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Waterproofing · Montreal, QCLast reviewed October 2026

7 Best Waterproofing Companies in Montreal, QC (2026)

TenBestFind ranks 7 waterproofing contractors in Montreal, QC. Each company was checked against the criteria set out under How we chose. Lists name up to ten companies, and this one stops at 7 because only 7 met them. The list was last reviewed on October 21, 2026.

Systèmes Sous-sol Québec leads the Montreal list with 4.8 stars from 1,295 Google reviews, followed by Sous-Sol Confort at 4.9 from 378. Seven foundation and drain specialists cleared our bar of 4.5 stars, 50 reviews and a real staffed office, and several work from Laval, the West Island or the South Shore.

7 companies reviewed7 rankedHow We Rank

The Ranking

Our top 7 waterproofing contractors in Montreal

Montreal basements deal with freeze and thaw cycles, high water tables near the river and plenty of older plex buildings with stone or block foundations. Most leaks are fixed with a French drain (drain français), crack injection, an exterior membrane or a sump pit. In Quebec, contractors doing this work need a Régie du bâtiment du Québec (RBQ) licence, and you can check any number for free at rbq.gouv.qc.ca before you sign.

Showing 7 of 7
  1. 01

    Best for a drain français and sump system with a transferable warranty

    Systèmes Sous-sol Québec

    4.8(1300 Google reviews)
    Best forMontreal homeowners wanting a drain français and sump system with a lifetime transferable warranty
    In business19 years
    WarrantyTransferable lifetime warranty on perimeter drainage systems; written warranty with free evaluation
    EmergencyNot listed

    Why we picked them

    Rated 4.8 from 1,295 Google reviews, and as the exclusive Quebec Basement Systems dealer since 2007 it offers a transferable lifetime drain warranty.

    What we like

    • Exclusive Quebec dealer of Basement Systems and Foundation Supportworks products
    • Transferable lifetime drain warranty
    • RBQ licence listed, plus financing up to 120 months

    Things to consider

    • Laval base, weekday hours, no emergency service stated and the pump installation scope is unclear.
    Key details
    Best for
    Montreal homeowners wanting a drain français and sump system with a lifetime transferable warranty
    Service area
    Montreal
    Address
    2990 Boul. le Corbusier, Laval, QC
    Years in business
    19 years
    Warranty
    Transferable lifetime warranty on perimeter drainage systems; written warranty with free evaluation
    Financing
    Available
    Credentials
    RBQ contractor licence
  2. 02

    Best for interior drains, sump pumps and crack repair on the island

    Sous-Sol Confort

    4.9(380 Google reviews)
    Best forInterior drains, sump pumps and crack repair on the island
    In businessNot listed
    WarrantyCompany states a written, transferable warranty on its services, including 25 years transferable on Power Beam wall supports. Confirm the term for your system.
    EmergencyNot listed

    Why we picked them

    4.9 from 378 Google reviews, a published RBQ licence and a transferable written warranty.

    What we like

    • Publishes its RBQ licence number on its own site
    • Transferable written warranty, 25 years on wall supports
    • Reviewers praise tidy, punctual crews

    Things to consider

    • Based in Laval, about 25 to 30 km from downtown, and the site is French only.
    Key details
    Best for
    Interior drains, sump pumps and crack repair on the island
    Service area
    Montreal
    Address
    4430 Boulevard Dagenais Ouest, Laval
    Warranty
    Company states a written, transferable warranty on its services, including 25 years transferable on Power Beam wall supports. Confirm the term for your system.
    Financing
    Available
    Credentials
    RBQ contractor licence
  3. 03

    Best for leaking foundation cracks and French drains

    Akton Injection

    4.9(537 Google reviews)
    Best forLeaking foundation cracks and French drains on the island and nearby suburbs
    In business50 years
    WarrantyWarranty on the work, with terms depending on the service completed; the website publishes no number of years.
    EmergencyNot listed

    Why we picked them

    4.9 from 532 Google reviews, and a family-owned crack injection specialist since 1976.

