No, the South Shore Does Not Have One Set of Rules for Excavation and French Drains

Foundation repair, French drain, excavation

Marco comes to you in person for every estimate. Reachable 7 days a week, 8 a.m. to 5 p.m.

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No, the South Shore Does Not Have One Set of Rules for Excavation and French Drains

Foundation repair, French drain, excavation

Marco comes to you in person for every estimate. Reachable 7 days a week, 8 a.m. to 5 p.m.

Get your free estimate

Three cities, three centuries of building: foundations that are not the same age

Montréal’s South Shore includes the five cities of the Longueuil agglomeration (Boucherville, Brossard, Longueuil, Saint-Bruno-de-Montarville and Saint-Lambert), which had more than 430,000 residents in 2021. Marco works in Longueuil, Brossard and Saint-Lambert. These cities are not the same age: the seigneury of Longueuil dates back to 1657, Saint-Lambert was officially created in 1857 and Brossard was incorporated in 1958. A foundation, a drain and a bylaw therefore do not tell the same story there.
They do not share the same bylaws either. In Brossard, zoning bylaw REG-485 requires a French drain around every building with a basement, and rebuilding a foundation or a drain goes through a permit. In Longueuil, bylaw CO-2021-1141 requires a retention pit with a pump, backwater valves and an inspection before backfill. This page is a starting point for the region, with detailed pages for Brossard and Longueuil.
Soil matters too. The St. Lawrence Lowland, where the South Shore sits, was covered by the Champlain Sea, which left marine clays behind (The Canadian Encyclopedia). Only a study of your lot tells you what is under your house, but it is one more reason to assess the soil and the water before excavating: read Soil Type and Your Foundation: Why Clay Matters in Quebec. Marco assesses every job himself (RBQ license No. 5775-3246-01).

What changes from one South Shore city to the next

Here is the essentials for each city, with official sources (in French): Brossard’s residential drainage leaflet, its foundation repair permit form no. 30 and Longueuil’s “Travaux de plomberie” technical sheet. This information does not replace the bylaws: confirm your case with your City.

  • Brossard. A French drain must surround every building with a basement, downspouts must discharge water at least 900 mm from the wall, and pump water may not go onto the driveway or straight to the street (bylaw REG-485). The City’s permit form covers rebuilding a foundation and a French drain, and asks in particular for a detailed quote and the contractor’s RBQ or NEQ number.
  • Longueuil. Once the permit is issued, you must contact the inspector: no exterior backfill or interior slab pour without the inspector’s visit. The French drain discharges into a retention pit with a pump, and backwater valves are required and inspected every year (bylaw CO-2021-1141).
  • Boucherville and Saint-Bruno-de-Montarville. These two cities of the agglomeration are not on Marco’s South Shore list. For a project outside his zones, contact him: he will assess whether he can make the trip.

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Crack repair service

The Process

Interior
Marco - Réparation de fondation

Crack repair

Polyurethane injection

We will determine the cause of the cracks

Epoxy injection

Increases the strength of the structure and the concrete

French drain

We will clean, repair or replace your drains if they are no longer working

Exterior
Marco - Réparation de fondation

Crack repair

Membrane installation

3 water-repellent membranes are applied to the foundation wall

Excavation

We dig with high-performance equipment to minimize damage

Say goodbye to leaks

Keeps water from reaching the foundation by draining it to the base of the wall

The South Shore: where we work

Marco serves the South Shore (Longueuil, Brossard, Saint-Lambert), as well as Montréal, Laval, the West Island and Salaberry-de-Valleyfield. We come to you. See also our Montréal and Laval pages.
To talk to Marco before booking, call (438) 763-0737 from 8 a.m. to 5 p.m., every day, or check our Google listing.

Questions about excavation and French drains on the South Shore

Are the drainage rules the same in every South Shore city?

No. Each City has its own bylaws. In Brossard, bylaw REG-485 requires a French drain around every building with a basement and governs downspouts and pump water. In Longueuil, bylaw CO-2021-1141 requires a retention pit with a pump, backwater valves and an inspection before backfill. Always confirm your city’s rules before excavating.

Do I need a permit to rebuild a foundation or a French drain in Brossard or Longueuil?

In Brossard, the City has a foundation repair permit application form (no. 30) that covers, among other things, French drain rebuilding, stabilization work and cracked houses, and asks for a detailed quote. In Longueuil, the City’s technical sheet provides for a permit, then an inspector’s visit before backfill. For your address, confirm with the City.

Does Marco serve Boucherville or Saint-Bruno-de-Montarville?

On the South Shore, Marco serves Longueuil, Brossard and Saint-Lambert. For a project outside his zones, contact him directly: he will assess whether he can make the trip.

Why assess the soil and the water before excavating on the South Shore?

Because the South Shore sits in the St. Lawrence Lowland, where the Champlain Sea left clays behind. According to Espace pour la vie, a dry summer can dry out the clay under a footing and cause settlement. An inspection tells you whether the problem comes from the drain, a crack or the soil before anyone digs.

My Saint-Lambert drain is over 40 years old: when should I worry?

CAA-Québec gives about 40 years as a drain’s normal lifespan. Beyond that, it is time to have it inspected by camera: you then decide between hydro-jet unclogging, repair of one section or full replacement.

Who assesses my foundation on the South Shore, and how do I book?

Marco comes himself for the free estimate. Fill out the form on this page or call (438) 763-0737 between 8 a.m. and 5 p.m., Monday to Sunday. His company holds RBQ license No. 5775-3246-01.

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Marco - Réparation de fondation

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