If your basement is leaking right now, the first hour is damage control, not diagnosis.

• Get boxes, electronics and anything fabric up off the floor.
• If water is anywhere near outlets, the furnace or the panel, stay out of the room and call an electrician first.
• Check the floor drain and the sump. A backing-up drain and a seeping wall look identical once there is water on the floor, and they need opposite fixes.
• Photograph everything before you clean up. Your insurer and your contractor both work from what the water did, not from what it looked like after the shop vac.

Then call us. An emergency basement leak is worth a set of eyes even if the water has already stopped, because the path it took is still there.

What we check on the visit.

The cove joint where the floor meets the wall, which is where most wet basement repair calls end up. Cracks in poured walls and the tie-rod holes left by the original forms. Window wells, and whether they drain or hold leaf soup. Outside, the grading and where the downspouts let go. And the question that decides the whole job: is the water coming through the foundation, or backing up through the floor drain? We settle that before anyone quotes you.

Why winter leaks catch people out.

The ground is frozen, so meltwater and rain cannot soak away. It runs along the frost line and finds your wall instead. Toronto's own climate record counts about 65 freeze-thaw cycles a year over the 1971 to 2000 baseline, and every one works at a crack that was fine in August. A basement that stayed dry all summer can leak in February. That is normal, and not a sign you missed something.

What a leaky basement repair costs depends on how the water is getting in and whether the fix is drainage or a crack. We price it in writing after we have seen it, never over the phone.

Call 1-800-675-1055 or book a free estimate below.

The homeowner's guide on this page tells you which cracks matter. This is what we do about them.

How the injection works.

Most foundation crack repair in a poured concrete wall is done from inside, in an afternoon, with nothing dug up. We clean the crack out, fix injection ports down its length, surface-seal between them, then inject polyurethane under pressure from the bottom port up until it appears at the next one. The resin travels the full thickness of the wall and expands against the wet soil behind it, so the seal is made through the concrete rather than painted onto it. Done properly, a basement crack injection outlasts the rest of the wall.

When injection is the whole answer.

A single vertical or diagonal crack in a poured wall that weeps in heavy rain and has not changed since you marked it. That is the ordinary basement crack repair: no drainage, no excavation, no engineer.

When it is not.

Block walls have hollow cores, so there is no solid section to inject and the water gets managed rather than sealed. Horizontal cracks, stair-step patterns through block, a crack with one side sitting proud of the other, or any crack still growing after you have pencilled and dated the ends: those are load questions. They want a structural engineer's drawings before anybody injects anything. Concrete foundation crack repair that ignores why the wall moved only moves the leak somewhere else.

What it costs.

Basement wall crack repair is priced per crack, by length and by what else the wall needs, in writing once we have seen it. If the wall also needs drainage we will say so, before you spend money on injection that cannot be enough on its own.

If water has ever come up through your floor drain, the fix is plumbing rather than waterproofing. A backwater valve stops the city sewer pushing back into the house; a sump pump lifts groundwater out before it reaches your slab.

The City of Toronto helps pay for both.

Toronto's Basement Flooding Protection Subsidy Program pays 80% of the eligible cost of each item, up to that item's own cap, and up to $6,650 per property in total:

• Backwater valve: up to $1,600 each, maximum two
• Sump pump: up to $2,250
• Battery backup for the sump: up to $300
• Severing or capping a pipe: up to $400
• Plumbing assessment: up to $500

One sump pump per property, with a lifetime maximum per type of work. Funding is first come, first served and depends on the City's annual budget, so qualifying is not the same as being paid.

You may qualify if the work is done by a contractor holding the right City of Toronto business licence, and backwater valves need a permit and an inspection. The current rules and the application: Basement Flooding Protection Subsidy Program.

The licence condition is what stalls people, so we take it off your plate: LF Builders coordinates a City-licensed plumber for the subsidy-eligible work and schedules it with the rest of the job. You still apply, and the City still pays you. We are not the licence holder and we do not file your paperwork.

