Ontario Bathroom Renovation 2026: Permits, Waterproofing and Cost Ranges

Bathrooms deliver 70-80% cost recovery at resale in GTA markets. Here’s what to know before starting.

Permit required when:

  • Moving or adding plumbing drain/supply lines
  • Adding a bathroom in a new location
  • Altering load-bearing walls
  • Adding a new electrical circuit

Cosmetic work (new tile, vanity, fixtures in existing locations) typically no permit required.

GTA cost ranges (2026):

  • Cosmetic refresh (toilet, vanity, mirror, light, paint): $3,000-$7,000
  • Full gut, updated fixtures, keeping plumbing locations: $15,000-$28,000
  • Full gut with relocated plumbing, walk-in shower, radiant floor: $28,000-$55,000
  • Primary ensuite with custom tile shower, soaker tub, double vanity: $45,000-$80,000

Waterproofing: OBC requires waterproof membrane in all wet areas. Best practice for custom tile showers: liquid-applied membrane (Schluter KERDI, Laticrete Hydro Ban). Missing waterproofing is the leading cause of bathroom structural damage.

Fan ventilation: Must exhaust to exterior (not attic). Minimum 50 CFM intermittent. Humidity-sensing fans prevent moisture damage without relying on occupant behaviour.

Bathroom contractor referrals at home.renovation.reviews