Basement Waterproofing

Waterproofing Contractors in Toronto

If you’ve noticed damp walls, a musty smell, or water pooling in your basement, you’re not alone—and you’re not stuck. For over 30 years, Nusite Group has been the go-to basement waterproofing company in Toronto, helping homeowners across the GTA fix leaky basements and protect their homes from water damage. We know how stressful it can be to deal with water coming in where it shouldn’t, and our goal is to make the solution clear, straightforward, and reliable.

Our certified team provides full-service residential waterproofing tailored to your home’s needs, whether it’s a small foundation crack or a major drainage issue. We offer both interior and exterior waterproofing services, using trusted products from industry leaders like Tremco, Soprema, and W.R. Meadows. From identifying the source of a leaky basement to delivering long-lasting repairs backed by material and labour warranties, we’re here to help you feel confident about your home again. Serving Toronto and the wider GTA, Nusite is committed to making waterproofing stress-free and built to last.

Learn More About Our Waterproofing Services

If you’re searching for reliable basement waterproofing services in Toronto or anywhere in the GTA, Nusite Group is here to help. As experienced, professional waterproofing contractors, we’ve built our reputation on quality work, honest advice, and proven results. Whether you’re dealing with a small basement leak or planning a large-scale exterior solution, we’ll guide you through every step with clear communication and expert recommendations.

As a trusted waterproofing contractor, we offer full interior and exterior waterproofing services in Toronto, backed by strong warranties and over 30 years of experience. We also provide free estimates, so you can get the answers you need without pressure or obligation. Contact us today to schedule your consultation and get started on protecting your home from water damage—for good.

Exterior Waterproofing

When it comes to permanently solving leaks in your basement, exterior waterproofing is often the most effective solution. By addressing water issues at the source—from the outside—this method prevents moisture from ever reaching your foundation walls. At Nusite Group, we specialize in full-service exterior solutions that not only stop water intrusion but also help preserve the structural integrity of your home. If you’re dealing with a damp or wet basement, this approach provides long-term peace of mind.

Our process includes careful excavation, foundation wall inspection, foundation repair if needed, and the application of high-performance waterproof membranes from trusted manufacturers. This type of waterproofing offers homeowners a true barrier against water, reducing the risk of mold, structural damage, and future costly repairs. By choosing to waterproof from the outside, you’re investing in a solution that keeps your basement dry year-round while protecting one of your home’s most critical components—its foundation.

Interior Waterproofing

When water starts making its way into your basement, but exterior access is limited or not practical, interior waterproofing services offer a highly effective alternative. At Nusite Group, we use proven internal waterproofing methods to manage water from the inside—keeping your basement dry and livable, even during heavy rain. One of the most popular solutions we install is a weeping tile system, which channels water away from your foundation and into a sump pump or drainage outlet, preventing it from pooling or causing further damage.

Interior waterproofing is especially useful for finished basements or situations where a full exterior excavation isn’t feasible. For homes with a minor basement leak or small foundation cracks, we also offer professional crack injection repair using high-quality, long-lasting materials. No matter the size of the issue, we’ll design a waterproofing system tailored to your home’s specific needs—keeping your basement dry, functional, and protected from future water problems.

Backwater Valve & Sump Pump Services

Basement flooding is one of the most stressful issues a homeowner can face—but with the right systems in place, it’s completely preventable. At Nusite Group, we help protect homes across Toronto with professional sump pump installation and backwater valve systems designed to keep your basement dry, even during the heaviest storms or sewer backups.

A reliable sump pump is your first line of defense against groundwater accumulation, automatically pumping water away from your home before it can cause damage. We also install backwater valves, which prevent wastewater from flowing back into your home through drains during a municipal sewer overload—a common cause of basement flooding in older Toronto neighborhoods. These upgrades not only help safeguard your home, but may also qualify you for city rebates and insurance savings. Our licensed technicians ensure every installation meets building codes and is tailored to your property’s unique drainage needs.

Window Well Repair & Installation

Poorly functioning or damaged window wells are a common source of leaks in basements—especially during heavy rainfall. As a trusted basement waterproofing company, Nusite Group offers expert window well repair and installation services designed to keep water out of your basement and protect your lower-level living spaces. Whether your existing wells are rusted, clogged, or improperly draining, we can repair or replace them with updated systems that effectively redirect water away from your foundation.

Proper window well installation includes drainage components that connect to either a sump pit or weeping tile system, preventing water buildup that can lead to foundation damage or basement flooding. We use durable materials and ensure each well is sealed correctly against the wall, reducing the chance of future leaks. Whether you’re upgrading old wells or adding them as part of a broader waterproofing project, our team ensures the job is done right—keeping your basement dry and your home protected.

Why Foundation Waterproofing Is Important For Toronto Homes

In a climate like Toronto’s—with frequent freeze-thaw cycles, heavy rain, and aging infrastructure—foundation waterproofing isn’t just a nice-to-have, it’s essential. Small foundation cracks or moisture around your basement wall may not seem urgent at first, but they can quickly lead to serious problems like mold, structural damage, and costly repairs. That’s why so many homeowners in the City of Toronto turn to trusted experts like Nusite Group for long-term basement leak repair and prevention solutions.

