Call Now 1.800.265.1914

Firestopping 101

April 21, 2022

Firestopping: what it is, why it's important and what to look for in a good system installer.

When commercial or multi-tenant buildings are constructed, they have built-in fire compartments – a series of “boxes” that keep fire and smoke from spreading. If one unit catches fire, it offers protection to the others, giving occupants enough time to call the fire department and get out safely.

“As a fire rages, smoke travels, and you can't outrun smoke,” says Barclay Myers, Firestop Group at Great Northern Insulation. “Those walls keep people alive. Ever looked at a row of townhouses and noticed a bump on the roof of each unit? That's the fire-rated wall. It has to go past the building envelope, which is why it sticks out. If one side catches fire, that wall is what slows down the spread.”

When electrical and plumbing components are installed in fire separations, however, the holes they create diminish that protective ability. That’s where firestopping systems come in: high-tech filler materials are installed to maintain the integrity of those walls. Anywhere there are pipes, cables, wiring or joints, those materials seal the gaps. And firestopping doesn't cost a lot if you do it right. But if you don't, it can cost a great deal – in retrofit expenses, fines, damage, and in the worst-case scenario, human life.

What should you look for in a firestopping provider?

Expertise. Firestopping is one of the smallest expenses in construction, but it can wind up being the biggest obstacle. If it's not done properly from the outset, it can keep you from passing occupancy. If you’re forced to redo it after a building is complete, the cost can be astronomical. You want it done right the first time.

“Having a qualified team that really knows their stuff can mean the difference between passing and failing an inspection – and between life and death,” says Barclay. “Since firestopping isn’t a recognized trade, anyone can do it, but not everyone is an expert. If you don’t have that, it can really cost you down the line.”

Materials knowledge. How well do the installers understand the materials they’re working with? Do they have the right materials on hand? When there’s such a wide selection of options for different applications, it can get complicated. “It’s pretty easy to squirt goop in the hole,” says Barclay, “But understanding why you’re using a certain material can make an important difference. GNI’s firestopping team is factory-trained and authorized by major materials manufacturers, so you get the best possible solution.”

Comprehensive service offerings. A general contractor may be able to install the materials, but working with a bigger company that specializes in firestopping can make the process a lot smoother and more turnkey – especially if they have made an investment in digital capabilities and experience working with inspectors and other trades.

GNI delivers on all aspects of fireproofing

The core firestopping team has 100+ years of experience between them, with unparalleled knowledge smaller players don’t have. The proof is in their pass rate: they have never failed an inspection. Their one-stop-shop offering includes:

  • Firestopping system selection
  • Engineering judgments
  • Total materials procurement
  • Professional installation
  • Coordination with other trades and local authorities
  • Talking with building inspectors
  • Fully insured and bondable
  • Digital process controls like electronic estimating and field documentation
  • Service for all industrial commercial and institutional sectors

“Instead of going with a generalist contractor, there’s a lot of value in going with a specialist team,” says Barclay. “Especially when you think of what the consequences of getting it wrong can be”

Learn more about GNI firestopping systems – and get it right the first time.

Having a qualified team that really knows firestopping can mean the difference between passing and failing an inspection.

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!