Why a Roof Leaks After a Snowfall – and What Can Be Done

If a resident calls to report about a roof leak after one or more snowfalls, it’s possible that an ice dam is the culprit. One of the biggest cold-weather problems is ice damming, which is not a fault in the roof itself but a reaction between snow and ice buildup, and potentially, the insulation conditions below. It’s important for association board members to know what causes ice damming and how it can be repaired, before you face an emergency situation.

An ice dam is a ridge of solid ice that commonly forms along the eaves of a roof. During a natural freeze and thaw cycle, especially with rapidly changing temperatures, ice dams can easily form in condominium association buildings. It doesn’t take much more than an inch or so of snow or ice to block natural runoff at the edge of a roof. Once in place, though, it prevents further snow melt from draining into the gutters. Instead, all that melting ice and snow is dammed up and can seep under the edge of the roofing materials.

However, an ice dam doesn’t mean that there’s a problem with the roof. On perfect shingle roof installations leaks still occur when large ice sheets and ice dams form during the winter. That is because shingle roofs are designed to keep out flowing water, not standing water. Standing water goes underneath shingles and through normal nail holes in felt. When an ice dam is formed, it is an indication that there’s inadequate insulation inside the crawlspace or attic that is letting heat escape. Though excessive heat may seem counterintuitive to forming ice, the escaping heat will warm up most of the roof, where the snow will drain quickly to the colder edges of the roof, and then build up a ridge that prevents further draining.

In addition to leaks, there are several other problems that can occur with this issue. The weight of the ice can damage gutters by warping and bending them downward; the ice can have sharp edges that wear and tear on the gutter materials. When you see a gutter filled with long, thick icicles, it is one sign that ice damming is present and should be addressed – and the icicles should be removed before they fall and hurt someone. Even without gutters, though, an ice dam can form along the edge of the roofline and produce seepage inside.

Products such as Ice & Water Shield and other similar treatments prevent most ice-related winter leaks; however, leaks can still occur on perfect roof installations. When ice damming conditions exist on roofs that have not leaked during rain, there is rarely a defect as explained above. As a result, it usually doesn't make sense to send a repairman since the roof itself doesn’t have a fault. Instead, there are two approaches to handle the problem and prevent future issues.

Resolving the Ice Dam

In community association law, the roof is considered a common element that the association board has a duty to maintain; thus, the board of directors is responsible to address persistent, recurring ice dams. They can hire a specialist to remove snow with special snow rakes and the ice can be chipped away. De-icing products may be used on the roof and in the gutters. On large roof areas, though, such as a large condominium building or townhouse row, the snow removal cost may be prohibitive. The association board may decide instead to let it melt as the weather changes. It’s possible that cutting out the ice dam from the area that is leaking or applying ice melt to make channels through the ice will have a positive effect.

Depending on the association’s insurance, as well as the bylaws of the community association, the resident may be responsible for fixing any damage from water leaks inside the home. The resident should contact their homeowner’s insurance company for direction. Note that this can be a disappointing message for residents to hear. Water damage due to a fault in the roof can look the same as water damage due to an ice dam, and they may not understand why the association’s insurance would cover one and not the other. The association board should work with their property manager to develop a message that will fully explain the situation and give homeowners the guidance they will need. Remember that ice dams can be a one-time issue and be sure to share that information.

Preventing Ice Dams

Roofing codes require roofers to install ice damming membrane in the areas most likely to trap water under ice. The ice damming membrane can keep water out for approximately 48 hours. During that time the water usually refreezes or drains when it is warm. Ice damming membrane eliminates nearly 100 percent of leaks under average winter conditions. It fails when water sits too long under ice. Also, water gets beyond the membrane when the ice sheets extend beyond the area it is installed. Unfortunately, there are no good construction solutions for this problem on shingle roofs. The only solution is to melt or remove the ice which would need to be redone each time extreme ice conditions occur.

With roofs that have had a persistent problem with ice dams, there are other methods to resolve the issue. Heating cables can be installed in the roof that will break up melting ice. A roofing inspector can determine if there are particular areas that are failing in the roof or if damage is causing the ice to be worse or more persistent. Note that these remedies are likely to be expensive and may need a capital project investment to resolve.

Inside the home, all possible areas of warm air leakage should be addressed. Additional insulation is always a good idea that helps in cold weather as well as improving summer cooling. Depending on who is responsible for maintain the attic or crawlspace insulation, either the board’s chosen contractor or the resident’s contractor will work to identify roof hotspots and take appropriate action.

During winter icing conditions, associations must make difficult choices to handle these leaks. Since no defect is likely, repairmen can only remove the snow and spread salt on the ice which will stop the leaks. Knowing that ice will come again, it is recommended that removal is only performed in limited situations. No decision-making protocol is perfect, so association boards must know the pros and cons of the ice removal decision. The community managers of FirstService Residential are well-versed in ice damming problems and can help your board make the best decisions for your property.