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If You Don't Have Ice, It Doesn't Mean You Have Good Insulation

December 17, 2015

Many homes in Canada suffer from "ice dams" during snowy, icy winters. And not all contractors understand "ice dams" well enough to explain to the homeowner. The basics are the important part. Heat escapes from inside the home, warms parts of the roof, and the snow melts in those warm parts. At this point its water that trickles down the various parts of the roof, and when it hits cold parts, it freezes. The freezing ice accumulates and eventually forms an "ice dam". Ice damming can seriously damage the roof, the shingles, and the interior ceilings of a home. The antidote, of course, is good insulation, and when properly installed, it will effectively stop ice damming and the associated damages. However, the absence of ice damming does not necessarily mean that the roof and attic have good insulation. It only means that the insulation envelope is currently adequate and stable. As such, the potential for ice damming could be looming. The truth is, it's not just about good insulation. It's about a complete "system" that incorporates airtightness, ventilation and good insulation all together. Ice damming or not, the air barrier in a home is what keeps indoor air from escaping, and leaking air is one of the biggest challenges for an insulation contractor. In many cases, energy efficiency in a home is not related to a roofing issue, but rather to an insulation issue, where good insulation could be the remedy. Experienced insulation contractors can quickly isolate and evaluate the extent of air leakage in a roof or attic. And while good insulation may be part of the solution, the essential thing is to seal the space tight. This is most effectively solved with Spray Polyurethane Foam, an application that completely seals roofing vents, HVAC ducts, and even recessed lighting fixtures. Good insulation is still important, but nothing beats sealing up every little hole, crack and crevice. When sealing is complete, a reliable contractor will recommend a good insulation product to suit the requirements of the project. Here, fiberglass batts, fiberglass blown insulation, and Spray Polyurethane Foam (SPF) are all possible options. Today, more and more insulation contractors are suggesting SPF as the better option overall. In fact, for cost effectiveness, some of the best installations combine SPF with one of the fibreless products in a "hybrid" install. Once again, good insulation is only one component of a complete job. Proper ventilation in attics and roof cavities is a must, and any good contractor will insist on it. In particular, preventing ice dams has as much to do with proper ventilation as it does with good insulation. But importantly, even a well-ventilated space will not perform without sealing the space completely. The best outcomes will result when sealing, ventilation and insulation are all working together. As it is, Spray Polyurethane Foam is more than just a good insulation product. A professional installation will ensure the highest possible R-Value; the most effective air barrier/vapor barrier; and an insulation project that is fully code-compliant. The best news for the homeowner: big cost savings on heating bills during the winter, and air conditioning bills in the summer.

Western Ontario

935 Keyes Drive
Woodstock, Ontario
Canada N4V 1C3

Phone: 1-800-265-1914

Fax: (519) 539-7946
TOLL FREE: 1-800-265-1914

Southwestern Ontario

7035 Industrial Drive
Comber, Ontario
Canada N0P 1J0

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Muskoka, Haliburton, Northern Ontario

1027 Elwell Park Road
Gravenhurst, Ontario
Canada P1P 1R1

TOLL FREE: 1-800-265-1914

Central Ontario

29 Ferndale Industrial Drive
Barrie, Ontario
Canada L4N 9V5

TOLL FREE: 1-800-265-1914

GTA East

103 North Port Road
Port Perry, Ontario
Canada L9L 1B2

TOLL FREE: 1-800-265-1914

GTA & South Central Ontario

450 Industrial Dr,
Toronto (Milton), Ontario
Canada L9T 5A6

TOLL FREE: 1-800-265-1914

Eastern Ontario

1035 Moodie Dr #1,
Nepean, ON
K2R 1H4

TOLL FREE: 1-800-265-1914


259 Campbell Street
Sarnia Ontario
Canada, N7T 2H3

TOLL FREE: 1-800-265-1914

Niagara Region

6260 Don Murie St
Niagara Falls, ON
L2G 0B4

TOLL FREE: 1-800-265-1914


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From reputation to responsiveness, HomeStars consistently ranks Great Northern Insulation at better than 95% for customer satisfaction. Thanks to everyone for the great ratings! 

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For the second year in a row, HomeStars consistently ranks Great Northern Insulation at better than 95% for customer satisfaction. Thank you again to everyone!

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For the third year in a row, HomeStars ranked Great Northern Insulation at better than 95% for customer satisfaction.

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WALLTITE® ECO™ is a high-performance system, professionally installed by certified and approved specialists. Its C.C.M.C. approved (Canadian Construction Materials Centre) - with product quality guaranteed - and with installation by highly trained experts with the technical know-how to do the job right, the first time.

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For the ultimate in high performance spray foam insulation, Insulthane® Extreme is the professional choice for residential, commercial, and industrial application. With improved thermal performance over other products, Insulthane® Extreme has an exceptionally low Global Warming Potential (GWP). Considered environmentally friendly, this next generation spray foam insulation is non-ozone depleting, and exceeds specifications of other HFC product alternatives.


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3MTM energy-saving products are designed to keep warm air in, and cold air out, while keeping energy bills down. Products optimize energy efficiency in buildings and homes; improve indoor environment for occupants; and effect the reduction of seasonal energy costs. 3M products are authorized for LEED credits (Leadership in Energy/Environmental Design).


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Mike Holmes and his son Mike Jr. (MJ) convert MJ’s bachelor bungalow into a two-storey home for MJ and his girlfriend Lisa. Choosing the newest materials and build techniques, the father and son team follow Mike’s famous motto – “Make it right.” The show can be watched on HGTV and DIY Network.


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