Rebuild cost calculator UK
Research your house rebuilding costs using its floor area, property type and UK region. This free calculator applies editable build-rate assumptions and allowances for fees and clearance. Use the result as a starting point for a buildings insurance discussion, not a confirmed sum insured or the property's market value.
Measure inside the external walls, across every storey. 1 m² = 10.76 ft².
Enter your own rate if you have one — it replaces the default. The regional factor and other allowances still apply; check that you are not counting these costs twice.
£316,109
Working range £284,498 – £347,720
- Construction
- £282,240
- Fees, clearance & debris removal (12%)
- £33,869
This is an indicative estimate for standard construction, produced from the fixed assumptions shown below and a regional factor. The defaults are not live quotations or a BCIS valuation. It is not a substitute for a RICS or BCIS assessment. Listed buildings, non-standard construction, unusual sites, and larger commercial risks should be professionally assessed before you set a sum insured.
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Use the gross internal floor area across all storeys, rather than the plot size. Select the house type and region, then include a garage or basement if applicable. The calculator also has options for flats and commercial buildings; those estimates carry the same limitations.
If you already have a BCIS or surveyor build rate, use the optional rate override. The editable defaults below are indicative assumptions, not a property-specific survey or live BCIS valuation. Check the result with your broker or insurer before relying on it for insurance; listed buildings and non-standard properties need a professional assessment even when an uplift is selected.
Rebuild cost is not market value
Market value is the price a property could sell for, including its land and location. Rebuild cost concerns reinstating the building, including relevant fees and clearance costs, rather than buying the land again. A sale price does not tell you the rebuilding cost, so do not use it as an automatic substitute for a buildings insurance valuation.
How rebuilding costs relate to buildings insurance
A buildings sum insured needs to be considered alongside the policy's basis of cover. If an average clause applies, a shortfall in the insured value may reduce a claim payment. Conditions and exceptions vary, and this calculator does not read your policy or establish whether you have adequate cover. Discuss the figure and policy terms with your broker or insurer before setting or changing cover.
Rebuilding-cost assumptions and exclusions
- Construction cost based on floor area, property type and a regional cost factor.
- A fixed £22,000 garage or outbuilding allowance when selected, and a basement allowance of 18% of construction cost when selected.
- A 35% heritage uplift on construction plus extras when selected; this does not assess a listed building's specific requirements.
- 12% for professional fees, site clearance and debris removal.
It does not include contents, stock, machinery, loss of rent, alternative accommodation, or the cost of complying with local authority requirements on a rebuild. Consider these separately with your broker or assessor. The calculator does not inspect the building, price individual materials, or automatically update rates for inflation.
How the rebuild cost is calculated
Floor area (m²) × build rate for the property type × regional factor, plus any garage, basement or listed-building allowance, then 12% for professional fees, site clearance and debris removal. The working range is simply 10% below and above the estimate, not a surveyed range or a guarantee of actual costs. Example: a 120 m² detached house in the South East at £2,100/m² gives £316,109 including fees.
| Property type | Indicative build rate (per m²) |
|---|---|
| Detached house | £2,100 |
| Semi-detached house | £1,950 |
| Terraced house | £1,850 |
| Bungalow | £2,000 |
| Flat / apartment block | £1,900 |
| Office (commercial) | £2,250 |
| Shop / retail unit | £1,750 |
| Warehouse / light industrial | £1,150 |
Regional factors range from 0.88 (Northern Ireland) to 1.25 (London). If you have a surveyor or BCIS rate, enter it in the calculator to replace the default. The regional multiplier and 12% allowance still apply; a rate that already includes them could double-count those costs.
Rebuild cost questions
What is a rebuild cost?
What it would cost to demolish, clear and rebuild the property to its current specification, including professional fees and site clearance. It is not the market value or the purchase price.
Is a rebuild cost calculator accurate enough for insurance?
It gives an indicative figure for standard construction. Listed buildings, non-standard construction, unusual sites and high-value or commercial properties should be assessed by a RICS surveyor or a BCIS-based valuation.
What happens if the sum insured is too low?
If your policy includes an average clause, underinsurance may reduce a claim payment in proportion to the shortfall. The outcome depends on the policy wording and any applicable conditions or exceptions. This calculator does not check your policy terms.
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