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Landlord Insurance Reinstatement Cost UK

Reinstatement cost vs market value: why they differ and why insuring for market value causes underinsurance. The averaging clause, BCIS House Rebuilding Cost Index, RICS Reinstatement Cost Assessment, Day One Reinstatement basis, index-linking, and non-standard construction considerations.

10 min readUpdated 7 June 2026Last reviewed: 17 May 2026insurancebuildings-insurancereinstatement-costunderinsurance

Reinstatement Cost vs Market Value

The reinstatement cost comprises demolition and site clearance + professional fees (10–15% of build cost) + rebuild to current Building Regulations standard + VAT. Market value includes the land (which cannot be destroyed) and fluctuates with supply and demand. In high-land-value areas, market value can be double the reinstatement cost. In some areas, reinstatement cost exceeds market value — particularly for listed or non-standard buildings.

Under-Insurance and the Averaging Clause

Most landlord buildings policies contain an averaging clause. If the sum insured at the time of a loss is less than the actual reinstatement cost, the insurer pays only the same proportion of the claim: (sum insured ÷ actual reinstatement cost) × claim amount. Example: sum insured £300k on £400k rebuild (75%) — a £100k claim pays only £75k. Applies to partial losses, not just total loss.

BCIS House Rebuilding Cost Index

The BCIS (Building Cost Information Service) free online rebuild cost calculator gives a rebuild estimate for standard residential properties. Updated annually; check at each renewal. Limitations: calibrated for standard construction; understates cost for listed buildings, large properties, or non-standard construction.

RICS Reinstatement Cost Assessment

For listed, non-standard, or complex properties, a formal RICS Reinstatement Cost Assessment (RCA) is recommended. Cost: £300–£600 standard residential; £800–£2,000+ for listed or complex properties. RICS recommends updating every 3 years; reviewing against BCIS annually.

Day One Reinstatement and Index-Linking

Day One Reinstatement: insurer agrees to pay actual rebuild cost at the date of loss, up to an agreed percentage uplift (typically 50%) above the declared sum — removes averaging risk for the policy year. Index-linking automatically adjusts the sum insured annually in line with the BCIS index.

Frequently asked questions

Should I insure for market value or rebuild cost?+

Always the rebuild (reinstatement) cost. Market value includes land (which cannot be destroyed) and fluctuates with market conditions. Insuring for market value almost always results in underinsurance and the insurer applying the averaging clause at claim time.

What is the averaging clause?+

If your sum insured is less than the actual reinstatement cost at the time of loss, the insurer pays only the proportional share of the claim. Insured for 75% of rebuild cost = insurer pays only 75% of any claim, even a partial one.

What is Day One Reinstatement?+

A policy basis where the insurer agrees to pay the actual rebuild cost at the date of loss up to an agreed uplift above your declared sum (typically 50%). Removes the averaging risk for the policy year regardless of construction cost inflation.

Found a gap or disagree with something?

Reply to any LetSafe email or write to Richard@letsafeuk.co.uk. We rewrite guides when we get something wrong, the sooner we hear, the sooner we fix it.

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