Insurance During a London Renovation: What Cover You Need and Common Gaps

The Standard Policy Gap

Most standard buildings insurance policies contain exclusions or limitations that are triggered by major renovation works:

Unoccupancy clauses: Standard policies typically exclude or significantly reduce cover if the property is unoccupied for more than 30 or 60 consecutive days. Major renovations frequently require the property to be vacated for 6–24 months. If the property is unoccupied and the insurer has not been notified, the policy may be void — not merely limited — from the point of unoccupancy.

Works exclusions: Many standard policies exclude damage that occurs as a result of, or in connection with, building or renovation works. This means that if a fire is started by a contractor's hot works, or if a water leak occurs during plumbing installation, the standard policy may not respond.

Structural change exclusions: Policies may exclude cover for structural alterations that have not been notified to the insurer. A basement extension, a loft conversion, or a significant structural reconfiguration can change the rebuilding cost and the risk profile of the property in ways that affect the insurer's exposure.

Increased rebuilding cost: If the renovation increases the floor area or the specification of the property, the rebuilding cost (the sum insured for buildings insurance purposes) will increase. Failure to update the sum insured during the renovation means the property may be underinsured at the point that cover is most needed.

The practical implication: before any significant renovation begins, the client must contact their existing insurer, disclose the nature and scope of the planned works, and establish whether the existing policy will remain in force during the works. In most cases for major renovations, the answer will be that specialist contract works insurance is required.

Contract Works Insurance (Joint Names Policy)

Contract works insurance (also known as contractors all risks insurance, or CAR) covers the works in progress — the building under construction or renovation — against damage from all causes including fire, flood, theft, vandalism, and accidental damage. It is typically arranged in the names of both the client and the contractor (a joint names policy), ensuring both parties are covered and preventing the insurer from seeking recovery from one party against the other (subrogation).

For a major London renovation, the contract works policy should cover:

The existing structure: The existing building, not just the new works. This is critical — damage to the existing fabric (fire spreading from the building site to the existing structure, water damage from burst pipes during the works) is a significant risk and must be covered.

The contract works: Materials stored on site, work in progress, and the completed portions of the new works, up to the contract sum.

Professional fees: The cost of rebuilding surveys, architectural fees, and other professional costs that would be incurred in reinstatement following a loss.

Debris removal: The cost of removing debris following a loss.

Public liability: Liability to third parties (neighbours, members of the public) for injury or damage caused by the works. Note: the contractor's own public liability insurance covers their activities; the client's policy covers their own liability as the party controlling the site.

The contract works policy should be in place from the start of works on site and should remain in place until the date of practical completion. After practical completion, the standard buildings insurance policy should be reinstated (or a new policy arranged) to cover the completed building.

Employer's Liability and Contractor's Insurance

The client commissioning a renovation has limited direct employer's liability exposure if they are engaging a contractor (rather than directly employing labour), but they should verify that the contractor carries adequate insurance:

Public liability: Minimum £5m for a residential project; £10m or £20m for larger projects or projects involving risks to the public (work in a busy London street, scaffolding over a pavement).

Employer's liability: Minimum £5m (statutory requirement for UK employers).

Professional indemnity: For design-and-build contracts where the contractor also provides design services, professional indemnity insurance covering design errors.

Contract works insurance: The contractor may carry their own contract works insurance covering their liability for the works; this does not replace the client's own contract works insurance, which covers the client's interest in the building.

Verify contractor insurance by requesting certificates of insurance at the start of the project and checking that the policy limits, the policy period, and the named insured are all appropriate. Do not accept verbal assurances — request the actual certificate.

Listed Building and Heritage Property Considerations

For listed buildings, the rebuilding cost — the cost of reinstating the property following a total loss, using materials and craftspeople of the quality required to meet listed building consent requirements — is significantly higher than the comparable rebuild cost for an unlisted property. Original lime plasterwork, period joinery, traditional roofing materials, and heritage masonry all attract significant premium costs compared with modern equivalents.

Standard buildings insurance valuation (using a cost per square metre rebuild rate) will almost always underinsure a listed building. A specialist heritage property rebuilding cost assessment — carried out by a building surveyor experienced in listed buildings — should be the basis for the sum insured in any heritage property insurance policy.

Specialist heritage property insurers (Ecclesiastical, Hiscox, Lloyds of London syndicates) have underwriting experience and claims handling expertise appropriate for listed buildings that standard home insurers may lack. For a prime listed London townhouse, specialist insurance from an insurer with heritage property expertise is the appropriate approach.

Valuables and Contents During Renovation

During a renovation, high-value contents — art, antiques, jewellery, furniture — may be stored on the premises, in temporary storage elsewhere, or in transit. The standard contents insurance policy covers contents at the insured address; items in storage or in transit may require specific endorsement or a separate fine art and valuables policy.

If the property is unoccupied during the renovation, contents left in the property may have reduced or no cover under a standard contents policy. Confirm with the insurer the extent of contents cover during unoccupancy and arrange storage insurance or a specific site security risk policy if high-value items are to remain on site.

Post-Completion Insurance Review

At practical completion, the insurance position should be reviewed comprehensively:

• —Rebuild cost: reassessed to reflect the completed renovation (increased floor area, improved specification, any additions such as a basement extension)
• —Contents: reviewed to reflect any new furniture, art, or other valuable items acquired for the renovation
• —Standard buildings policy: reinstated with the correct sum insured and the insurer informed of the works that have been completed
• —Any specialist guarantees (flat roof, waterproofing, damp-proofing, structural) noted for the policy file — these affect the claim position in the event of a related loss

A post-renovation insurance review with a specialist broker experienced in prime residential properties is a modest but worthwhile investment in financial protection for the completed asset.