VCONST24300 - DIY builders and converters VAT Refund Scheme - eligibility of claims: condition 4: were the works carried out lawfully?
Planning legislation requires the construction of most new buildings and conversions to be approved by a planning authority before they are carried out.
Similarly, Building Regulations require notification to be given at the start and completion of the works, and of certain intermediate stages (such as foundations and damp proof course), to allow for inspections to be carried out.
Failure to meet Planning or Building Regulations makes a claim liable to rejection on the grounds that the works weren’t lawful. Should approval for the construction or conversion be granted part way through the works being carried out, it is only those works carried out after the granting of approval that are lawful.