Basement Renovations
Basement Waterproofing Before Finishing in Toronto and the GTA
The best time to stop water is before there is anything nice in the basement for it to ruin.
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We are not a foundation repair company. We are the people who finish basements, which is exactly why we take moisture seriously. Every basement project starts with a moisture assessment: staining or white powder on the walls, damp corners, past water entry, how the lot drains and how often the sump runs. What we find decides what happens before framing.
Often the fix is simple and outside: regrading soil away from the house, extending downspouts, sealing a crack. Sometimes it means interior drainage, a new sump with battery backup, or a backwater valve on the main drain. If the foundation needs major exterior excavation or structural repair, we bring in a specialist and coordinate their work into the project.
What is included
Waterproofing before finishing by Lintel
Moisture assessment
A visual check of walls, floor, sump and exterior grading before design.
Exterior fixes
Regrading and downspout extensions to move water away from the foundation.
Crack repair
Sealing of minor foundation cracks, with specialist repair coordinated where needed.
Sump and backup
New or upgraded sump pumps, including battery backup for power outages.
Backwater valve
A backwater valve on the main drain to help protect against sewer backup during heavy rain.
Below-grade wall assembly
Insulation and framing details that keep moisture away from finished surfaces.
Before you build
What to plan for
Start outside
A surprising amount of basement water comes from grading and downspouts. Fixing them is cheap compared to interior systems, so we always check outside first.
Check for subsidies
Some GTA municipalities have offered programs that help with backwater valves and related work. Programs change, so it is worth checking with your city before work starts.
FAQ
Waterproofing before finishing: common questions
Should I waterproof my basement before finishing it?
If there is any sign of water, yes. Even in a dry basement, we recommend a sump with battery backup and a backwater valve where appropriate, because they are much easier to add before the space is finished.
What is the difference between interior and exterior waterproofing?
Exterior waterproofing seals the outside of the foundation and usually means excavating around the house. Interior systems manage water that gets in, directing it to a sump. Which one fits depends on the house and the problem.
What does a backwater valve do?
It lets waste flow out of the house but closes if the municipal sewer backs up, which helps keep sewage out of the basement during heavy storms.
More basement renovations
Where we build
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Start your waterproofing before finishing project
Tell us a little about your project. We will call within one business day to arrange a site visit, then show you a design in 3D and a fixed price before anything is built.
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