Snowstorms can be beautiful. Some are a nuisance. But here’s a way to consider some snowstorms as a friend with a message for you.

In the few days following a snowfall, when you are out for a walk, look along the road at the roofs of your home and your neighbors’ homes. Some will still be covered with snow, some will have lost it all, while some will look kind of patchy. A keen observer will notice that the patterns are pretty consistent time after time.

The patterns relate to attic insulation. If your attic has little or no insulation, the snow will disappear quickly. If your attic insulation needs a fix, the pattern will be patchy. If your attic insulation is good, the snow will stay on for a long while (and actually will add insulation to the roof, since snow is an insulator).

The best snowstorm for these observations will be one that drops about 1 inch, without wind. (A blizzard like the one on Jan. 27 makes observations difficult because the wind blows away some snow completely while dumping extra inches in other places.) So, you should get outside after a gentle snowstorm to examine your roof and compare it to the neighbors

If your roofing is asphalt shingles, the snow should stay for days unless the air temperature rises above 32 degrees. If it melts unevenly, make a note of where the bare roofing shows through first. That is likely to be a place where extra heat is escaping from your house into the attic. Remember, heat rises. Go inside and check the following:

• Recessed lighting fixtures that join living spaces to the attic are perhaps the worst culprits for heat loss. They function like straight conduits from your warm world to the outside. The best advice is to replace such lighting — try track lighting next time.


• A leaky seal to the attic entry hatch can be sealed with foam weather stripping.

• Gaps between fiberglass insulation. If the layers of insulation look thick enough, it probably would be best to hire a contractor to blow in a 2-inch layer of cellulose fiber all over the tops of the batts. This will seal up the air movement through the gaps.

• A bathroom or other vent that empties into the attic may have caused mold to build up on the attic ceiling (the roof decking). The vent should be extended to the outside of the attic and likely will require plumbing.

• Icicles that form along the bottom edge of the roof or eaves are another indication of insufficient attic insulation. Icicles, combined with an ice dam at the eaves, can cause leakage between the shingles with water dripping into your ceiling or walls. It is always best to identify and fix the cause of the problem before you have internal damage.

If you have a metal roof and its slope is 45 or more degrees, these observations are difficult because the snow generally slides off quickly. Keep looking, especially after a big snowstorm.

Here are a couple of special cases you may have to deal with:


• If your home has flat roof, you’ll need to get up on the roof. If you feel slushiness under your feet you have a problem. Under almost every flat roof, there is usually a space between the ceiling of the top floor and the roof decking itself. If you cannot get into that space, you’d be wise to cut an entry so that the space can be insulated, preferably by blown-in cellulose.

• If your home has a cathedral ceiling, once again there is a space between ceiling and roof. If it appears to have been insufficiently insulated (by the quick melting of the snow), you have a few difficult choices: You could remove the ceiling and foam the underside of the roof decking, or you could install sheets of foam externally and then re-shingle. However, there are now ceramic paints that can be applied inside to increase the insulating value of the ceiling.

Your observations and efforts will pay dividends by cutting your heating costs and increasing your comfort.

Peter Garrett is a member of Sustain Mid Maine Coalition’s Public Policy Team and a volunteer home energy consultant through SMMC’s Residential Energy Program. Sustain Mid Maine Coalition is a grassroots organization dedicated to improving the quality of life for the people of central Maine. For more information, visit

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