Exterior Waterproofing

Nusite Exterior Waterproofing

The best way to keep the basement of your Toronto area home as dry as possible is to have it waterproofed on the exterior. This will address all of the possible water seepage causes, which typically all come from the outside of your home. If proper exterior waterproofing is performed there shouldn’t be any need for interior work in your basement since the water will remain where it belongs, which is on the outside.

Proper exterior waterproofing requires excavating to the bottom of the foundation, or the footing, and replacing the footing and downspout as well as the existing sets of drainage tile and also treating the walls. Some companies may use tar as a waterproofing sealant material on the walls, but since the substance isn’t flexible it often cracks. If the seal cracks then water can once again seep into the house. At Nusite, we use the following process to seal your basement from the exterior:

1 – The earth around compromised foundation walls is excavated and hauled away. The expansive clay is removed and this will ease the pressure on the walls making them less likely to crack. If the tiles can move enough of the water to keep it below the basement floor then a basement likely won’t leak during normal rainfalls. However, if the water rises higher than the floor it will create hydrostatic pressure and it can enter the basement through cracks in the floor and where the wall and floor meet.

1-Exterior Waterproofing Digging


2 – The exposed foundation wall is cleaned and checked for any damage and cracks and the foundation can then be strengthened and repaired. Hydraulic cement is used since it will expand when it cures and it adds strength to the structure. The first of three protective and environmentally-safe layers is a cement-based sealant which closes the pores to harden the concrete as well as fills in hairline cracks.

1-Exterior Waterproofing


3 – The second protective layer is elastomeric waterproofing, which is pliable, polymer-modified asphalt. Elastomeric membranes can heal themselves should new cracks happen to appear. This process will prevent water penetration under pressure whereas tar will just slow down the water. Tar is known to simply damp-proof a foundation while elastomerics actually waterproofs it.

2-Exterior Waterproofing


4 – The third protective layer is a polyethylene-dimpled drainage mat since the material won’t rip. This heavy gauge mat is ideal for protecting the elastomeric membrane. An air gap is created by the dimples and this can channel any moisture to the drain tile without it touching the wall. Some waterproofing companies may use a sheet plastic known as visquine, but it’s easy to tear making it less reliable than a drainage mat. A drainage mat is also designed to halt diffusion. When the level of moisture outside of a home is higher than it is on the inside the moisture can seep through the foundation walls and create humidity in the basement. This seepage can’t occur though if a polyethylene wrap is used and the basement will be drier and less humid.

External Waterproofing Toronto


5 – The next step is to install new footing tile to keep the level of water below the floor of the basement. This keeps the basement both pressure-free and leak-free. New clean-outs are also installed which allows the footing tile to be accessed without digging in case it needs to be snaked or cleaned.

4-Exterior Waterproofing Mat

The downspout lines which separate from and run above the footing tile are inspected to make sure they’re draining properly. If they’re defective then all of the rainwater on the roof will eventually pool around the home’s foundation. If there’s an interior drainage system in place it will typically discharge a sump pump to these downspout lines. When underground lines aren’t working as they should the system will recycle the water. If new spouts are needed river gravel is used as back-fill rather than limestone and the entire trench is filled. Limestone can often limit drainage since it compacts and it can also clog new drain tiles if it turns into cement.


6 – Once the work has been completed we will restore your home’s landscaping to the original condition with fresh topsoil and any shrubbery that had to be moved will be replanted.

Please contact us at Nusite at your convenience for more information regarding our exterior basement waterproofing systems. We’ve been family-run waterproofing business in the Greater Toronto Area since 1979, we are a top rated HOmestars company with an A+ BBBrating,  and offer residents free inspections as well as fully guaranteed and timely work.

Why choose nusite for your next waterproofing project





Customer Testimonials

Interested in working with us? Check out some of our customer testimonials below and find more on Homestars. We are one of the highest rated basement waterproofing companies in Toronto

Mark Lipton - Homestars Review

Basement Waterproofing

Our basement leaked! Of course . . . we bought a 100 year old house! But my office needed to be in the basement permanently. I interviewed 10 different companies until we decided on the Steinbergs and their crew at Nu-Site! They are professional, reliable, courteous, honest, and they really make an effort to communicate with the client about every step of the process.

Sara Jack - Homestars Review

Foundation and Waterproofing Repairs

After several years of chronic leaks, we decided to have our basement waterproofed once and for all. The team over at Nusite was professional, answered my questions during the project and stayed within their quoted price....which is always a concern for me when working with contractors. Great job overall

Joshua Persaud - Yellowpages Review

Basement Waterproofing

Had several cracks in my basement wall and they would leak whenever we had a heavy rain. It started about a year and a half ago and seems to have gotten worse over the past 6 months. I tried having my neighbor seal it, but it started leaking again within a few weeks. Called several waterproofing companies and got several quotes. Finally went with Nusite contractors for the job. They gave a reasonable quote and I liked the guy that came by for the estimate. They stayed within budget and cleaned up before they left. It's been almost 3 months now and it seems to be working great.