Waterproofing, Dampproofing & Sealants — Quick Reference

Waterproofing vs. Dampproofing

System	Resists	DFT	Use When
Sheet membrane	Hydrostatic	40–60 mil	WT at/above footing; clay/silt; sensitive spaces
Fluid-applied	Hydrostatic	60–80 mil	Same — seamless, no laps
Dampproofing	Capillary	10–15 mil	WT >600 mm below footing; granular; drain tile OK

PM + geotechnical engineer decide based on geotech report. Cannot be changed in field without written authorization.

Parameter	Requirement
Concrete cure	≥7 days (28 preferred)
Side lap	≥75 mm
End lap	≥150 mm
Termination	150–200 mm above grade, mech. bar + sealant
Min substrate temp	5°C (for priming)
Voids >6 mm	Fill with non-shrink grout before membrane

Apply bottom-up. Steel-roll every lap. No air pockets.

Method	Application
100% visual	All membranes — before protection board (HOLD POINT)
Flood test	Horizontal: 50–75 mm water, 24–72 hrs
ELD spark test	Exposed membranes — detects pinholes
ELD low-voltage	After flood test — locates breaches to 25 mm

Torch-applied: Hot work permit + fire watch with extinguisher during and 60 min after. Propane 3 m from work area.
Excavation >1.2 m: Shoring/sloping/trench box mandatory (O. Reg. 213/91 s.222–242).
Confined space: Atmospheric testing, buddy system, rescue plan required (O. Reg. 632/05).
Heritage foundations: Structural engineer assessment before any remediation work. Never excavate beside heritage foundations without site-specific work plan.
No backfill until: Superintendent inspection complete + manufacturer pre-cover acceptance signed. This is a HOLD POINT.

Cold membrane: Below 10°C, warm self-adhered membrane with heat gun to activate adhesive. Cold membrane = poor bond.
Photograph everything before protection board goes on — min 50 photos per wall. Once buried, membrane is gone forever.
Church basements: Full waterproofing (not dampproofing) mandatory for all below-grade mechanical rooms regardless of water table.
Heritage renovations: Monitor interior humidity for 12 months before specifying system. Spring thaw is the true test.