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GNI Expands into Ottawa as Part of Amalgamation with Insultech Insulation Specialists Inc.

October 23, 2018

great northern insulation amalgamation with insultech ottawagreat northern insulation division with insultech insulation specialists inc ottawa

OTTAWA, ON, October 23, 2018 – Great Northern Insulation (GNI), Ontario’s largest full service insulation contractor, today announced its amalgamation with Insultech Insulation Specialists Inc. (Insultech), an award-winning Ottawa insulation contractor. The expansion officially marks the seventh location that GNI will operate out of, and adds 25 more employees to the more than 315 currently employed by the company.

Founded in 1980 by two Canadian entrepreneurs, GNI offers products and services that promote comfort, energy efficiency, durability and sustainability in the building industry. In 2016, the company started operating under Mill Street & Co., a diversified management company that ranked No. 3 in the Canadian Business 2018 Startup 50 awards for Canada’s Top New Growth Companies.

“We are really excited to introduce Insultech Insulation Specialists as our newest division,” said Matt Mulligan, VP of GNI. “The Ottawa team already shares our core values, and has built a solid foundation of employee safety and exceeding customer expectations. Our combined years are going to make a big impact on promoting further sustainability and growth in the building industry.”

Founded by James Dunning, Insultech has serviced Ottawa since 1999. The division will offer the same products and services offered by GNI, and will service all of Eastern Ontario.

“We cannot wait to take our customer experience to a new level with Great Northern Insulation,” said James Dunning, President and CEO of Insultech. “As their newest division, Ottawa can expect an even greater range of products and services that will make homes and buildings more comfortable, lower energy bills, and improve the energy efficiency of buildings across every sector.”

As part of the expansion, GNI is currently hiring insulation installers at all seven of their locations. This includes Woodstock, Comber, Milton, Barrie, Port Perry, Gravenhurst, and Ottawa.


Great Northern Insulation is a leading insulation contractor in Canada with seven branches across Ontario and more than 315 employees. Founded in 1980 in Woodstock, Ontario, GNI has been hired to renovate and construct hundreds of thousands of residential, commercial, industrial and agricultural properties. For more information, please visit www.gni.ca

Contact Information:
Matt Mulligan


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.

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