Estimate Your House Build Costs

Enter your floor area, specification and location. Every assumption is shown and editable, and construction is separated from fees, surveys, infrastructure, VAT and contingency.

Build cost calculator

Illustrative placeholder benchmarks configured by Carters — replace with approved, sourced rates before relying on them. Date: 2026-06-01. Scope: UK, new-build dwellings, indicative only. Override the rate if you have a current quotation or cost plan.

Gross internal floor area (sqm)Project typeSpecificationLocationOverride base rate (£/sqm, optional)External works (% of construction)Professional fees (%)Surveys allowance (£)Infrastructure & connections (£)Contingency (%)VAT rate (%)Finance costs (£)

VAT: new-build dwellings are often zero-rated; conversions may qualify for a reduced rate; extensions are usually standard-rated. Confirm with HMRC guidance or your adviser.

Construction 180 sqm × £2,200/sqm	£396,000
External works 10% of construction	£39,600
Professional fees 12% of construction + external	£52,272
Surveys Fixed allowance	£6,000
Infrastructure & connections Fixed allowance	£15,000
Contingency 10% of subtotal	£50,887
VAT 0% of construction + external	£0
Finance Fixed allowance	£0

Indicative total

£559,759

£3,110/sqm overall

Excludes: Land purchase, legal and agent costs; Loose furniture and landscaping beyond the external works allowance; Abnormal costs not entered above; Future inflation. Indicative estimate only — not a contractor quotation.

How the estimate is built

Construction = floor area × base rate × regional factor × project type factor. External works, fees and contingency are percentages; surveys and infrastructure are fixed allowances you can edit. VAT is applied to construction and external works at the rate you select.

Exclusions

Land purchase and legal costs
Furniture, fittings and landscaping beyond the allowance
Abnormal ground conditions unless entered
Inflation beyond today's assumptions

Important

Outputs are indicative estimates, not contractor quotations. Benchmark rates shown are configurable by Carters and display their source, date and scope.

This page provides general, preliminary information. It is not a planning decision, formal valuation or professional appointment. Appropriate checks and current planning information may be required. Last reviewed 2026-06-01.