Ice Dams: Answers to Five Frequently Asked Questions By Matthew A. Drewes, Esq., Thomsen Nybeck, Attorneys at Law
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ce dams are all too common during Minnesota winters. They may happen for a number of reasons, and there are debates about whether they should happen at all. When they occur, arguments frequently arise about how to take care of the problem. In common interest communities this also leads to disputes about who is responsible to perform the repair work and, more importantly, who should have to pay for it. Sadly, winter again is approaching, and for many, ice dams will follow. This article will review the causes of ice damming, the various parties who may have responsibility to pay for repairing the damage, and who might have the responsibility to correct the problem. What Are Ice Dams? Ice dams are characterized by a buildup of ice at the edge of a roof. They occur when snow accumulates on a roof and the surface of the roof is heated sufficiently to melt the snow, while the eaves (the portions of the roof more exposed to the elements) remain below freezing due to cooler outside temperatures. Icicles may form as a result of ice dams, but the presence of icicles does not necessarily signal the presence of ice dams. That said, it’s better to be safe than sorry, and if you’re in doubt you should react as though you have ice dams until you receive a credible confirmation that ice dams are not present. What Causes Ice Dams and How Do They Cause Damage? Sunny winter days, which are common in Minnesota, frequently contribute to ice dams. What many people don’t realize is that one or more other factors usually cause the ice dam. Some builders or their representatives will contribute to the confusion about the nature or cause of ice dams by attempting to excuse their presence. They may assure homeowners that ice dams are normal and unpreventable, or that the problem is caused by the homeowner’s or the association’s failure to maintain its roofs properly, or instead 8
Minnesota Communit y Living
that the problem has arisen due to abnormal or extreme weather conditions that could not have been foreseen. In fact, ice dams should not occur and in most cases are preventable, though fault and financial responsibility may present some thorny issues. The two most common causes for ice dams are found inside the structure. The first cause is “bypass air” from the dwelling that enters the attic, and the other is inadequate ventilation inside the attic space. In some ways the direction a building faces may contribute to the problem, as can certain architectural styles or features, but at least one of the two issues listed above are usually involved when an ice dam forms. The term “bypass air” refers to warm air from the dwelling that finds its way into the attic and, during the winter, can start to warm the underside of the roof. This warm air may actually leak through light fixtures or other openings between the dwelling and the attic, or it can result from insufficient insulation in the attic, allowing ambient heat from the unit to rise into the attic. It is also possible that air ducts or other ventilation systems may leak or radiate heat into the attic. Service providers exist who can perform a “blower door” test that determines whether there is excessive air escaping from the living area into the attic space of a structure. Some even work through government-subsidized programs to make their services more affordable. A ventilation issue arises when air flow in the attic itself is inadequate. Roofing systems are designed with vents near the peak and vents in the soffits. The soffit is the horizontal surface, usually made of painted metal, that you see when you look up at the underside of the eave of your roof. These vents exist to permit air to rise up through the soffit, flow along the underside of the roof deck, and escape out the vents near the roof peak. When this air flow occurs uninterrupted, the surface of the roof is more likely to say a relatively uniform temperature from top to bottom, limiting if not eliminating the temperature variations that can cause the upper areas of the roof to be warm while the lower areas of the roof remain cold (the cause of ice dams).
If insulation blocks this ventilation because it is filled or packed against the underside of the roof, inconsistent roof temperatures characterized by warm upper roofs and cold lower roofs (the cause of ice dams) can result. Ironically, insulation intended to limit the amount of bypass air in the attic can cause ice dams by blocking needed ventilation. Of course, water leaks need not occur just because there are ice dams. Proper roofing techniques can help protect against water damage even where ice dams might form. This primarily means proper installation of an “ice/water shield” a sufficient distance up the roof, and also protecting the bottom edge of the roof, where it meets the fascia. Ice/ water shield can protect the roof edge, but some contractors will install a metal “drip edge” at this location to protect against voids between the roof deck and fascia where water can enter. Gaps or openings that allow water to enter when it backs up under the shingles should not exist at or near roof edges. Consider also that just because you haven’t seen water inside your home does not mean that water has not entered the structure. Water reaching the inside of a building violates building code and constitutes a major structural defect whether it enters the dwelling space or not. How Should You Respond if You See Ice Dams? If you see ice dams on your home or in your community, ensure the association’s board of directors and the property manager, if any, know about the ice dams and any resulting leaks. Provide the notice in writing as quickly as possible. The association and any affected unit owners should then cooperate for the purpose of making an inspection of the roof and attic —and the unit, if necessary— to investigate the cause of the ice dams and any damage arising from them. If your community is less than 10 years old when you first notice the ice dams (or if the ice dams occur within 10 years of a renovation to the building) you should also provide written notice to the developer, builder or contractor, as applicable. Do this immediIce Dams Continued on page 16