How much does a full foundation waterproofing and parging job cost for a 1960s home in Scarborough?

A full exterior foundation waterproofing and parging project on a 1960s Scarborough home typically costs $8,000 to $18,000, depending on the home's perimeter length, foundation depth, soil conditions, accessibility, and whether the weeping tile needs replacement. This is one of the more significant foundation investments a homeowner can make, but for Scarborough's 1960s housing stock, it is often one of the most necessary.

Most Scarborough homes built in the 1960s have poured concrete or concrete block foundations with original parging that is now 60-plus years old and well past its service life. These homes were typically built with minimal dampproofing — often just a single coat of tar or asphalt emulsion that has long since cracked and failed. The original clay weeping tile is frequently collapsed, clogged with roots, or crushed. Scarborough sits on heavy clay soil that holds moisture against foundation walls for extended periods and exerts lateral pressure as it swells and shrinks with seasonal moisture changes. All of this means a 1960s Scarborough home often needs the full treatment: excavation, waterproofing, new weeping tile, and re-parging.

Breaking down the costs: Exterior excavation to expose the foundation walls from grade down to the footing runs $3,000 to $6,000 depending on depth (typically 5 to 7 feet for a 1960s Scarborough bungalow or split-level) and accessibility. If the home has a deck, porch, walkway, or landscaping along the foundation, removal and replacement add to the cost. Once the walls are exposed, the contractor cleans the surface, repairs any cracks (epoxy or polyurethane injection at $300 to $800 per crack), and applies a liquid rubber waterproofing membrane at $8 to $15 per square foot. A dimpled drainage membrane (HDPE dimpled board) is installed over the waterproofing at $3 to $6 per square foot — this is the gold standard for GTA exterior waterproofing, creating an air gap that channels water down to the weeping tile instead of pressing against the membrane.

New 4-inch perforated PVC weeping tile replaces the original clay tile, bedded in clear gravel and wrapped in filter fabric to prevent clogging. This runs $30 to $60 per linear foot installed. The excavation is then backfilled with clean granular fill (not the original clay), and the grade is sloped away from the foundation at a minimum 6-inch drop over the first 6 feet, as required by the Ontario Building Code Section 9.14.

The above-grade portion of the foundation then gets re-parging — old parging stripped, surface prepped with bonding agent, and new polymer-modified parging applied in two coats. For a typical Scarborough bungalow with 100 to 150 square feet of exposed foundation, parging adds $1,500 to $3,000 to the project.

The Ontario Building Code (Section 9.13.2) requires all below-grade foundation walls to have dampproofing or waterproofing on the exterior surface. While you are not legally required to retrofit an existing home, performing this work when excavation is already happening is far more cost-effective than doing it later. All contractors must carry WSIB coverage, and if any electrical work is involved (relocating an exterior outlet, for instance), an ESA-Licensed Electrical Contractor must handle that portion.

Seasonal timing matters. Excavation and waterproofing work is best scheduled from May through October when the ground is not frozen. Spring is peak season for waterproofing contractors in Scarborough — booking early or scheduling for summer can improve both pricing and contractor availability. Get a minimum of three detailed written quotes that specify excavation depth, membrane type, weeping tile replacement, backfill material, and parging specifications. Toronto Parging can match you with experienced waterproofing and parging contractors through the Toronto Construction Network.