Basement Waterproofing Cost in London (2026)
Average cost in London
$3,000 – $18,000
$70 – $250 per sq ft
In London, the average is $8,959 and most projects cost between $3,000 and $18,000, or about $70 – $250 per sq ft. Prices are before tax and based on 11 sources.
Cost Breakdown
ItemizedExcavation, installation, and site restoration
65%
Membranes, weeping tiles, gravel, and sealants
25%
Sump pumps, basins, and backwater valves
5%
City of London plumbing and building permits
5%
HST at 13%
📋What's Included
ScopeTypically Includes
- Interior drain tile system
- Sump pump installation
- Vapor barrier
- Crack injection sealing
- Labor
Typically Excludes
- Exterior excavation waterproofing
- Foundation repair
- Mold remediation
- Dehumidifier
- Landscaping restoration
Based on interior waterproofing for a standard 800-1,000 sq ft basement.
🧮Estimate your project
LiveYour estimate in London
Likely range $4,032 – $18,000
- Labor65%$5,823
- Materials25%$2,240
- Equipment & Systems5%$448
- Permits & Inspections5%$448
Interior sealant
$8,959
Interior drainage / weeping tile
$14,334
Exterior excavation
$21,502
Calibrated to 11 researched sources for London. Before tax. Real quotes vary with site conditions.
📈Price Momentum
Year-over-year~1 year ago
$8,598
Today
$8,959
Basement Waterproofing in London is ↑ 4.2% compared to roughly a year ago — about $361 more on the average project.
Comparison derived from the year-over-year change rate, not a month-by-month price index. We don't store historical snapshots yet — when we do, this will become a real time series.
🏢Top Waterproofing Contractors in London
Verified providersBasement Waterproofing London
32 Covent Market Pl, London, ON N6A 1E2, Canada
45 reviews
Advanced Basement Systems
199 Exeter Rd Unit E, London, ON N6L 1A4, Canada
191 reviews
Classic Basement Waterproofing London
229 Grand Ave, London, ON N6C 1M6, Canada
24 reviews
Provider data sourced from public business directories. Ratings and reviews are public and may change. LookupCost is not affiliated with listed providers.
💬What People Actually Paid
Community❓Common Questions
Yes, the City of London's Basement Flooding Grant Program covers up to 90% of eligible costs for specific measures. Homeowners can receive up to $1,800 for backwater valves, $4,000 for sump pump systems with weeping tile disconnection, and $1,400 for battery backups.
In 2026, interior waterproofing in London typically costs $70–$150 per linear foot ($3,000–$8,000 total), while exterior waterproofing ranges from $150–$250+ per linear foot ($8,000–$18,000+ total) due to the extensive excavation required.
Yes, a City of London plumbing permit is mandatory for installing backwater valves or tying a sump pump into the municipal system. These permits typically cost between $150 and $300 and are required to qualify for municipal grants.
For a single foundation crack, London contractors typically charge between $650 and $1,100 for interior epoxy or polyurethane injection. If exterior excavation is required for the repair, costs can rise to $1,800–$2,400 per crack.
📊Our Methodology
How we collect dataAggregated from 5+ verified web sources and cost databases
Licensed contractor estimates and regional cost guides
Government construction and labor statistics
Community-reported project costs and reviews
Last data collection: 3 weeks ago. Updates run weekly. All costs in CAD.
About this data
Cost figures are estimates synthesized from public market data using AI research and refreshed regularly. Real project costs vary by scope, materials, contractor, and site conditions. Always get verified quotes from licensed contractors for your specific project.
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