Underpinning commonly costs about $3,300-$9,800 per metre in the United States, equivalent to roughly $1,000-$3,000 per linear foot. A typical residential project may total $15,000-$60,000, with excavation depth, foundation condition, engineering requirements, access, and local labor rates driving the quote.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Underpinning per metre | $3,300 | $6,600 | $9,800 | Converted from $1,000-$3,000 per linear foot |
| Underpinning per linear foot | $1,000 | $2,000 | $3,000 | Typical residential foundation work |
| 20-foot foundation run | $20,000 | $40,000 | $60,000 | Excludes major structural repairs or unusual access |
| Engineering and permits | $1,500 | $4,000 | $10,000 | Varies by design complexity and jurisdiction |
Assumptions: U.S. residential work, standard concrete underpinning, normal site access, and no extensive utility relocation.
What underpinning costs per metre for a house foundation
At the low end, straightforward underpinning may cost $3,300-$4,900 per metre ($1,000-$1,500 per linear foot). Average projects often run $4,900-$8,200 per metre ($1,500-$2,500 per linear foot), while difficult work can reach $9,800 per metre or more. These figures are planning ranges, not fixed national rates; contractors may quote by the foot, by the underpinning pit, or as a whole project.
For a typical accessible foundation, budget about $6,600 per metre, or $2,000 per linear foot, before unusual structural repairs. A 10-metre run at that midpoint comes to about $66,000. Some smaller jobs cost less because only a short wall section needs support, but mobilization, engineering, and inspections can make a short run expensive per metre.
Underpinning is usually installed in short, engineered sections rather than by excavating the entire wall at once. The contractor digs beneath existing footings, places concrete or another designed support system, and sequences the work to keep the structure stable. Price assumptions depend on footing depth, soil, wall loading, basement access, and the method specified by the engineer.
How excavation, concrete, and engineering shape the quote
A detailed estimate separates construction labor and materials from design, inspection, and site costs. The ranges below are indicative components for a 20-foot residential run; they are not additional charges to add blindly to a contractor’s total, since some bids include several items together.
| Quote component | Low | Average | High | What changes the price |
|---|---|---|---|---|
| Excavation and concrete | $8,000 | $18,000 | $32,000 | Pit count, depth, concrete volume, and reinforcement |
| Labor and shoring | $6,000 | $14,000 | $25,000 | Crew size, hand digging, confined access, and sequencing |
| Structural engineering | $1,000 | $2,500 | $6,000 | Calculations, drawings, site visits, and revisions |
| Permits and inspections | $300 | $1,200 | $3,500 | Local fees and number of inspection visits |
| Debris removal and restoration | $700 | $2,300 | $7,000 | Soil disposal, slab replacement, and finish repairs |
Labor and excavation are often the largest variable costs, while engineering and permits are essential parts of a safe, permitted project. A quote may also include temporary supports, pumping, drainage changes, or concrete delivery. Check whether each is included, excluded, or treated as an allowance.
For a rough labor calculation, a small crew might spend 80-160 labor hours on a limited residential run. At combined billed rates of $75-$150 per worker-hour, labor alone could represent $6,000-$24,000, although contractors generally price the completed scope rather than bill a simple hourly total.
Why soil depth and foundation length change the metre rate
Length matters, but it does not determine the price by itself. More metres usually require more excavation and concrete, yet per-metre pricing can fall on a longer, uncomplicated job because setup costs are spread across more work. Conversely, a short section under a heavily loaded wall may cost more per metre than a longer, accessible run.
Depth and access can shift the estimate more sharply than the measured length. A footing requiring excavation 2-3 feet below its existing base may be simpler than one needing 5-6 feet of underpinning, groundwater control, or staged support. Deep pits increase digging time, shoring needs, spoil handling, and engineering oversight.
Soil type also affects the method and pace. Stable, dry soil may permit predictable excavation, while loose fill, water-bearing ground, or nearby buried utilities can require additional stabilization and careful hand work. An engineer may specify smaller work bays or a different foundation system where soil conditions or building loads make conventional mass concrete unsuitable.
Scope is another key threshold. A 10-foot repair may require one or more engineered pits, concrete placement, and inspection even though the measured run is short. A 30-foot run may need more total material but offer a lower unit rate if the wall is clear, the basement floor is already removed, and equipment can reach the work area.
What three residential underpinning quotes can look like
These examples illustrate how project details affect totals. The assumed rates include typical construction work but exclude major structural reconstruction, extensive water management, and interior finish upgrades. Actual bids should follow a site inspection and a structural design.
| Example scope | Length and rate | Labor assumption | Estimated total |
|---|---|---|---|
| Accessible corner repair | 8 ft at $1,250 per ft | About 70-90 crew labor hours | $10,000 construction plus $2,000-$4,000 design and fees |
| Typical basement wall | 20 ft at $2,000 per ft | About 140-200 crew labor hours | $40,000 construction plus $3,000-$6,000 design and fees |
| Deep, restricted-access wall | 25 ft at $2,800 per ft | About 220-320 crew labor hours | $70,000 construction plus $5,000-$10,000 design and fees |
The 25-foot example costs more because difficult access and deeper excavation raise both labor time and support requirements. Labor hours here represent combined worker-hours, not the number of hours the building is left under construction. A multi-person crew can accumulate those hours over a shorter calendar period.
