★★★★★
LF Builders delivered a stunning patio. My backyard looks like it's from a magazine! Skilled, friendly, and highly recommended!Pary Gero Google Review
Dry basements, protected foundations
Waterproofing That Fixes the Cause, Not the Symptom
Serving Toronto and every city and town within 50 miles. Free on-site estimates, itemized quotes, and 50+ years behind every job.
- ★★★★★ 4.9 on Google & HomeStars
- 50+ years in business
- 30,000+ projects completed
- Fully insured & WSIB covered
- Free estimates
Dry basements, protected foundations
What we do
Water in the basement is never random, it's grading, gutters, a crack, or hydrostatic pressure, and usually a couple of those working together. We diagnose before we dig, because the right fix for one house is overkill for the next.
From exterior membrane and weeping tile excavations to interior drainage systems, crack injections and sump pump installations, we've kept GTA basements dry for five decades. And because we also finish basements, we know exactly what a waterproofing job has to protect.
Recent projects include an exterior membrane and weeping-tile replacement on a 1960s Richmond Hill side-split, crack injections in a Newmarket Glenway basement before finishing, and a full drainage correction on a Vaughan home that three other companies had quoted excavation for, it was a grading fix.
Diagnosis before digging
We find where water actually enters, grading, gutters, cracks or water table, and quote the fix that matches, not the biggest one.
Exterior & interior systems
Full exterior membrane and weeping tile, or interior drainage and sump systems where excavation isn't practical.
Crack injection
Polyurethane injection for poured-concrete cracks, permanent, fast and far cheaper than excavation when it's the right fix.
The whole water path
Eavestrough, downspouts, grading and window wells, we handle the above-ground causes too, because most 'foundation leaks' start at a clogged gutter.
Water problems we fix every week
If any of these sound familiar, you're exactly who we built this page for.
- Vertical foundation cracks leaking after heavy rain
- Musty basements with white mineral staining (efflorescence) on the walls
- Window wells that fill up and seep
- Sump pumps that run constantly or not at all
- Negative grading and short downspouts dumping roof water at the foundation
No surprises
How the project runs
Inspection & diagnosis
We inspect inside and out, find the entry points, and explain what's happening in plain language.
Right-sized quote
Itemized options, sometimes it's a $600 crack injection, sometimes it's full excavation. You'll know why either way.
The fix
Excavation and membrane, interior system, injection, or drainage corrections, done clean and inspected.
Water management
Grading, downspout extensions and window wells corrected so the system never gets overwhelmed.
Warranty
Our waterproofing work is warrantied, and we're still here 50 years on to honour it.
Typical timelines
| Project | On-site time |
|---|---|
| Crack injection | Half a day |
| Sump pump install | 1 day |
| Interior drainage system | 2–4 days |
| Exterior excavation & membrane | 3–7 days |
Our work
Recent projects
In their words
What homeowners say
★★★★★
Garrett did an amazing job on my porch. Great price, punctual, and no hidden costs. Couldn't be happier with the result!Eric Cohen Google Review
★★★★★
Well-organized and professional company. They exceeded our expectations and stuck to the budget. Highly recommend them!Julian A Google Review
★★★★★
Great work from start to finish! Punctual, friendly, and professional. I'd hire them again without hesitation!Val Google Review
★★★★★
Garrett at LF Builders was the most knowledgeable. The job was executed flawlessly, and the team exceeded my expectations!Private User HomeStars Review
★★★★★
LF Builders fixed our patio in just 4 days. The team was fast, efficient, and creative. We'll definitely call them again!Leon in Toronto HomeStars Review
Frequently asked questions
How much does basement waterproofing cost?
Crack injections run $450–$900 per crack. Interior drainage systems typically run $90–$150 per linear foot, and full exterior excavation with membrane runs $150–$300 per linear foot depending on depth and access. We quote after diagnosing, never before.
Interior or exterior waterproofing, which is better?
Exterior is the gold standard because it stops water before it touches the wall, but it needs excavation access. Interior systems manage water that gets in and are often the practical choice for finished landscapes or tight lot lines. We install both and recommend based on your actual situation.
My basement only leaks in spring. Is that serious?
Seasonal leaks mean water finds you when the ground is saturated, the gap is there year-round. It's usually a cheaper fix now than after a finished basement or a freeze-thaw cycle widens it.
Do you fix the grading and gutters too?
Yes, and we check them first, because a surprising number of 'foundation problems' are really roof-water problems. Extending downspouts and regrading is the cheapest waterproofing there is.
Is the work guaranteed?
Yes, our waterproofing carries a written warranty. Ask us about it at the estimate, and check our HomeStars reviews for how we handle callbacks.
Can you waterproof before finishing my basement?
That's the ideal order, and we do both, waterproof first, then finish. One contractor, one warranty, no finger-pointing.
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What homeowners are saying about waterproofing
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Close to home
Where we work
If you're within 50 miles of Toronto, you're in our service area. Crews are on the road daily across the GTA and beyond, including:
- Toronto
- North York
- Scarborough
- Etobicoke
- Newmarket
- Aurora
- Richmond Hill
- Vaughan
- Markham
- King City
- Stouffville
- Bradford
- East Gwillimbury
- Georgina
- Caledon
- Mississauga
- Brampton
- Oakville
- Burlington
- Milton
- Pickering
- Ajax
- Whitby
- Oshawa
Related services
Let's build it together
Ready to talk about your waterproofing project?
Free on-site estimate, an itemized quote, and a straight answer about whether the job is worth doing.
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