Foundations project guide

Foundations contractors cost and hiring guide

Footings, stem walls, slabs, piers and basement walls formed and poured to the plans and inspected before backfill.

Key facts

Foundations numbers you can check

Rules and figures that come up in nearly every foundations quote, with the public source for each one.

Fact	What it says	Source
Minimum footing depth	Exterior footings must sit at least 12 inches below undisturbed ground surface under IRC R403.1.4.	International Residential Code, Chapter 4 FoundationsAs of September 2026
Frost protection	IRC R403.1.4.1 requires footings to extend below the frost line unless the design uses frost-protected shallow foundations or solid rock.	International Residential Code, Chapter 4 FoundationsAs of September 2026
Frost-protected shallow option	IRC R403.3 lets heated-buildup footings stay above the frost line when insulation is added to code.	International Residential Code, Chapter 4 FoundationsAs of September 2026

Project guide

Hiring foundations contractors

Foundation contractors build the part of the structure that carries everything above it into the ground: spread footings below frost depth, stem walls or basement walls, monolithic and slab-on-grade foundations, and pier or grade beam systems where soils are poor. The work follows the stamped plans and the geotechnical report, and it is inspected at fixed points, usually the open footing trench with rebar in place before the pour, then again before the slab and before backfill. Frost depth sets the footing bottom, from about twelve inches in the Gulf states to four feet or more across the northern tier. Waterproofing or dampproofing, a footing drain and free-draining backfill are what keep a basement dry, and they are cheapest to do right while the wall is still exposed.

GradeLine lists 3,223 foundations contractors.Compare their work and equipment, then confirm availability and service area before requesting a quote.

Listed businesses are based in Auburn Hills, Milwaukee, Cygnet, though most crews travel well beyond their home city.

What foundations work costs

Slab-on-grade foundations typically run $6 to $14 per square foot of footprint, crawl spaces $8 to $20, and full basements $30 to $100 or more depending on depth, wall height and waterproofing. A foundation for a typical 2,000 square foot house therefore ranges from roughly $12,000 for a simple slab to $60,000 or more for a basement in a cold climate.

Ranges are national and approximate; regional labor rates, material prices and site conditions move them in both directions.

Common projects

Monolithic and slab-on-grade foundations for houses, garages and shops
Crawl space and full basement foundations with footings, walls, drainage and waterproofing
Pier, grade beam, helical and drilled pier foundations, plus foundation repair and underpinning

What affects a quote

Foundation type, footprint, wall height and the rebar and concrete volume the plans call for
Excavation depth, soil bearing capacity, groundwater and any over-excavation or engineered fill
Formwork, pumping, waterproofing, footing drains, anchor bolts and backfill

Foundations FAQ

What does foundations work cost?

What should I share when requesting a foundations estimate?

Send the stamped structural plans, the soil report, the survey with corner stakes and elevations, the truck access route, and the framing start date the foundation has to be ready for.

What can change the cost of foundations work?

The main cost items are foundation type, footprint, wall height and the rebar and concrete volume the plans call for; excavation depth, soil bearing capacity, groundwater and any over-excavation or engineered fill; formwork, pumping, waterproofing, footing drains, anchor bolts and backfill. A site visit helps the crew see which ones apply.

Do foundations projects need permits?

Foundation work is always covered by the building permit, and the footing inspection has to pass before any concrete is placed. Many jurisdictions also require a foundation survey or as-built before framing to confirm setbacks, and engineered systems need the engineer's letter of observation.