Alpine SnowGuards is entering its 5th year of performance testing snow guards at its Morrisville, Vermont facility. Recently, two of the 12 roof types were retrofitted with DaVinci Roofscapes’ multi-width shake and single-width slate:
- DaVinci’s multi-width shake in the color Autumn was installed on a steep 12:12 pitch roof with Alpine’s powder coated Fusion-Guards to match in a 18 per roofing square pattern
- DaVinci’s single-width slate was installed on a 7:12 pitch with Alpine’s half round PD40 snow guards in the standard layout pattern of 18 per roofing square
Alpine is as interested in snow guard performance on different pitches as it is in how products perform on different synthetic roofing materials.
“It’s time to do an investigation and find out just what the level of performance is for different types of pad-style snow guards based on different roof slopes, different snow loads, and different types of roofing products,” explained Alpine’s technical sales manager, Kris Michaud.
“DaVinci is doing a really good job in the marketplace; they are pioneers in the composite tile market,” said Michaud. “That is one of the main reasons we want to work with them as the leading snow guard manufacturer.
“DaVinci’s products are installed all across the country in all kinds of climates. One of the most important things to come from that is the knowledge that composite tiles are very slippery. While their products are incredibly good, they do present new issues for customers who change from a cedar shake or asphalt shingle roof to one with these slippery products that snow slides off from.”
Located less than 20 miles from the 4393’ highest peak in Vermont, Mount Mansfield, Alpine’s facility captures performance data 24-7 throughout the long winter season. Alpine used an 80 psf ground snow load to produce the layout of the snow guards on the test facility.
“There’s quite a bit of significant drifting on the 12/12 side of the performance facility that happens frequently from wind-driven snow. So that roof in particular sees snow accumulation at the peak. We’ll get into more of that as we go through some of the test results, but it’s an important thing to understand and see on the roof.”
“What we want to know is whether the very short half round pads work on a composite slate that’s ⅝” thick when it’s on a shallower pitch like a 7:12,” explained Michaud. “ We know from customer feedback that the performance on a steeper pitch with a shingle that thick is less than it would be on a slate roof with a similar thickness. Most slate roofs are less than ½” thick. So that’s an important distinction also. The DaVinci slate roof is meant to mimic a very high end slate roof with a thicker slate and that’s one of the benefits you get from the DaVinci product.
“When we flip around to the front roof, the multi-width DaVinci shake product is thicker at about ⅞” thick. What we’re looking at on the steeper pitch is a taller snow guard in the Fusion-Guard that also has the same width head as the PD40. The width is higher on Fusion-Guard, where the PD40 is the widest at the base where it interacts with the roof surface.
“Fusion-Guard is widest at the top of the snow guard where it interacts the most with the snow when it’s deeper. So what we’re looking for is how do these different snow guards perform in these different scenarios. That’s our test strategy of our different products on different DaVinci products and now we’re just waiting for snow to see how these events play out.”
Performance Test Findings Specific to Alpine’s Products
Alpine’s facility is well-rounded with an asphalt shingle roof, two metal corrugated roofs, a slate and tile roof, stand alone roofs for membrane and solar panels, and LedgeGuard.
“We’ve collected a lot of data and we’ll continue to test our products both in this performance aspect as well as structural testing inside our own facility,” said Michaud. “Our findings can be somewhat generalized but they are very specific to the shape of our products, to the height of our products, to how our products are laid out because the way that we lay our products out is different than any other manufacturer. So, all of those things combined to make these findings specific to what we do with these roofing products.
“If you lay them out in a different pattern, they may not behave the same way even with the same density. So that will be something we will be pursuing in the future as we test more scenarios.”
For more information, check out:
“Testing Snow Retention Systems for DaVinci Composite Tiles”
“Performance Testing Alpine’s Snow Guards, Winter 2023 – 24“