Frequently Asked Snow Guard Questions
- What are SnoBlox-SnoJax plastic snow guards and why are they needed?
- Why plastic vs. metal snow guards?
- What is the policy on price matching?
- Are the dimensions, shape and mounting methods of a snow guard system important?
- Is spacing important?
- Should I use color matched or clear snow guards?
- Do you recommend mounting snow guards with any type of tapes?
- How do I find my roof pitch?
- How many plastic snow guards does my roof require?
- I just want to protect a doorway or vent pipe, any suggestions?
- What is the curing time of the SureBond Everseal SB-190?
- What about cold weather adhesives?
- Is snow guard installation a do it yourself project?
- How do I calculate my Snow Load?
- Can you clarify the recommended use of the SB-190 adhesive?
- Can you use snow guards on TPO or membrane roofs?
- More Questions?
What are SnoBlox-SnoJax snow guards and why are they needed?
SnoBlox-SnoJax is a water clear snow guard, molded of polycarbonate, which sits in the flat part of a metal roofing panel, where it holds the snow and ice in place until it can melt off gradually and safely. They provide ultimate protection for pedestrians and prevent property damage caused by sliding snow and ice. Polycarbonates like Lexan® are UV stabilized and virtually unaffected by weather.
The plastic snow guard came about in 1976, when the late Jack McMullen was receiving negative feedback on metal snow guards in his own metal building business. In addition to getting brittle and breaking in the cold, most of the metal guards of that time period were causing severe dissimilar metal reactions that ended up eroding the metal panel finish. In these cases the conductive liquid or electrolyte was rainwater. During evaporation water becomes concentrated and becomes more conductive, causing the initially benign water to create a dynamic galvanic effect which causes rust. This phenomenon normally begins to occur when water gets trapped in a crevice, such as under a screw or between the base of a metal guard and the metal roof. Even water lying against the face of the metal guard and the metal roof for an extended period time can initiate the deterioration process. Painting the metal guards did not prove to be a reliable solution but it did slow the galvanic reaction process down somewhat. We did find however that with the painted metal snow guards, the corrosion would usually begin to form around friction points and in time would continue to eat its way through the guard and panel.
Generally speaking, the metal guards in each geographical location did not always show identical failures but we did find that the greater the conductivity, the more severe the galvanic effects were. After further research, we also found that salt and industrial pollution significantly increased the conductivity of water so galvanic effects were normally more severe near the coast or in heavy industrial areas. The solution to this problem was the invention of UV stable Clear Lexan™ polycarbonate SNOJAX snow guards! This idea was so unique; it earned a patent in 1978 as the first non corrosive transparent snow retention device.
In conclusion, necessity became the mother of invention for three reasons:
1. If a metal snow guard makes contact with a dissimilar metal type roof panel, a galvanic corrosive reaction (i.e. rust) can occur and prematurely eroded and stain the roof. With plastic guards, this galvanic does not occur.
2. In the cold weather, metal guards (especially cheap castings), may become very brittle, fracture and break. Virgin Grade UV Stable High Grades Polycarbonates do not get brittle in the cold.
3. The cosmetic appearance of a metal roof is altered due to the unsightly metal guards that protrude from the roof surface and do not blend into the skyline while looking up from the ground. The same holds true with painted color-matched guards. Clear snow guards blend well with the sky and roof.
"Don't take the risk of ruining your beautiful metal roof with a non-compatible metal snow guard!"
Our policy is very simple. We will match or beat any published or written Snow Guard price quote from an established reputable snow guard company. The main requirement is that we are matching Apples to Apples and not Apples to Raisins. The competitor's snow guard must be of equal size to our product you are asking us to price match. They must also be made from the same 100 % Virgin Grade, UV stable, Clear, Lexan type material used to manufacture our snow guards. We now have nine different sizes and styles of polycarbonate snow guards so chances are we have just what you are looking for in stock and ready to ship today. We offer the highest quality polycarbonate (plastic) snow guards with the longest proven track record, period! All our guards have been independently tested and guaranteed to work! Do not take chances on new untested designs with prices too good to be true, choose to buy from the originators of the plastic snow guard. We will not be undersold by cheap inferior imitations! Price matching policy is only applicable to snow guards.
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The height and shape of the face of a snow guard determines its ability to hold back layers of ice and snow. A snow guard needs to be mounted in the lowest portion of a roofing panel where the snow and ice actually moves. A flat, non-pointed surface should stand at least the height of the seam, creating a connected field, to hold snow and ice stationary until it can melt off safely. On a standing seam floating type roof, the snow guard should only be mounted with adhesive. This mounting method does not restrict normal thermal expansion and contraction of floating metal roof panels. It also provides a release feature that prevents panel damage. This completely eliminates any potential impairment to the seams. The smooth edges of the SnoBlox-SnoJax reduce the likelihood of personal injury during installation and normal roof maintenance
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The correct spacing of a snow guard system is as important as the proper selection of materials that go into the design of a building. SnoBlox-SnoJax provides fast, free spacing layouts based on the roof pitch, panel runs from the ridge to the eave, panel widths and profile, and the snow load design of the building. We recomend that all customers use the Snow Guard Spacing Tool
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This matter is one of preference. Clear snow guards are far less noticeable on a roof than colored ones. A color matched snow guard will act as a sundial and cast a shadow with the sun all day. Also, if the snow guard is not the same material as the roof, painted at the same time with the same type of paint, the rate of fading will be different. This will make the color matched snow guards more noticeable over time.
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Tapes have very little or no UV stabilization and tend to roll up underneath the snow guard when exposed to shear loads. In our many years of marketing snow guards, we have never seen tapes last very long so we consider this mounting method as temporary. The adherent properties of the tape change with outside UV exposure over time. In our opinion tapes have always been just a temporary solution for mounting a snow guard in cold weather. We only recommend the use of SureBond SB-190 clear sealant adhesive for adhering SnoBlox-SnoJax. Note: There is no long lasting adhesive available for copper or lead coated copper.
