5! clamps are available for virtually any panel profile on the market—architectural and metal building panels. S-5! clamp technology involves gripping the seam in such a way that there is no penetration to the panel material. We utilize , round-point setscrews for attachments that are specially made only for the S-5! system. S-5! never uses “cup-point” screws like all the copycats do. Such a screw point cuts through the paint and protective coating of standing seam panels, causing corrosion and voiding warranties.
We have done 1,000-hour ASTM B-117 salt fog testing of our attachment to be sure that it causes NO CORROSION on painted Galvalume® or galvanized panels. All related S-5! hardware is noncorrosive 300 series stainless, not plated steel. The tenacity of the S-5! method of attachment is thoroughly tested and unequaled by other products.
Holding strength of S-5! varies on different seam profiles, material types and gauges—and we have tested our products on all those different panel seams, doing hundreds of independent laboratory pull tests.
What does all this prove?
It proves that the holding strength of the S-5! clamp is absolutely unsurpassed. Ultimate load-to-failure of S-5! averages over 1,800 pounds—with values in some cases over 4,000 pounds! This kind of strength is up to ten times stronger than alternative products.