Foundation crack repair cost in Montreal (2026 prices)

Prices documented by Pietro Di Benedetto, President of Sous-Sols Experts Inc. RBQ 5668-8765-01. 500+ projects completed since 2013.

2026 price overview for the Greater Montreal area. Polyurethane injection for a leaking vertical crack: $400 to $700 per crack. Structural crack (horizontal or stair-step) with reinforcement: $2,500 to $8,000. Complete wall rehabilitation with excavation, SOPREMA membrane, and new French drain: $12,000 to $30,000. The on-site inspection is free and produces the exact price for your situation.

Why do prices vary so much?

Foundation crack repair cost in Montreal varies by a factor of 30 depending on crack type and the scope of the fix. A thin vertical crack that leaks calls for a few hours of work at $400 to $700. A structural crack in a leaning block wall calls for soil stabilization, wall reinforcement, and new waterproofing for tens of thousands of dollars. Five variables move the price: crack type, site access, required excavation depth, soil quality, and work urgency. A contractor who quotes a crack over the phone is giving a catalog price, not a real one. See our complete guide on types of foundation cracks for the underlying triage rubric.

Polyurethane injection: $400 to $700 per crack

Polyurethane injection is the standard method for repairing a leaking vertical crack. Polyurethane is a flexible resin that reacts with water in the crack, expands to fill voids behind the wall, and cures into a rubbery seal that resists seasonal micro-movements. In Montreal in 2026, the typical price runs $400 to $700 per crack for a standard 8-foot residential wall, written warranty included (typically 5 or 10 years). Price rises to $1,000 to $1,500 for: a crack over 8 feet tall, a crack crossing a window corner, multiple cracks on the same wall, or difficult access (tight crawl space, low ceiling, equipment carry). Price rarely drops below $400, the threshold where travel, certified labour, and professional Sika product cost is not covered. See our crack injection page for the technical details.

Structural crack with reinforcement: $2,500 to $8,000

A structural crack (horizontal anywhere on the wall, stair-step in a block wall, or vertical with visible widening through the seasons) does not heal with simple injection. The method depends on the diagnosis: stainless steel anchors through the wall for stabilization, interior reinforced concrete buttresses, or carbon fibre strip reinforcement applied to the inside face. Typical 2026 price runs $2,500 to $8,000 depending on extent. Specifically: a single horizontal crack with steel anchors, $2,500 to $4,000; a wall cracked across multiple blocks with carbon fibre reinforcement, $3,500 to $6,000; a wall section requiring interior buttresses, $5,000 to $8,000. These repairs generally require a prior evaluation by a structural engineer ($500 to $1,200) before a contractor proposes a fixed-price quote. Sous-Sols Experts works with a network of Quebec engineers for files that require it.

Complete exterior rehabilitation: $12,000 to $30,000

Complete exterior rehabilitation of a foundation wall with excavation, new SOPREMA waterproofing membrane, and new French drain is the most expensive project. It is also the most durable: a foundation rehabilitated to current standards with membrane under 25-year material warranty is protected for 25 years and beyond. Price runs $12,000 to $30,000 for a standard Montreal residential home in 2026. Main variables: linear footage to excavate (one side = $12,000 to $18,000; three sides = $22,000 to $30,000; four sides rarely necessary for residential foundations); depth (a standard 7-foot basement = bottom of range; a 9-foot basement with deep footing = top of range); landscaping to protect; neighbour proximity (party wall = exterior excavation impossible); and vehicle access (narrow driveway = smaller bobcat, more days on site). See our foundation repair and waterproofing page.

New French drain: $7,000 to $20,000

New French drain installation, often paired with exterior waterproofing while the trench is open, costs $7,000 to $20,000 depending on the perimeter to cover. For a drain installed alone (without redoing exterior membrane) on one side of the home, count $7,000 to $12,000. For a drain installed alongside exterior waterproofing on 2-3 sides, count $15,000 to $20,000 for the drain alone (waterproofing is budgeted separately). The drain can also be installed from inside (interior perimeter floor drain) when exterior is not possible: $8,000 to $15,000 depending on linear footage. See our French drain page.

Sump pump and pit: $1,500 to $3,500

Installation of a Zoeller sump pump with properly sized pit and backwater valve costs $1,500 to $3,500 depending on complexity. The bottom of the range applies to pump replacement in an existing functional pit. The top of the range includes excavation to dig a new pit in a finished basement, concrete floor cut and patch, and installation of a secondary backwater valve if the municipality requires it. For zones identified as sewer-backup risk by Montreal, Laval, or South Shore municipalities, the backwater valve is often partially subsidized under municipal connection programs.

What pushes the price up?

Seven variables systematically move a crack repair price upward: (1) restricted site access (narrow driveway, corner lot with inaccessible back wall), (2) excessive foundation depth (beyond 7 feet), (3) party wall with neighbour (exterior excavation impossible, interior required), (4) landscaping to protect and restore (mature hedges, pavers, deck), (5) attached garage blocking one side, (6) proximity of mature trees (roots to manage, drain potentially compromised), and (7) urgency imposed by active flooding or imminent real estate transaction. One of these factors typically adds 10-20% to the base price; several combined can double it. Conversely, a detached home with open lot, shallow foundation, and a single affected wall lands at the bottom of each range.

Are there tax credits or subsidies?

In Quebec in 2026, there is no provincial tax credit specifically dedicated to foundation repair or waterproofing for individuals (the RénoVert credit was abolished in 2019). However, several Greater Montreal municipalities offer partial subsidies for backwater valve installation, particularly in sewer-backup-risk zones: Montreal (RénoPlex program and backwater valve program), Laval (municipal connection program), and several South Shore cities. Subsidies typically cover $200 to $700 per valve installation. For the foundation work itself, home insurance can cover secondary damage (damaged furniture, finish to redo) but almost never covers the foundation repair itself, considered maintenance. Check your policy and keep written and photographic documentation of any water event.

How to get an exact price for your situation?

The ranges above are 2026 averages in the Greater Montreal area for typical residential situations. For an exact price accounting for your home, your crack, and your access, the on-site inspection is necessary. With Sous-Sols Experts, the visit and diagnosis are free. Our team typically arrives within 48 hours, examines the crack and the entire basement, and delivers a written quote within 24 hours. The quote names the exact Sika product, the execution timeline in days, and the warranty terms. No obligation, no sales pressure. Call Pietro at (514) 979-5425 or use the contact form.