Groundworks Cost Calculator
Estimate groundworks costs for your scheme, compare typical package budgets and request a priced quote when you are ready.
Groundworks budget calculator
Model indicative low, likely and high budgets from project inputs — for early feasibility only.
Roads & sewers required
Piling required
Select project details and calculate to see low, likely and high indicative budgets.
Indicative figures only. Final costs depend on specification, ground conditions, authority requirements, access and programme. Obtain priced quotations before committing budget.
Typical project costs
Indicative UK budget bands by package — use the calculator above for your scheme, then request a site-specific quote.
House foundations
£12,000 – £45,000
Strip, trench fill and shallow foundations for single dwellings and extensions.
View serviceRaft foundations
£25,000 – £90,000
Raft slabs and ground beams where ground conditions or layout need a spread foundation.
View serviceRoads & sewers
£50,000 – £1,000,000+
Estate roads, adoptable drainage, bonds and S38/S104 programme allowances.
View serviceSite preparation
£2,000 – £25,000+
Clearance, strip, fencing and enabling works before main civils mobilise.
View serviceAttenuation systems
£15,000 – £150,000+
SuDS storage, chambers, flow controls and adoption-related civils interfaces.
View serviceCommercial groundworks
£200,000 – £600,000+
Enabling works, foundations, drainage and access for commercial and industrial units.
View service
What affects groundworks costs?
These factors most often move groundworks budgets between feasibility and tender — price them early, not at mobilisation.
Ground conditions
Very HighSoft ground, rock, groundwater and contamination reshape dig, piling and treatment cost.
Access restrictions
HighRestricted plant, haul routes and traffic management reduce productivity and add prelims.
Utilities
HighUndertaker diversions, trial holes and highway interfaces often sit on the critical path.
Excavation depth
HighBasement boxes, reduced dig volumes and cart-away rates move earthworks budgets quickly.
Drainage requirements
HighAdoptable sewers, pumping and SuDS storage add civils scope and inspection cycles.
Programme constraints
MediumPhasing, sectional completion and winter working influence method, prelims and risk.
Real-world example project budgets
Reference scenarios for commercial conversations — adjust for ground, adoption, utilities and programme on your site.
Small extension
- Project type
- Domestic extension / alteration
- Typical groundworks budget
- £8,000 – £35,000
- Key cost drivers
- Access, foundation type, drainage connections, party-wall constraints.
Self build house
- Project type
- Single dwelling new build
- Typical groundworks budget
- £40,000 – £120,000
- Key cost drivers
- Ground conditions, piling risk, services connections, muck away.
10 plot development
- Project type
- Small housing scheme
- Typical groundworks budget
- £150,000 – £350,000
- Key cost drivers
- Estate infrastructure, attenuation, utility lead-ins, phased delivery.
50 plot development
- Project type
- Medium housing development
- Typical groundworks budget
- £750,000 – £1,500,000+
- Key cost drivers
- Adoptable roads, sewers, SuDS, bonds, authority inspection cycles.
Commercial unit
- Project type
- Commercial / industrial unit
- Typical groundworks budget
- £200,000 – £600,000
- Key cost drivers
- Heavy-duty paving, drainage, utility diversions, restricted access.
Roads & sewers package
- Project type
- Standalone infrastructure civils
- Typical groundworks budget
- £400,000 – £900,000
- Key cost drivers
- S38/S104 adoption, bonds, TM, inspection hold points, as-built records.
Ready for a priced groundworks quote?
Share your layout, programme and scope — we will respond with practical next steps for budgeting and delivery.
Need trade-specific cost guidance?
Explore foundation, piling, drainage and excavation cost guides by trade — useful for unit rates and budgeting context alongside your calculator estimate.
Development cost comparison
Quick comparison for feasibility meetings — not a substitute for priced quotations.
| Project type | Typical budget | Complexity | Programme risk |
|---|---|---|---|
| Extension / self build | £12,000 – £90,000 | Low – medium | Low |
| Small housing development | £165,000 – £500,000 | Medium | Medium |
| Large housing development | £720,000 – £1,500,000+ | High | High |
| Commercial development | £310,000 – £1,000,000+ | Medium – high | Medium – high |
| Infrastructure package | £620,000 – £2,000,000+ | Very high | Very high |
Package cost breakdown
Ranges shown for guidance only. Obtain priced quotations for your site and specification.
Site clearance
£2,000 – £25,000+
Vegetation, strip, fencing and enabling works before main civils.
Excavation
£5,000 – £100,000+
Bulk cut/fill, basement boxes, reduced dig and cart away.
Foundations
£10,000 – £500,000+
Strip, trench fill, rafts, ground beams and associated concrete works.
Drainage
£5,000 – £250,000+
Foul and surface water, attenuation and adoptable sewer packages.
Roads & sewers
£50,000 – £1,000,000+
Estate roads, adoptable drainage and highway tie-ins.
Piling
£10,000 – £500,000+
Mini, CFA and other piled solutions with testing and caps.
Related commercial guides
- Groundworks Cost Guides by TradeFoundation, piling, drainage and excavation cost explainers — educational guides hub.Read guide
- Ground Conditions ExplainedGI scope, unforeseen ground risk and commercial contingency.Read guide
- Utility Diversions for Development SitesUndertaker lead times, trial holes and diversion budgeting.Read guide
- Roads & Sewers Contractors GuideProcuring adoptable roads, sewers and programme control.Read guide
- Drainage Adoption ProcessS104 adoption, inspections, vesting and bonds.Read guide
- Infrastructure Bonds & SuretiesS278, S38 and S104 security and cash flow.Read guide
- Groundworks Tendering GuideTender packs, bid comparison and award discipline.Read guide
- NEC vs JCT for Groundworks ProjectsRisk allocation, variations and payment administration.Read guide
Before requesting groundworks prices
Tick off readiness items before issuing tender packs or requesting formal quotations.
0 of 8 readiness items checked
Frequently asked questions
How much do groundworks cost?
Domestic extensions often sit in lower five-figure bands; housing and commercial infrastructure can run from low six figures to seven figures plus. Use the calculator above for indicative ranges, then obtain site-specific quotes.
What affects groundworks pricing?
Ground conditions, access, specification, drainage and adoption requirements, utilities, programme, and whether piling or structural concrete is included. See the cost drivers section on this page.
Do I need a site investigation first?
For most structural groundworks and piling, yes. Ground investigation reduces guesswork on bearing capacity, groundwater and contamination — and improves tender accuracy.
How much does piling cost?
Piling is sensitive to depth, diameter, ground type, testing and caps. Indicative project allowances often increase total groundworks budget materially compared with shallow foundations.
How much does drainage cost?
Private drainage may be modest on small schemes; adoptable sewers, attenuation and pumping can reach six figures on larger developments. See utility diversions where services affect routes.
How much do roads and sewers cost?
Estate roads and adoptable drainage commonly sit in high five-figure to seven-figure territory depending on length, specification and adoption programme. See S38 and S104 programme for sequencing context.
Are utility diversions expensive?
They can be, especially on constrained sites and live highways. Undertaker programmes and traffic management often sit on the critical path — budget early, not at mobilisation.
What causes groundworks budgets to increase?
Unforeseen ground, design change, utility clashes, adoption rework, winter methods, and scope added after tender without repricing.
Can I get an estimate before planning approval?
Indicative budgets yes — priced quotations need enough layout, levels and ground information to define scope. Planning approval alone does not replace technical scope for civils pricing.
How accurate are online cost calculators?
They are useful for early feasibility bands only. This calculator uses simple rules; final costs depend on specification, ground conditions, access and programme. Always follow with formal quotes.