Missing paperwork does not prove that work was never approved, but it also does not establish compliance. Investigate the evidence and actual condition before making a claim to a tenant, buyer or insurer.
Establish the history
- Identify when the work occurred, who did it and what approvals are found.
- Compare the current layout with records and any approved plans.
- Keep planning, building approval and licensing questions separate.
Assess the actual work
- Use competent professionals to identify urgent risks and concealed details needing investigation.
- Ask the local authority or verifier which route is available for the age and type of work.
- Do not continue unsafe occupation while treating the matter only as a paperwork exercise.
Complete the correction
- Agree a scope, programme and necessary inspections.
- Retain evidence of remedial work and the final authority outcome.
- Update property descriptions and disclosures accurately, distinguishing verified facts from unresolved matters.
Build a factual history before approaching the authority
The route depends on what was done, when it was done and the relevant country's system.
- Collect dated plans, photographs, invoices and previous owner information. Separate evidence of the work's date from estimates or assumptions.
- Ask the relevant building authority what evidence and opening-up it needs. Planning regularisation and building-control acceptance answer different questions; neither should be presumed from a council-tax entry.
- Assess present safety and any immediate restrictions on use while the approval position is resolved. Preserve the authority's written decision and limitations, rather than describing a pending application as retrospective approval.
Example: records show a different flat layout
A fictional council file contains an approved conversion, but an extra bedroom has since been created. Investigate the later alteration separately. Finding one historic approval does not validate every feature of the current layout.
What to do
- Search the authority, owner and professional records.
- Have the actual work and safety assessed.
- Agree the appropriate country-specific route and complete required work.
Evidence to keep
- Record searches, drawings, dates and inspection findings.
- Authority advice, applications, remedial work and final documentation.
Sources and guidance
- Building regulations approvalUK Government · checked 20 October 2026
- Converting a house into flats or bedsitsWelsh Government · checked 20 October 2026
- Getting a building warrantScottish Government · checked 20 October 2026
Related guides
- Check asbestos before disturbing building materials
- Check Welsh building approval before conversions
- Separate Welsh fire design from building safety duties
- Get the right building control approval in England
- Identify the higher-risk building route in England
- Check the Scottish warrant and completion process