Montreal’s clay soils and freeze-thaw cycles put real stress on foundations. Acting early avoids far costlier repairs.

Spot the warning signs

  • Horizontal or stair-step cracks in basement walls.
  • Water marks, dampness, or whitish efflorescence.
  • Sloping floors or doors that stick.
  • A persistent musty smell.

Require the RBQ licence

As with roofing, the contractor must hold a Régie du bâtiment du Québec (RBQ) licence and current insurance. Ask for recent references.

Waterproofing: interior or exterior

Exterior waterproofing (excavation) treats the cause; interior solutions (drains, membranes) manage water that gets in. A good contractor explains the trade-offs.

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Frequently asked questions

Is a crack always serious?

Thin vertical cracks are often harmless. Horizontal or widening cracks deserve a prompt inspection.

Does home insurance cover the work?

It depends on the cause. Document everything and check your policy; some backups and water damage are covered, but wear and tear is not.