How we estimate
Methodology & sources
No black boxes. Here is exactly how each tool works and what it's built on. Cost figures were last calibrated 2026-06-27 and are refreshed roughly annually.
FoundationCompass is built for the United States: all costs are in USD from US national data, and the insurance verdict reflects the standard US HO-3 homeowners policy. The calculators still work anywhere — pick a regional cost level — but figures and coverage rules won't map cleanly to Canada, the UK, or Europe.
Foundation repair cost
We start from national installed price ranges for each repair type, then apply three multipliers:
- Base range — per repair type (crack, slabjacking, piering, bowing wall, replacement).
- Severity — minor (×0.7), moderate (×1.0), severe (×1.55).
- Quantity — number of cracks or piers for per-unit repairs.
- Regional index — a coarse, state-level cost differential (US average = 1.0). It is deliberately approximate.
Output is always a low–high range with a line-item breakdown, never a single false-precise number.
Basement waterproofing cost
Drain-based methods price per linear foot of affected wall; a sump pump and dehumidifier are lump add-ons. The same regional index applies.
Insurance coverage verdict
The verdict tool encodes the standard ISO HO-3 homeowners policy: foundation damage is generally excluded when caused by settling, earth movement, expansive soil, flood, earthquake, tree roots, gradual seepage, poor construction, or wear and tear — and generally covered when caused by a sudden named peril (burst pipe, fire, windstorm, falling tree, vehicle, explosion, ice/snow weight, vandalism). Endorsements (earthquake, flood) and state rules (e.g. Florida's sinkhole mandate) can change the result. It is general information, not a coverage determination.
State data
Per-state pages use a rough regional cost index plus genuinely state-specific facts: dominant soil/ground risk, earthquake exposure, and homeowners-insurance specifics. Cost figures are approximate by design; insurance specifics are general and should be confirmed with your insurer or state Department of Insurance.
Why ranges, not exact numbers
Foundation pricing genuinely swings with access, soil, severity, and contractor. Anyone quoting a single exact number sight-unseen is guessing. We publish ranges so you can recognise a fair quote — and flag one that isn't.
Sources & methodology
- Foundation repair cost data — Angi (national average ≈ $5,000; range ≈ $2,200–$8,100)
- Foundation repair cost & insurance — NerdWallet
- Insurance Information Institute (III) — what homeowners insurance covers
- A licensed structural engineer / foundation contractor in your area — the authoritative source for diagnosis, scope, and a stamped repair plan
Estimates compiled from the sources above and standard cost models — not engineering, professional, insurance, or legal advice, and may not reflect your policy or local prices. See our full methodology and disclaimer.