The rebuild cost of the building has not been assessed in the last 3 years.
You told us: Rebuild cost last assessed more than 3 years ago.
Why it matters
Underinsurance triggers the average clause, which reduces a claim in proportion to the shortfall.
The rule and source
Register C03 (Insurer Condition)
Property118 - HMOs: do you need different insurance?: https://www.property118.com/hmos-do-you-need-different-insurance/Property118 - Underinsurance and the average clause: https://www.property118.com/underinsurance-and-average-clause-landlords/How to fix it
Obtain a rebuild cost assessment, including HMO upgrades, fees and debris removal.
Deadline
Before the insurance renewal on 3 January 2027
Register timing: At inception and every renewal; on any change
Indicative penalty exposure
Claim reduced (average), declined, or policy voided for breach of condition/warranty or non-disclosure.
