Foundation & basement cost calculators
Free, no-signup foundation, basement waterproofing and below-grade calculators for homeowners and buyers — foundation repair & piering cost, waterproofing per linear foot, crawl-space encapsulation & vapor barrier, French drain & sump pump, concrete slab and footing cubic yards, and budget, contingency, ROI & loan math. Every tool works on the prices you enter and shows its formula, a worked example and a reference table.
Foundation Repair
What foundation repair costs on your line items and prices: full repair estimate, piering & underpinning, crack injection per foot, and bowing-wall carbon-fiber straps or anchors.
All Foundation Repair tools →Basement Waterproofing
Budget waterproofing from the prices you enter: basement waterproofing per linear foot, interior drain tile, exterior excavation & membrane, wall sealer gallons, and an egress window.
All Basement Waterproofing tools →Crawl Space
The crawl-space project math: encapsulation liner area & cost, vapor-barrier rolls from area & overlap, dehumidifier sizing tier, and crawl-space wall insulation.
All Crawl Space tools →Drainage & Sump
Keep water off the foundation: exterior French drain per foot with gravel take-off, sump pump install line items, yard/surface drainage, and buried downspout extensions.
All Drainage & Sump tools →Concrete & Slabs
Below-grade concrete quantities: slab leveling (mudjacking vs polyjacking), concrete slab cubic yards, footing volume, and a concrete driveway — all on your prices.
All Concrete & Slabs tools →Budget, Financing & ROI
Plan the money: repair budget allocator by %, a contingency planner, a cost-per-square-foot normalizer, an illustrative loan-payment tool, and a repair ROI / value-protection ratio.
All Budget, Financing & ROI tools →Foundation Repair
Basement Waterproofing
Crawl Space
Drainage & Sump
Concrete & Slabs
Budget, Financing & ROI
Built for the whole below-grade project — and to stay correct forever
BasementCalcs gathers the calculations homeowners and buyers reach for across a whole below-grade project — foundation repair, basement waterproofing, crawl space, drainage, and concrete flatwork, plus budget & ROI — in one focused hub, in US units, without signup, with transparent formulas. Every tool shows not just the answer but the underlying formula, a worked example and a reference table.
Because the tools rest on timeless project math (piers = affected length ÷ spacing; wall area = perimeter × height; concrete volume = area × thickness ÷ 27 cubic yards; material quantity = area ÷ coverage × (1 + waste); cost = quantity × your unit price) and stable conventions (27 cubic feet in a cubic yard; typical pier spacing ~6–8 ft; carbon-fiber strap spacing ~4 ft; vapor-barrier overlap ~6–12 in; drain-tile slope ~1%), they stay correct with no maintenance — no material price list, no labor-rate database, no regional cost index, no live loan rate. Cost tools use the prices you enter from your own quotes and bills. More at Sources & formulas, Methodology and About. Planning an interior basement finish or remodel instead? That is a different job — see the sibling site RenovationCalcs.
Estimates, not bids. Every cost result is a planning estimate — get itemized written quotes from licensed contractors; have a licensed structural or geotechnical engineer assess foundation movement, cracks, bowing walls and drainage before repair; structural, excavation and electrical work needs licensed pros and a permit; the financing and ROI tools are illustrative math on your figures, not financial advice, and home value protected or added is never guaranteed. No mold, radon or air-quality health claims.