For each quote, compare the same measured wall length and the same engineer-approved design. Ask whether pricing includes excavation, concrete, reinforcement, temporary support, debris removal, inspections, and restoration. A lower per-foot figure may omit several of these items, so the total comparable scope is more useful than the headline rate.
How foundation type and access affect the installation price
Traditional mass concrete underpinning is often suitable for shallow, sequential support work where site conditions allow small excavated pits. A contractor may charge about $1,000-$2,500 per linear foot for a relatively conventional job. If excavation is deep, soil is unstable, or the building is difficult to access, the rate can rise to $2,500-$4,000 per foot or more.
Alternative systems can change the price structure rather than simply lower the price. Helical piles or push piers may be considered when loads, soil, or access make conventional underpinning impractical. Their costs are commonly quoted per pier or support point, often around $1,500-$4,000 each for residential work, with engineering and installation details affecting the figure. The number and capacity of supports matter more than a direct per-metre comparison.
Basement underpinning that lowers a floor to gain headroom is a broader project than stabilizing an existing footing. It may require excavation across much of the floor, new slab work, drainage, waterproofing, and utility adjustments. A full basement-lowering project can cost $50,000-$150,000 or more, depending on area and finish level; it should not be priced using a simple foundation-wall metre rate.
Access can add costs when crews must carry soil through a narrow interior route, remove a basement slab, protect finished rooms, or work around plumbing and electrical lines. Depending on the constraint, allow roughly $1,000-$8,000 for added demolition, handling, or protection, with major utility relocation priced separately.
How labor hours and site access set the construction schedule
A small, accessible section may take about 1-2 weeks of active work, while a longer or deeper project can take 3-8 weeks. These ranges describe construction activity and may not include time spent waiting for engineering, permits, inspections, concrete availability, or weather. Sequential excavation also limits how much work can safely happen at once.
Most schedule-related price increases come from extra handling, waiting, or required temporary support rather than calendar duration alone. Contractors may charge for additional mobilization if work is split into multiple visits, or for pumping and protection when groundwater enters the excavation. Ask which conditions trigger a change order and how daily site protection is handled.
Labor pricing depends on local wages and crew composition. A specialist foundation crew may have higher hourly billing rates than general excavation labor, but experience with staged underpinning can reduce avoidable delays. The estimate should state the expected work sequence, crew size or labor allowance, and whether concrete placement and debris hauling are included.
How U.S. location shifts underpinning rates
Rates vary with construction wages, permit costs, contractor availability, disposal fees, and local soil conditions. In lower-cost markets with straightforward access, quotes may be 10%-20% below the national planning midpoint. Major metropolitan areas and high-cost coastal markets can run 15%-35% above it, especially where labor is scarce or site access is restricted.
Use the national per-foot range as a comparison point, then adjust for local conditions rather than treating it as a guaranteed price. A $2,000-per-foot estimate may be competitive in one city and unusually low in another if it excludes design or inspections. Rural locations may have lower labor rates but higher mobilization or concrete delivery charges when specialist crews travel farther.
Soil and climate can also affect local scope. Expansive clay, high groundwater, freeze-thaw exposure, or settlement near drainage problems may lead an engineer to specify additional support or water control. Ask bidders to explain any regional surcharge and identify whether it reflects labor, travel, disposal, permit fees, or a design requirement.
Which permit and repair charges belong in the budget
Most structural underpinning requires a permit and engineering documentation, but requirements depend on the local building department and project scope. Budget around $300-$3,500 for permit and inspection fees in many residential cases, with complicated projects or repeated inspections potentially costing more. Engineering may add $1,000-$6,000 or higher for complex designs and additional site visits.
Confirm the permit, inspection, and engineer costs before comparing contractor totals. Some contractors coordinate permit applications but list municipal fees separately; others include them in a combined estimate. The owner should also verify whether inspections are required before pits are filled or concrete is placed, since missed inspection points can cause delays and corrective work.
Underpinning may be part of a larger repair where drainage, leaking pipes, or poor grading contributed to movement. Fixing the cause can add $1,000-$10,000 or more for drainage corrections, plumbing repairs, or waterproofing. These items should be priced separately so the foundation-support work is not confused with optional improvements or unrelated remodeling.
How to lower the underpinning price without cutting structural work
Keep the project scope tied to the engineer’s findings. A contractor should not add length or extra support points without a documented reason, but reducing the designed scope without approval can compromise the structure. Ask the engineer to explain the required support locations and whether a phased approach is safe and economical.
Compare itemized bids for the same design, access conditions, and restoration level. Get at least three qualified estimates where available, and check that each includes the same wall length, pit sequence, concrete specification, temporary support, hauling, permit coordination, and cleanup. Request separate prices for drainage or finish work that is not essential to stabilization.
Some practical savings come from clearing basement storage, arranging access, and removing nonstructural items before the crew arrives, if the contractor approves. Combining adjacent foundation work may reduce repeated mobilization, while scheduling outside peak demand can improve availability. Avoid choosing a bid solely because its per-metre rate is lowest; a quote that omits engineering, disposal, or inspections may cost more after change orders.
Repair options should be compared only after a structural assessment. Crack sealing or drainage work may address water entry but will not replace underpinning when the foundation lacks adequate support. Conversely, a localized problem may not require underpinning an entire wall. The least expensive sound plan is the one that corrects the verified cause and meets the engineer’s design, without unrelated upgrades.