Record-breaking snowfalls occurred this past winter in many areas of the United States. The snow, along with icicles and ice dams, also caused another record to be set in many areas - roof damage. Even during winters without heavy snow, however, ice dams cause millions of dollars in damage to schools and buildings. Dealing with ice dams is costly, frustrating and dangerous. Solving the problem depends on an accurate understanding of ice dam formation and the successful implementation of a solution.
It doesn‘t take much for ice dams or icicles to form. Heat from the sun or inside the building melts snow on the roof. Water from the melting snow flows down the roof to the eave, which is colder than the roof over the heated space. If the temperature outside is below freezing, ice starts to form, creating icicles. This ice also builds up on the roof in layers until it becomes a ‘dam’, trapping water that does not freeze and it continues to backup behind the dam. The water is usually hidden under the snowpack, and there is no indication of trouble until a leak shows up inside a school.
Most damage caused by ice dams is apparent. Water-stained ceilings, dislodged roof shingles, sagging gutters, damaged fascia and peeling paint are easily recognized and usually repaired when weather permits. But other damage is not as obvious and often goes unchecked. Water seeping underneath roofs and inside walls dampens insulation and leads to structural damage. Water-soaked insulation, even after it dries, means lower R-values and increased energy costs. Moisture leaking into wall cavities can cause mold and mildew growth inside the walls, creating odors and health hazards.
When ice falls off roofs it can crush cars, decks, railings, landscaping and create unsafe conditions. Each year, hundreds of people are injured - even killed - by falling ice and icicles. Blocks of ice have actually fallen on gas meters, resulting in costly and deadly explosions. "We had some very close calls with falling ice nearly hitting passers-by," says Mark Giblin, Estimator for the Sheet Metal Department at Cornell University, in Ithaca, New York. Giblin does the estimating for sheet metal, structural steel, and slate roofing, and handles material procurement and construction management for the university. "We took steps to prevent anyone from being injured, and also to stop damage to the buildings."
"One solution to the problem is to physically remove ice from the roofs," says Giblin. "We go up on the roof, chop up the ice and remove it. This solves the problem temporarily, but it is labor intensive and dangerous. We also have to be careful because we can damage shingles and roofing systems."
Removing ice is hazardous work, injuring hundreds of people each year. Ice dams range in thickness from a few inches to a few feet. At 60 pounds per cubic foot, ice exerts enormous forces on structures and harms anything in its path. Plus, depending on the roof area above the ice dam, hundreds of gallons of water can be trapped, adding to the dangers.
"The most effective way to eliminate icicles, ice dams and the resulting problems that affect many schools in northern climates is to install a roof ice melt system," states Bob Bylin, President of Bylin Engineered Systems. "A professionally designed and installed system prevents all sorts of problems, especially when valleys, gutters and downspouts are incorporated into the package. The system must eliminate ice dam problems and icicle formation, while keeping snow on the roof, to benefit from its insulating effects."
Bylin, a mechanical engineer specializing in heat transfer, has been creating solutions for freeze protection issues since 1980. He turned his attention to roofs when an associate expressed concern over liability issues regarding falling icicles from one of his buildings. Traditional heating systems did not eliminate the danger of falling ice. Plus, extensive maintenance work was required each spring when melting ice dragged the older-style heater cables off the roof. The result was a patent issued for Bylin’s innovative Roof Ice Melt (RIM) System.
"The RIM system was specifically designed as a comprehensive and customized solution for schools, buildings and homes with common winter roof problems," explains Bylin. "It can be added to any existing structure, or incorporated into the design on new construction projects."
The system takes the concept of clipping heating cables in a zigzag pattern to roofing material one step further. Installation involves strategically placing patented aluminum alloy channels along the lower courses of shingles in areas prone to ice buildup. The panels, which contain electric heating cables are covered with copper or pre-painted aluminum cover panels and go directly on top of most types of roofing material; no removal or replacement is required. Industrial grade cable is used to provide a system that has a projected life of 30 years, the l i fet ime of a typical roof, wi th no requi red maintenance.
