Call Now 1.800.265.1914

Exterior Insulation In Residential Homes

February 17, 2017

The basics of insulation dictate that heat will flow from a warm area to a cool area. In wintertime, heat will flow from the warm indoors to the cold outdoors - and that happens through exterior walls of the home. On the flipside, in summertime, outdoor heat will flow into the home. Exterior walls can actually account for 20% of heat transfer in a typical house. And if that sounds like a lot, it is - it translates into wasted energy, wasted heating and cooling, and wasted money. Years ago, residential homes had little or no insulation in the exterior walls. There wasn't much focus on energy consumption, and for the most part, attic insulation did an adequate job in terms of insulating the home. Heat loss in winter was quite substantial, and heat infiltration in summer was quite common. Today, the idea of exterior insulation makes much sense, primarily because preventing heat loss means using less energy, making for reduced utility bills year-round. In a typical residential "building structure", heat transfer will also compromise the effectiveness of any existing insulation. In rectifying this, the home's overall energy efficiency can be improved dramatically with exterior wall insulation. For most homeowners, attics and basements will take preference over other parts of the home when it comes to home insulation. But in fact, insulating the exterior walls is one of the best home-improvement projects in terms of cost-benefit. Done right, exterior wall insulation can be installed over any surface. Here, spray foam insulation has proven to deliver exceptional results. As a high-performance product, spray foam is viewed as an "all-in-one" application that provides an air barrier, vapour barrier, and thermal insulation with a single installation. The more conventional insulation products cannot compare with spray foam, because they suffer from partial air loss and less than optimal moisture control. With spray foam insulation (whether in the attic or in exterior walls), the "building structure" is sealed tight. And because it seals and insulates at one time, spray foam also delivers the most R-Value per inch of any comparable product. All of this translates into measurably improved energy efficiency for the entire home, and reduced energy use around the year. Indeed, the dollar savings over the years will serve to offset the investment that was made in the original project. For professional installers, it's important to recommend the right product and installation for the job. Professionals have the product knowledge and technical know-how to deliver performance results, particularly with spray foam insulation. These products are uniquely different, requiring specialized equipment and substantial installation expertise. Simply put, spray foam isn't suitable as a weekend do-it-yourself undertaking - it's best left in the hands of those with experience. With home insulation, it's not the right time to look for bargains. A reliable insulation contractor will do it right the first time, with installers who are appropriately trained, and with reputable product warrantees. Spray foam professionals install according to the building code, without taking unnecessary construction shortcuts. Their objective is to deliver long term performance.

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

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

Greater Toronto Area

2 Guided Court
Etobicoke, ON
M9V 4K6

TOLL FREE: 1-800-265-1914

GTA East

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

TOLL FREE: 1-800-265-1914

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

Niagara Region

25 Lincoln Ave
St. Catharines, ON
L2P 2C7

TOLL FREE: 1-800-265-1914


Great Northern Insulation - Better Business Bureau Profile.

Homestars Best of 2021 Award

Best of 2021

HomeStars has ranked Great Northern Insulation as a company that goes above and beyond in every aspect of business for the year of 2021.

Homestars Best of 2022 Award

Best of 2022

HomeStars has ranked Great Northern Insulation as a company that goes above and beyond in every aspect of business for the year of 2022.


GNI is the Authorized & Trusted Insulation and Air Sealing Installer for Lowe’s

Trusted for Over 40 Years

Over 40 Years in Business

At GNI, we service your project with the most experienced staff in the industry. Ongoing professional development is an obsession at GNI and we will not compromise at any level to bring to our customers the very best Installers, Sales Representatives, Customer Care Personnel, Field Superintendents, Estimating and Technical Support to your project.

100% Canadian

100% Canadian

Great Northern Insulation is recognized as Canada's largest full-service insulation contractor. GNI is 100% Canadian owned, proudly serving Ontario customers since 1980.

Foam Masters

Do it right the first time
- with foam mastersTM

January, 2021 regulatory phaseout of hydrofluorocarbons (HFCs) with the introduction of WALLTITE CM01. Using hydrofluorolefins (HFOs) with lower global warming potential (GWP) compared to HFCs, WALLTITE CM01 is the next generation of spray foam insulation.



Heatlok® Soya HFOTM leverages Honeywell’s latest Solstice® Liquid Blowing Agent technology. This new hydrofluoroolefin (HFO) blowing agent is the most environmentally conscious blowing agent produced to date, with a zero ozone depletion potential (ODP) and a global warming potential (GWP) of 1, which is more than two orders of magnitude (99.9%) lower than HFCs used in this industry.


3MTM products.
Quality + Performance = Savings

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).

Holmes and Holmes

Holmes and Holmes


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.


Enbridge Incentives

The Home Efficiency Rebate Plus program offers up to $10,000 in home reno rebates – and Great Northern Insulation can pave the way.


Great Northern Insulation proudly abides by a renovation-specific Code of Conduct set by RenoMark™.


We are Verified & Bonded by eRenovate. When you choose to proceed with our services through their platform, you receive the gaurantees set forth through their program.

As Seen on Love It or List It

The GNI crew have been featured installing insulation on Love It or List It - have you seen our logo in an episode?

Climatizer Cellulose


CLIMATIZER PLUS cellulose insulation is manufactured from a minimum of 85% locally-sourced post-consumer recycled newsprint. Non-toxic additives are applied to the uniquely fiberized paper generating a building material with superior thermal and acoustic properties, as well as exceptional resistance to fire, moisture, mould and pests.

Please, enter a valid value

Incorrect values!