    What we like

    • Family-owned since 1976 and focused on crack injection
    • Crews praised for punctual, tidy work
    • RBQ licence number published on its site

    Things to consider

    • Weekday-only hours with no emergency line, and no published warranty years.
    Key details
    Best for
    Leaking foundation cracks and French drains on the island and nearby suburbs
    Service area
    Montreal
    Address
    19420 B Ave Clark-Graham, Baie-d'Urfé
    Years in business
    50 years
    Warranty
    Warranty on the work, with terms depending on the service completed; the website publishes no number of years.
    Financing
    Available
    Credentials
    RBQ licence (certified foundation specialist)
  4. 04

    Best for cracks, settlement and seepage together

    Alerte Fissure Inc

    4.8(167 Google reviews)
    Best forHomes with foundation cracks, settlement and water seepage together
    In businessNot listed
    Warranty10 years against water coming through foundation walls where a drain and membrane were installed; 25 years on pile stability; 5 years on crack repair from the outside; 1 year on temporary interior crack injection (as stated on the company FAQ).
    EmergencyNot listed

    Why we picked them

    4.8 from 167 Google reviews, a Pointe-aux-Trembles piling specialist with a 10 year membrane and drain warranty.

    What we like

    • Delta-MS membrane tied to a new French drain
    • Stated 10 year warranty against wall seepage
    • Reviewers praise foreman Michel and Martin for clear explanations

    Things to consider

    • Piling is the core trade, so most reviews describe structural jobs rather than drain-only work.
    Key details
    Best for
    Homes with foundation cracks, settlement and water seepage together
    Service area
    Montreal
    Address
    4005 Boulevard Saint-Jean-Baptiste, Pointe-aux-Trembles
    Warranty
    10 years against water coming through foundation walls where a drain and membrane were installed; 25 years on pile stability; 5 years on crack repair from the outside; 1 year on temporary interior crack injection (as stated on the company FAQ).
    Credentials
    APCHQ certified
  5. 05

    Best for a leaking or widening foundation crack

    Yvon Aubert Construction Inc

    5.0(93 Google reviews)
    Best forLeaking or widening foundation cracks
    In businessNot listed
    WarrantyThe site promises guaranteed work and shows APCHQ warranty logos; the length and transferability of the warranty are not stated.
    EmergencyNot listed

    Why we picked them

    5.0 from 91 Google reviews from a South Shore crack injection specialist whose site lists Montreal first among its service areas.

    What we like

    • Reviewers report on-schedule jobs with no surprise charges
    • Found a quick slot ahead of rain for a leaking crack
    • Shows APCHQ warranty logos and claims 40 years of experience

    Things to consider

    • Crack repair only; the site describes no exterior membrane, French drain or sump work.
    Key details
    Best for
    Leaking or widening foundation cracks
    Service area
    Montreal
    Address
    1320 Rue Labadie #106, Longueuil, QC
    Warranty
    The site promises guaranteed work and shows APCHQ warranty logos; the length and transferability of the warranty are not stated.
    Credentials
    APCHQ Garantie Rénovation (logo shown on website)
  6. 06

    Best for West Island and Vaudreuil homeowners

    Solage Solide

    4.7(60 Google reviews)
    Best forWest Island and Vaudreuil homeowners needing crack repair or a French drain
    In businessNot listed
    WarrantyTransferable warranty on the work, described on the company website; the number of years is not stated, so ask for it in writing.
    EmergencyNot listed

    Why we picked them

    4.7 from 60 Google reviews, with a stated RBQ licence and per-municipality permit guides.

    What we like

    • Publishes permit and city contact guides for 30-plus municipalities
    • States its RBQ licence number
    • Reviewers praise itemised, clearly explained quotes

    Things to consider

    • Warranty length is unpublished and the base is off the island.
    Key details
    Best for
    West Island and Vaudreuil homeowners needing crack repair or a French drain
    Service area
    Montreal
    Address
    384 Grand Boulevard, L'Île-Perrot, QC
    Warranty
    Transferable warranty on the work, described on the company website; the number of years is not stated, so ask for it in writing.
    Credentials
    RBQ contractor licence
  7. 07

    Best for cracks, French drains and waterproofing with a 15 year warranty

    Les Fondations Nouvelle Génération Inc.

    4.9(140 Google reviews)
    Best forFoundation cracks, French drains and waterproofing across the island
    In business10 years
    Warranty15 years on foundation waterproofing with French drains and on exterior crack repairs
    EmergencyNot listed

    Why we picked them

    4.9 from 140 Google reviews, RBQ licensed, with a 15 year warranty and a named owner.

    What we like

    • 15 year warranty on waterproofing with French drains and exterior cracks
    • RBQ licence number published on every page
    • Reports Consumer Choice Award wins from 2023 to 2026

    Things to consider

    • Based about 60 km west in Saint-Zotique, with weekday-only Google hours and no emergency service.
    Key details
    Best for
    Foundation cracks, French drains and waterproofing across the island
    Service area
    Montreal
    Address
    123 Rue des Frênes, Saint-Zotique
    Years in business
    10 years
    Warranty
    15 years on foundation waterproofing with French drains and on exterior crack repairs
    Credentials
    RBQ contractor licence

Side by Side

Compare the top waterproofing contractors in Montreal

Ranking position reflects our editorial review, not customer ratings.

