Call Now 1.800.265.1914

Waterproofing and Insulating Exterior Basement Walls

March 13, 2017

One of the most prevalent problems in any house is a damp basement. Beyond the uncomfortable environment, damp basements can potentially lead to mold, as well as structural damages. In the majority of situations, this is work best left to the professionals - there's a good deal of building science involved, and therefore problem-solving requires some specific expertise and experience. Where possible, the best solution for a damp basement is to insulate the walls from the exterior. This will virtually eliminate the accumulation of water vapour in the basement. Also, air leakage will be blocked, and insulating performance will be enhanced. While there may be ancillary work involved in waterproofing the basement walls, the insulation will make a major contribution. Because most basements are below grade, the walls present unique challenges when it comes to air movement and moisture collection. In most homes, the challenges are evident both in summer and winter. This is precisely why basement insulation must ensure the maximum in airtightness. Anything short undermines the potential to block air leakage and prevent air moisture. Professional installers agree that spray foam is the best application for foundation walls in the basement. Beyond the excellent insulating performance, this product significantly lowers the risk of moisture accumulation. The installed R-Value of the finished application is unrivalled amongst other products, and the capacity to control air moisture is hard to match product-to-product. For the homeowner, properly damp proofing and insulating the basement provides a number of benefits. To begin with, home comfort is dramatically improved from season to season. As well, energy efficiency is enhanced because the HVAC system is better balanced. And finally, energy usage is reduced, resulting in less costly utility bills for winter heating and summer cooling. Like the attic and roof, basement insulation is best managed professionally. Insulation experts understand which products will work best, and which installation approach will deliver the best return-on-investment. With a comprehensive approach, professional installers will address both thermal insulation and air moisture at one time - a key consideration in the basement space. For the average homeowner, insulating the basement is more than just an esthetic improvement. A well-insulated basement provides energy savings around the year - so much so that the annual savings will offset the original project cost in a few short years. Indeed, homes with foundation walls that are insulated beyond the norm actually have re-sale values also above the norm. In some situations, homeowners may be enticed by the DIY option for insulating a basement. In terms of saving money in the short term, this may prove viable. However in the long term, damp proofing and insulating the foundation walls is definitely worth doing professionally. The project outcomes will be much better, and the overall benefits will be more comprehensive. With basement insulation, it's about creating a "system" that's based on the principles of building science. This exactly why a professional approach is preferred - in order to address the problem areas, and provide appropriate solutions.

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!