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Using any builders level placed downhill anywhere on the roof. Measure out 12 inches on a horizontal level plane. Measure up from the roof surface to the 12 inch mark on the level. This number is then placed over 12 (i.e. 4/12). Congratulations you have just measured the pitch of your roof.
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This question is best answered by using the Estimator link above. You will need to know the roof pitch as described above, a rafter length (or run) and width of your metal panel flats between the valleys. Please note where the minor ribs fall in relation to the size of the base of the snow guard product you are interested in purchasing. Use the Project Estimator for an instant project estimate and price quote.
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We market a product made just for vent pipe and chimney protection called VentSaver. Protecting just a doorway is a tricky proposition. Even though we don't recommend it, in some areas of the country where the snow doesn't frequently freeze together it is possible to retain snow on partial roof sections. In potentially cold climate areas that have snow and ice accumulate and freeze for several days at a time, the disproportionate loading that is created, extends well beyond the secluded area of guards. This imbalanced type of load is usually detrimental to any type of snow retention device. The general rule of thumb is that snow and ice guards should be equally staggered over the entire roof so the loading is distributed uniformly. Most engineers agree it is better to have equal loading verses unequal loading on a building structure.
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When used with our SnoBlox, SnoJax II & IceJax, the SureBond EverSeal SB-190 requires at least 672 hours (28 days) of cure time with temperatures of 50° Fahrenheit or above to adequately cure prior to being subject to a snow load. The curing process does not have to take place all at one time however it is essential that a cumulative total of at least 672 hours of 50° F. is attained. The adhesive is not ruined in cold weather, instead it just enters a dormant stage until temperatures rise above 50° F. In many instances the delay caused by cold weather can actually double or triple the 28 day curing period.
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Since 1985, we have spent thousands of dollars testing tapes, sealants and adhesives and in our opinion the only adhesive that works is the SureBond SB-190. The only minor drawback is the specific time and temperature requirements that prevent winter time installation. To our knowledge there are no miracle “cold weather” adhesives, tapes or sealants that work and although, we are the biggest fans of the SureBond brand of products, we feel obligated to caution against using what several competitors are touting as the “New Cold Weather Adhesive” called SureBond EverFlex Bondaprene 1800. Just ask to see their professional snow guard testing results and project references for this new product and you will see what we mean!
If considering an adhesive tape method of bonding, “Buyer Beware”! We encourage you to carefully read the installation instructions. In addition to thoroughly cleaning the panel surface, a harsh primer is recommended before applying the tape. They also recommend sealing the perimeter of the guard with a bead of the SB-190 or a private labeled brand of SB-190. The end result; 6 months after the sun’s UV rays disintegrate the tape, the only thing that may still be holding the guard to the panel is the bead of SB-190. In conclusion, we feel the tape gimmick is a smoke and mirror tactic that some manufacturers offer for a quick or cold weather adhesive application.
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Snow Guard installation is a reasonably straight forward process, see our installation page for details on the 3 easy steps. Unless you are familiar with walking on steel roofs, we recommend finding an experienced local metal roofing contractor. Since we are the manufacturer, we do not install snow guards nor do we make specific contractor recommendations. If you decide to tackle the job yourself, it may be worthwhile investing in a shoe made specifically for walking on roofs such as Cougar Paw shoes seen at www.cougarpaws.com. IceBlox Inc. d.b.a. SnoBlox- Snojax does not assume liability for the installation process or recommendations of its products.
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Please call your local zoning office or county building inspector. Your local building supply store or lumber yard may also know the local snow load values.
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SureBond SB-190 is the only adhesive recommended by SnoBlox-SnoJax. It requires 28 days or (672 Hours) at 50 Degrees (F) or above to achieve full cure. Temperatures below 40 Degrees (F) will delay the cure time, until temperatures reach 50 Degrees (F) or above to completely cure. The user must always determine the suitability of the products for their intended use as we do not stand behind the method of attachment for our snow retention systems due to the lack of control over workmanship. We also recommend that a manufacturers spacing layout is used for appropriate placement of the snow guards for maximum protection, assured satisfaction and validation of the warranty.
Glue Down Applications:
A chemical reaction takes place between the plastic and the solvent base of the SB-190. Over 28 days the SB-190 actually chemically welds itself to the polycarbonate snow guard. Not all plastics can withstand this type of chemical welding without loosing integrity, but we have found that after 22 years of selling the SB-190 product, it does not affect the high quality polycarbonate we use. Visit our test results page to see holding power of the SB-190 on our snow guards.
Screw Down Applications:
SureBond SB-190 is not recommended as a sealant for use with mechanically fastened snow guards. Though we have never experienced a snow guard failure as a result of using the SB-190 in conjunction with screws, we have experienced minor crazing around the screw holes after 30 days. The crazing is usually more evident when using the SB-190 as a sealant when screwing down the snow guards into a steel purlin rather than a wood purlin. As mentioned in our installation instructions sheet, a screw down application of snow guards should have 100 percent clear silicone or equal, uniformly covering the entire underside before placement. The screws should then be snug tightened to about 50 percent compression of the washer.
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The method of attachment is the biggest concern with all membrane roof systems so the answer depends on your decision to screw fasten the snow guard system over top of the membrane and secure it into a structural support below. If a mechanical method of attachment is used, then our screw down polycarbonate snow guard systems are an excellent choice.
We would not recommend using any type of adhesive to fasten snow guards on membrane roofs because excessive shear loading cause by the weight of the snow and ice could cause stress and premature failure of the roofing membrane.
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