Editorial comparison of the 7 ranked companies. Customer ratings, where shown, come from the source named on each company profile.
RankCompanyBest forKey servicesService areaGoogle ratingEmergencyProfile
01Systèmes Sous-sol QuébecMontreal homeowners wanting a drain français and sump system with a lifetime transferable warrantyMontreal4.8(1300)Not listedView
02Sous-Sol ConfortInterior drains, sump pumps and crack repair on the islandMontreal4.9(380)Not listedView
03Akton InjectionLeaking foundation cracks and French drains on the island and nearby suburbsMontreal4.9(537)Not listedView
04Alerte Fissure IncHomes with foundation cracks, settlement and water seepage togetherMontreal4.8(167)Not listedView
05Yvon Aubert Construction IncLeaking or widening foundation cracksMontreal5.0(93)Not listedView
06Solage SolideWest Island and Vaudreuil homeowners needing crack repair or a French drainMontreal4.7(60)Not listedView
07Les Fondations Nouvelle Génération Inc.Foundation cracks, French drains and waterproofing across the islandMontreal4.9(140)Not listedView

Coverage

Waterproofing companies serving Montreal and nearby areas

Most companies in this ranking work across Quebec and the surrounding suburbs. Coverage and travel fees vary, so confirm your address is inside the service area before scheduling.

  • Montreal

Service coverage across Montreal. Individual company areas are listed on each profile.

Methodology

How we chose the best waterproofing contractors in Montreal

Companies are listed in the order Google returned them for basement waterproofing searches in Montreal on October 21, 2026. Each had at least 4.5 stars, 50 Google reviews, an operating status, a working website, a street address and a Montreal service area named on its own site. Where a firm is based off the island, the listing gives the base and the distance. Template sites, tower-floor offices with no sign of staff and general renovation firms were left out. Only seven firms qualified, so the list has seven entries rather than ten.

Read our full ranking methodology
Evaluated7
Ranked7

Hiring

How to choose a waterproofing contractor in Montreal

  1. Verify insurance and credentials

    Ask for a current certificate of insurance and confirm registration or licensing with the authority that issues it, not with the company.

  2. Ask for a written estimate

    Scope, materials, removal, disposal and who pulls the permit should all be named on the page rather than agreed on the doorstep.

  3. Compare multiple quotes

    Two or three bids on the same scope. A number far below the others usually means something has been left out of it.

  4. Understand the warranty

    Separate the manufacturer's warranty on materials from the company's own warranty on the work, and get both in writing.

  5. Ask who performs the work

    Find out whether the crew are employees or subcontractors, and who supervises them on the day.

  6. Check recent local projects

    Ask for addresses or photographs of comparable jobs finished nearby in the last year or two.

  7. Avoid high-pressure sales

    A discount that expires today, or a knock on the door after a storm, is a reason to slow down rather than sign.

  8. Get everything in writing

    Change orders, timeline and payment schedule included, before the first payment changes hands.

Questions to ask before hiring

0 of 10 asked

Red flags

  • No verifiable local business address or registration
  • Pressure to sign on the first visit
  • A demand for full payment up front
  • An offer to cover or waive your insurance deductible
  • Refusal to put warranty terms in writing
  • A quote that will not itemize scope

Keep Going

Related home services in Montreal

FAQ

Waterproofing companies in Montreal FAQs

Do waterproofing contractors need a licence in Quebec?

Yes. Contractors doing construction work in Quebec need a Régie du bâtiment du Québec (RBQ) licence with the right subcategory. You can check any licence number for free at rbq.gouv.qc.ca, and you should also ask for proof of insurance and CNESST clearance before work starts.

How much does a French drain cost in Montreal?

None of the companies here publishes a fixed price, because cost depends on the length of the foundation, access and whether the work is inside or outside. Get at least two written, itemized quotes, and ask whether the warranty is transferable to a new owner, since many Montreal buyers ask for that at resale.

Why do Montreal basements leak after the spring thaw?

Frozen ground and snowmelt push water against foundation walls, and repeated freeze and thaw cycles open cracks and clog old drains. A cracked wall is often fixed with injection from inside, while a failed or missing drain français usually needs excavation. A good contractor will tell you which one you have before quoting.

Editorial Record

About this ranking

Originally published
October 2026
Last reviewed
October 2026
Companies evaluated
7

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