What's the cost of applying elastomeric coating over parging to prevent future cracking?

Applying an elastomeric coating over existing parging typically costs $3 to $8 per square foot in the GTA, which works out to $500 to $2,000 for a typical home's foundation perimeter with 100 to 200 square feet of exposed parging. Elastomeric coatings are one of the most effective ways to extend the life of existing parging and prevent future cracking from Toronto's punishing freeze-thaw cycles.

Elastomeric coatings are thick, flexible, rubber-like masonry coatings that bridge existing hairline cracks up to 1-2mm and expand and contract with the parging as temperatures swing from -20°C in winter to over 35°C in summer. Unlike regular masonry paint, which forms a thin rigid film that cracks along with the parging, elastomeric coatings remain flexible for years and create a continuous waterproof barrier that keeps moisture out of the parge coat. Since moisture penetration followed by freeze-thaw cycling is the primary mechanism that destroys parging in the GTA — water enters hairline cracks, freezes and expands by 9%, widens the crack, and repeats over 50 times per winter — preventing moisture entry dramatically extends the parging's lifespan.

The cost breaks down into material and labour. Quality elastomeric masonry coating products run $60 to $120 per gallon and cover approximately 75 to 125 square feet per gallon depending on the surface texture and porosity. Two coats are recommended for full protection, so material costs for 150 square feet of foundation run roughly $150 to $400. Professional application adds labour at $3 to $5 per square foot, covering surface cleaning, priming if needed, and two-coat application with proper drying time between coats. For DIY-inclined homeowners, this is one of the few foundation maintenance tasks that is reasonable to tackle yourself — the application is similar to painting, using a thick-nap roller or airless sprayer, and the main requirement is a clean, dry surface and temperatures above 10°C during application and drying.

Critical prerequisites determine whether elastomeric coating is appropriate for your parging. The existing parging must be structurally sound — firmly adhered to the foundation with no hollow-sounding sections, no large cracks wider than 2mm, and no areas of active delamination. Elastomeric coating is a protective and cosmetic treatment, not a structural repair. If your parging has sections that are loose, flaking, crumbling, or bulging away from the wall, those areas need to be removed and re-parged before coating. Applying elastomeric over failing parging is a waste of money — it will peel off along with the parging it is adhered to.

The surface must also be free of efflorescence (white mineral deposits), dirt, mould, and any previous paint that is peeling. A pressure wash followed by thorough drying is the standard prep. If the parging has previously been painted with a non-breathable paint, that old paint should be removed or the elastomeric will not bond properly.

GTA-specific consideration: homes close to Lake Ontario and along busy streets with heavy salt exposure benefit most from elastomeric coating, as it blocks both moisture and salt penetration. For foundation walls along driveways, the coating protects against salt splash damage through the winter months. Elastomeric coatings are available in various colours, so you can match or refresh your home's appearance while adding protection. Toronto Parging can connect you with masonry professionals through the Toronto Construction Network if you need help assessing whether your parging is a good candidate for elastomeric coating.