Waterproofing

We install and restore waterproofing systems where water does the most damage — foundations, below-grade walls, balconies, and wet-area transitions — using membranes and details that meet Ontario site conditions.

Foundation waterproofing membrane applied

What we include

  • Exterior foundation damp-proofing and membranes
  • Below-grade crack injection and patching
  • Balcony and deck liquid-applied systems
  • Shower and wet-area pan preparation
  • Flashing and penetration sealing
  • Drainage board and protection course installation

Stop water before it reaches finished spaces

Moisture intrusion is rarely a single failed product — it is a chain of missed details at corners, penetrations, and transitions. We excavate where needed, prep substrates to manufacturer spec, and lap membranes so water sheds away from the structure.

Our waterproofing work supports broader renovation scopes: basement finishing, balcony restorations, and exterior envelope repairs. Correct sequencing prevents costly tear-outs after drywall and flooring are installed.

Documentation and warranty-ready installs

We follow product data sheets for temperature, primer, and cure times — critical in spring and fall Ontario weather. Photo documentation of substrate prep and membrane laps is available for property records and engineer review.

After completion we walk through maintenance expectations — grading, downspout discharge, and inspection intervals — so building owners know how to protect the investment long term.

Other renovation services

TNS Construction is based in Newmarket, Ontario and delivers multiple trades for homeowners and general contractors across southern Ontario.

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TNS Construction provides free written estimates for renovation work across southern Ontario.

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