What they are, how to avoid them and what to do if you have one
Ice dams in Massachusetts are an ongoing nuisance and cause extensive water damage to homes and structures. Recent record-breaking winters throughout the country have caused damage to tens of thousands of homes as a result of ice damning.
What is it and how does it work:
An ice dam occurs when snow accumulates on the slanted roof of a house with inadequate insulation. Heat conducted through the insufficient insulation and warm air from the attic bypasses warms the roof and melts the snow on those areas of the roof that are above living spaces, but does not melt the snow on roof overhangs. Meltwater flows down the roof, under the blanket of snow, onto the eave and into the gutter, where colder conditions on the overhang cause it to freeze. Eventually, ice accumulates along the eave and in the gutter. Snow that melts later cannot drain properly through the ice on the eave and in the gutter, resulting in leaks to the roof space resulting in damaged ceilings, walls, roof structure and insulation.
Primary Prevention Measures:
- Insulation – Installing additional insulation on the attic floor will reduce the temperature in the attic. Keep in mind once you reach the area’s optimal R-Value (a measure of the insulating value of a material), a further increase in the amount of insulation will not show an appreciable decrease in heat loss.
- Weather stripping – And/or insulation can also be installed on attic stairways or hatchways and on attic floor-mounted louvers for whole house ventilation fans. Review manufacturer specifications on the fans or recessed lighting fixtures if the additional insulation will adversely affect their performance.
- Ventilation – Without an adequate amount of ventilation, heat will build up despite the amount of insulation. Ventilation will also remove water vapor that can condense in the attic and result in dry rot and rust. If the house roof has an overhang, or soffit, vents can be added to these soffit areas. A ridge vent can also be added. This vent is mounted along the length of the peak of the roof. The cold outside air that enters the soffit vents rises along the inside of the roof and exits through the ridge vent. This action cools the roof and removes moisture at the same time.
Frequently Asked Questions (Courtesy of Travelers Insurance: https://www.travelers.com/prepare-prevent/home-property/winter-weather/ice-dams.aspx)
Q. How do I know if there is too much snow and ice on my roof?
A. The answer depends on a number of factors, including the roof type, construction technique, and age and condition of the structure. As a rule of thumb, if there is more than a foot of heavy, wet snow and ice on your roof, you should try to have it removed.
Q. How should I remove the snow and ice that has accumulated from my roof?
A. If you have a flat roof that is easily reached from an interior stairway, you may want to shovel the roof. Remember to put safety first any time you are on a roof, especially one that is covered in snow and ice. If you have any doubt, leave it to the professionals.
If you have a sloped roof, it may be possible to remove the snow and ice using a roof rake, a long-handled tool designed specifically for this purpose. Stand on the ground and pull as much of the snow off the eaves as you can safely reach. It is not necessary to remove all the snow; removing the first three to four feet of snow closest to the gutters will help alleviate these issues.
Q. What if I can’t reach the roof at all?
A. Many homebuilders, landscaping and roofing contractors, and property maintenance companies will remove snow and ice from roofs. Before hiring a contractor, Travelers encourages you to check references. Always be sure your contractor is insured and bonded.
We do not recommend using a ladder in snowy and icy conditions. This can be extremely dangerous and is best left to professionals.
Q. Will my insurance company pay to have snow and ice removed from my roof?
A. Each claim is unique, and coverage and claim decisions always require an expert analysis by a licensed Claim professional. However, property owners are generally responsible for preventive maintenance. Keep in mind that the cost of snow removal is likely to be considerably smaller than the cost of roof damage or interior property damage caused by water leaks.
Q. I already have an ice dam on my roof. What should I do about it?
A. If you can reach the roof safely, try to knock the ice dam off with a roof rake, or cut a channel through the ice to allow standing water to drain. If you cannot reach the roof safely, consider hiring a contractor to remove it.
Another method is to fill a nylon stocking with calcium chloride ice melt and place it vertically across the ice dam so that it melts a channel through the dam. If you try this method, make sure you can safely position the ice melt on your roof, and make sure to use calcium chloride, not rock salt. Rock salt will damage your roof. Also be aware that shrubbery and plantings near the gutter or downspout may be damaged.
Q. I have an ice dam. How can I tell if it has caused damage inside my home?
A. Look for water stains or moisture in the attic or around the tops of exterior walls on the top floor. Just because an ice dam is present does not necessarily mean water has penetrated the roof membrane. However, it is always best to remove ice dams before they have the opportunity to cause damage.
Q. I have giant icicles hanging off my gutters. What should I do?
A. Look carefully at where the ice is. If the icicles are confined to the gutters and there is no water trapped behind them, this does not indicate the presence of an ice dam. However, large icicles can pose a danger to people when they fall off. Try to safely knock the icicles off from the ground, making sure not to stand directly beneath them. If you cannot reach them safely from the ground, consider hiring a contractor to help.
Q. What else can I do to protect my home?
A. An easy way to help snow and ice drain off your roof is to make sure the area around your downspouts is clear. This will make it possible for your gutters to drain when snow does melt. It will also help prevent flooding when the snow and ice melts.
Q. How do I keep this from happening again next year?
A. Using a roof rake to clear the first three to four feet of snow from your roof immediately after each winter storm is an effective approach to preventing ice dams from forming.
Ultimately, the best prevention for ice dams is to eliminate the conditions that make it possible for them to form in the first place. Making sure your attic is well insulated will help prevent the melting-and-freezing cycle that causes ice dams to form.
Also, when replacing a roof, make sure to install a water membrane underneath the shingles. This acts as an extra barrier that helps prevent water from seeping inside the building.
Q. What should I do if there is damage to my home?
A. Call Aronson Insurance: 781.444.3050