"By placing self-regulating heat cables in aluminum channels and covering them with 15-inch wide cover panels, the heat is efficiently distributed over the entire panel surface and less energy is needed to achieve the desired effect," Bylin says. "The system can pay for itself in two or three seasons of not having maintenance personnel or roofing contractors go up on the roof to chop and remove ice and repair the roof damage. A roof ice melt system minimizes ice damage, reduces labor costs, and minimizes potential injuries to workers and passers-by." The cost for a system depends on many variables. A typical system involving 30 to 40 feet of eave panels and two 10-foot valleys, for example, would cost about $3,000. This price includes a fully automated control system, custom design drawings and a full site analysis.
"Before installing a system, it is important to conduct a complete analysis that specifically addresses difficult areas like eaves, valleys and gutters," advises Robert T. Walters, a registered architect and product manager of Beta Design Group, an Architectural Engineering firm in Grand Rapids, MI. "You should also focus on areas of the roof where ice can fall on people below, such as over sidewalks, driveways and entrances/exits."
Cornell University Solves Ice Problem
"We first got introduced to the RIM system in 2001, during a slate roof replacement on a building called the A.D. White House," says Giblin. "The White House is quite intricate. It is a two-story building with a lot of dormers and steeples. We had habitual problems with ice forming in the corners of the building and causing roof leaks."
An outside consultant surveyed the roof of the White House and drew up the plans for the ice melt system. He thoroughly explained to Giblin how the system works and identified problem areas, such as over entranceways and corners where ice damming occurred in the past. The consultant had extensive experience with Bylin‘s RIM system and specified it for the university.
Ice melt systems were actually installed on two different buildings simultaneously. When Giblin was set to do the White House, the project manager for Lincoln Hall wanted the same system installed on his building.
"Our staff installed both systems," states Giblin. "Sheet metal workers set the base panel and our electrician came through with the heater wire and did the connections. The engineers at Bylin were more than helpful and guided us through a lot of the project. The system was easy to install and maintained the historic preservation of the buildings. It blends in very well with the roof."
"A primary concern with older style ice melt systems is aesthetics," comments Walters. "The old way to treat an ice problem was to place exposed heat tape in a zigzag pattern at the roof eaves. The tape is simply placed on top of the roof."
Bylin’s RIM system matches the color and style to blend into existing architectural designs while providing mechanical protection. There is flexibility regarding the type of finished material. It works with the roof and becomes part of the roofing system as opposed to something that is applied to the roof.
"The RIM system keeps ice off the roof and is practically invisible," says Walters. "You don‘t see any heat tape going up and down and criss-crossing the roof. The system blends in and doesn’t intrude on the appearance of the roof. Visually, it is a very good system."
Besides aesthetics, traditional ice-melt systems do not work very well. Most of the zigzag patterned heating systems radiate much of their energy to the atmosphere. Rather than eliminating ice dams, zigzag cables often simply melt tunnels into ice dams and do nothing to solve the icicle problems.
A Permanent Solution
The key to eliminating ice dams and the damage they cause is to prevent them from forming in the first place. The most effective way to do this is to select a roof ice melt system that prevents icicle and ice dam formation at roof eaves and prevents water ponding in roof valleys.
"Our systems have been on the White House and Lincoln Hall for a couple winters now, without any fol low-up maintenance or cal lbacks for any problems," Giblin says. "Record-breaking snow hit Ithaca this past winter and we had no problems on these buildings. If the systems weren‘t on the buildings we would have been up on the roofs chopping ice and removing snow, but we did not get one call on either building. The ice melt system saved us a lot of labor costs and man-hours." Cornell University has roughly 165 buildings and Giblin is trying to identify other areas on campus where ice melt systems will solve problems and enhance roof systems. He will soon be installing it on Sage Chapel. The 200-year-old building has had ice problems in the past on different areas of its roof.
"We just went through a very harsh winter and the ice melt systems passed with flying colors," states Giblin. "We are looking forward to putting the system on Sage Chapel, because we know it will eliminate the problems in the areas where we install it. This is a permanent system and long-term solution."
For more information about roof ice melt systems or ice dams, contact: Bylin Engineered Systems, 888-313-5666 or www.bylinusa.com. Or VT Ice Dam Solutions, 262-646-3070.
Michael Trunko is a freelance writer.