Colorado SnowsJune 13th, 2013
By Terry Anderson, Anderson Associates Consulting
Published: Western Roofing – November/December 1997
(Editor’s Note: Terry Anderson has been involved in the roofing industry for 20 years and is the owner of Anderson Associates consulting in Highland, Utah. He is a member of RCI and NRCA. Anderson also serves on the committee for tile roof applications in snow and ice areas for the Nation Tile Manufacturers association. Anderson may be contact at (801) 756-9811.)
The Beaver Creek Ski Resort and Community is one of the premier ski resorts in the Rocky Mountains. Built in the early 1980’s, this Colorado resort sports European design and feeling with tile roofs, stucco and stone exterior walls. The feeling is one of entering a village in the Austrian Alps.
Each year East West Resorts, which manages 16 property owner’s association within Beaver Creek, spent tens of thousands of dollars on the associations’ money to repair roof damage caused by sliding snow and ice. Peter Dan, the vice president and general manager said, “Managing 16 associations is difficult enough without having large recurring expenses that are as unpredictable as snow and ice damage.” Tired of spending so much money on the same problem each year, property owners gave him the task of finding a solution.
Most of the roofs were designed with a cold roof system because of altitude, temperature differential and snow loads ranging from 140-200 psf. Roofs in the “core” area of Beaver Creek are a special blue-green Westile concrete tile. Snow fences had been installed in isolated locations. But each spring, after the snowmelt, East West resorts had the daunting task of supervising repairs in the same area of roofs throughout Beaver Creek. Of all the standard upkeep and repair which was anticipated and budged for, replacing broken tile was one of the homeowners’ greatest expenses each spring. From 1992 to 1995, Dan explored new ideas and suggestions given to him by roofing contractors, roofing consultants and snow retention device manufacturers with each assuring him they had the answer.
After years of this, the manager felt frustrated. He realized what the problems were, but couldn’t find a solution. These were his observations:
- The ridge line designs are different heights which cause snow and ice from high ridges to slide into valleys on the lower ridges sides. The field tiles are crushes as the snow and ice slides downward.
- The greater the distance ridge and eaves, the greater the damage.
- Snow fences weren’t working. The snow load was not distributed evenly and weight of slipping snow and ice would come down on the snow fence, tearing them off in many cases. Field tile would also break above and below the snow fence. Dan determined that he needed a system that didn’t allow this slippage to begin at all. He also noted fences were being destroyed where they stopped at the valleys and didn’t go to the other side of the valley. This situation was causing unequal forces from each side. Snow and ice from the roof area without snow fences slipped into the valley areas which did have snow fences. This force would be too great and would break the tile.
- Snow and ice would slide off the roof slow at first, extending over the overhang and eave one to two feet. Then this compacted snow and ice would break lose. As it fell, it would cantilever over the eaves course of tile, breaking the first course of tile and the damaging roofs and structures below. Danger to people was great.
- When there is a long run between eaves and ridge, more than just one row of snow fences was needed. It would be better to follow the European way of installing fences, about ten feet apart up the roof, providing more equal loads on the roof and stopping tile from breaking high up on the roof.
In an effort to resolve this dilemma, East West Resorts searched again for a system or product that met these requirements: The system should be easily installed into the current tile roof system; would keep the snow and ice on the roof; be engineered based on the roof’s pitch and amount of snow and ice on the roof; and have minimal penetrations through the roof underlayment which would minimize the risk of leaks.
Dan checked the loads his structures could hold and found that they were sufficient to hold the snow weight on the roof. He was then free to keep the snow and ice on the roof and allow it to melt there.
In his quest, Dan found a product specifically designed for concrete roof tiles, Snow Brackets by Tile Roof Accessories, Inc. (TRA). These brackets did exactly what he needed done: distribute the weight of the snow evenly all over the roof, prevent it from sliding, and allow the large amount of weight to be concentrated over the head lap of each tile and battens. It could be easily installed by a unique attachment system to the tile and batten without putting any holes in the underlayment. This was an idea he liked over snow fences.
But most of all, he liked the engineering which has been done by the Engineering Department of Brigham Young University. There, technicians using specialized laboratory equipment had tested the brackets to a fail point in a laboratory and in the field. After analyzing the data, they formulated charts showing how many brackets should be installed based on pitch and snow load. (TRA uses a basis of 2:1 failure with no friction)
TRA gave East West Resorts a specifically designed layout for the Beaver Creek buildings, showing how to place brackets based on the pitch and snowload. Tim Simon of Premiere Maintenance Company was contacted about installed the brackets. Brackets were ordered and custom powder-coated to a blue green color.
East West Resorts’ plan was to hem them installed on a few of the most troublesome buildings and see how they fared during the winter of 1996 and spring of 1997. Dan chose four different roofs and four different exposures. If the brackets worked during the winter of 1996, he would try some more the next year.
To Peter Dan’s surprise, the Snow Brackets worked just like he had hoped and during one of the heaviest snow years in Colorado’s recent history. Dan said, “The TRA Brackets performed very well this past winter. Out test areas were set up at several different exposures and roof configurations. We used them on roofs with valleys, dormers and upper/lower roof designs and they performed superior to anything we have tried. We are phasing Snow Brackets in each year on all our concrete tile roofs.”
Tim Simon, the roofing contractor who installed the snow bracket made this comment, “The installation of these snow brackets is very simple. As the installer, we just had to figure the roof slope and the maximum snowload to come up with the calculation of how many snow brackets to install per square of roof. One this and the installation pattern are figured, they are placed very easily and quickly.” TRA figured the layout pattern for Simon based on his snowload and pitch information.
Because of the great success this year preventing broken roof tile, East West Resorts is planning to try other snow brackets on some copper roofs in Beaver Creek.