Waterproofing your foundation helps keep your basement dry year-round, transforming it from a damp storage area into a safe, comfortable living space. Whether you’re planning to renovate your basement or just want to avoid unexpected flooding, taking steps to waterproof your basement now protects your home’s value and your peace of mind later. From targeted repairs to complete waterproofing systems, we provide solutions that work with Toronto’s unique soil conditions and housing styles.

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Which Waterproofing Method Is Right For Me?

If you’re dealing with a wet basement, choosing the right approach to fix the problem can feel overwhelming. At Nusite Group, we help homeowners make sense of the options by offering expert guidance on the best basement waterproofing solutions for their specific situation. In most cases, exterior waterproofing is the ideal method. It prevents water from ever touching your foundation walls, offering long-term protection and preserving your home’s structural integrity. It’s what we consider true waterproofing.

However, we understand that not every foundation is easily accessible—especially in tightly spaced urban areas. In those cases, interior waterproofing is a practical and effective alternative. Interior systems focus on water management, redirecting moisture away from your basement using drainage systems like weeping tiles and sump pumps. For smaller waterproofing projects, such as minor foundation cracks and leaks, interior crack injection repairs are often a fast and affordable fix. No matter the method, our goal is to deliver a dry, healthy basement that suits your home, budget, and timeline.

Basement Waterproofing FAQ

Signs That Your Foundation Needs Waterproofing

There are several telltale signs that your foundation may need waterproofing, and catching them early can help you avoid costly damage. Common indicators include water stains or damp spots on your basement wall, pooling water on the floor, musty odors, mold growth, and peeling paint or efflorescence (a white, chalky residue) on masonry surfaces. Cracks in the foundation—either horizontal or vertical—are also a red flag, as they can allow water to seep through over time.

If you notice any of these issues, it’s time to consult a professional waterproofing contractor. Water intrusion may seem minor at first but can lead to structural weakening, reduced property value, and unhealthy indoor air quality. An experienced contractor can assess whether your home needs basement waterproofing services such as exterior membrane installation, interior drainage systems, or foundation crack repair. For homeowners in Toronto and the GTA, timely intervention is key to protecting your property from long-term moisture damage.

Do you have references and can I see some of your past projects?

Yes. We will provide them upon request.

What Is the Difference Between Interior and Exterior Basement Waterproofing?

The main difference between interior and exterior basement waterproofing lies in how each method addresses water intrusion. Exterior waterproofing is a preventative approach that stops water before it reaches your foundation walls. This typically involves excavating around the home, repairing any cracks, and applying a waterproof membrane or coating to the outside of the foundation. It may also include installing weeping tile or drainage systems to direct water away from the home entirely. It’s considered the most thorough and long-lasting method, especially for homes with ongoing water issues.

Interior waterproofing, on the other hand, is a water management strategy that deals with water after it enters your basement. This method may include the installation of interior drainage systems, sump pumps, and vapor barriers. It’s often the go-to solution when exterior excavation isn’t feasible—such as in densely built urban areas of Toronto. Both methods are effective, but the right choice depends on the source of the water and accessibility of your foundation. A qualified waterproofing contractor can help you determine which approach suits your home best.

Why is Water Coming Up Through the Basement Floor?

Water coming up through your basement floor is usually a sign of hydrostatic pressure—when groundwater surrounding your foundation builds up and forces moisture through cracks or porous concrete. This issue is common in areas with high water tables or poor drainage, and it often gets worse after heavy rain or snowmelt. In Toronto, aging infrastructure and clay soil can contribute to these problems, especially in older homes that lack modern drainage systems.

To stop water from entering through the floor, basement waterproofing solutions such as a weeping tile system and sump pump installation are highly effective. These systems relieve the pressure under your foundation and channel water away safely. If minor cracks are the source, interior crack injection may be a quick fix, but for recurring problems, a more comprehensive waterproofing system is usually required. The key is identifying the source of the water and designing a solution that addresses the root cause, not just the symptoms.

What is the Best Waterproofing Method for Basements?

The best waterproofing method for basements depends on your home’s structure, the severity of the water issue, and your budget. Generally speaking, exterior waterproofing is considered the gold standard because it creates a physical barrier that keeps water away from your foundation. This method includes excavation, crack repair, waterproof membrane installation, and exterior drainage systems. It’s ideal for long-term protection and is especially effective for homes experiencing persistent wet basement issues.

However, in situations where exterior access is limited or impractical—such as tight property lines or finished landscaping—interior waterproofing services offer a reliable alternative. These methods focus on managing water once it enters the basement, using drainage channels, sump pumps, and vapor barriers. For minor foundation cracks or occasional leaks, targeted interior repairs like crack injection may be sufficient. Consulting with a trusted waterproofing contractor in the GTA can help you determine the most effective approach for your specific basement conditions.

Is Basement Waterproofing Worth It?

Yes, basement waterproofing is absolutely worth it—both as a preventative measure and a solution for existing water issues. A dry basement protects your home’s structural integrity, improves indoor air quality, and increases usable living space. It also helps prevent serious problems like mold growth, rotting wood, and foundation damage. In a city like Toronto, where older homes and fluctuating weather patterns often lead to wet basement conditions, waterproofing is a smart investment that adds long-term value to your property.

Additionally, basement waterproofing can help reduce insurance claims and may qualify you for rebates or incentives—such as those offered by the City of Toronto for installing backwater valves or sump pumps. Whether you’re planning a renovation or just want peace of mind, professional basement waterproofing services help ensure your home stays dry, healthy, and protected for years to come.