Outside Toronto.

Amounts and conditions change, so check your city's current rules before you buy anything.

• Mississauga: basement flooding prevention rebate, up to $7,500, with sump pump work up to $6,000
• Region of Peel: backwater valve, 60% up to $1,500
• Richmond Hill: backwater valve, up to $1,500
• Halton Region: backwater valve, 50% up to $1,600 for work completed after 15 July 2024, interior valves only, once per property
• Markham: the Private Plumbing Protection Rebate Program, in designated flood-prone areas only

A sump pump installation is worth doing at the same time as any interior drainage: the channel has to discharge somewhere and the pit is already open. And if your area browns out in storms, that is exactly when the pump is needed, which is the argument for the backup.

Call 1-800-675-1055 to talk it through.

Underpinning is how you get a basement with real ceiling height without moving house. We dig out below the existing footings in short alternating sections, pour new footings deeper than the old ones, and let the wall carry on the new bearing. The foundation ends up lower, and the floor drops to match. Nothing is lifted and nothing hangs: each section is supported before the next is opened.

Bench footing is the cheaper alternative.

Instead of going under the footing, we build a concrete bench inward from the wall and lower the floor inside it. It costs less and takes less time, because the original footings are never disturbed. The trade is floor area: the bench takes a foot or so around the perimeter, and it stays visible. Easy on a big basement, not on a narrow one.

Why people do it.

Headroom. A 1930s Toronto basement with six and a half feet of clearance is storage. Take it to eight and it is a family room, an office, or a legal secondary suite that pays part of the mortgage. Basement lowering is the only way to gain that height without touching the rest of the house.

What it involves.

Basement underpinning needs a building permit and a structural engineer's drawings, and the engineer's numbers drive the sequence, the section widths and the pour schedule. Not optional, and not a formality.

Do the waterproofing while the floor is open.

Once the slab is out and the footings are exposed, new weeping tile, a perimeter drainage channel and a sump pit cost a fraction of what they do as a separate job later, and the wall is reachable in a way it never will be again. Finishing a newly lowered basement over old drainage is the expensive mistake in this trade.

If the plan is a suite for family, the federal Multigenerational Home Renovation Tax Credit may apply. It is refundable, and it covers qualifying costs for a self-contained secondary unit so that a senior, or an adult eligible for the disability tax credit, can live with a qualifying relative. Conditions and limits: line 45355, Multigenerational Home Renovation Tax Credit.

Start it in winter.

Drawings, permits and the engineer's schedule take weeks before a shovel moves. Booking the design work in January is how a basement is finished by the time the kids are home in July.

A basement walkout is a new exterior stairwell cut into the grade beside the house, with a proper door at the bottom. It turns a basement into a floor you can reach without crossing the rest of the house: light, air, getting furniture in, and a separate way in and out.

It is permit work from the first shovel: an opening cut in a load-bearing foundation wall, changed grading, and retaining walls and a stair that have to hold back soil and pass inspection. Where the side yard is tight, or the servicing runs along that wall, the walkout may have to go somewhere less convenient than you would like. We find that out before you commit to a design, not after.

The drain at the bottom of the stairs is the whole job.

A walkout stairwell collects every drop of rain and snowmelt that lands in it, directly against a door into your basement. It needs a drain at the bottom, connected and running, with a grate somebody can clear. Get that wrong and the walkout becomes the leak you spend next spring chasing. It is the most common defect we get called out to on a walkout somebody else built.

A separate entrance is also a step toward a legal basement suite.

The entrance is one requirement among several a second unit has to satisfy, along with ceiling height, egress, fire separation and smoke alarms. Which rules apply depends on your municipality and on the house, so the honest sequence is: find out what your basement can legally become, then build the entrance that suits it. A walk up basement built to the wrong standard is expensive to redo.

We quote a basement walkout as one scope, drainage included, so the stairwell and the waterproofing are one contractor's problem rather than two.

Call 1-800-675-1055 or book a free estimate below.