Mayfair Townhouse Owner Ordered to Destroy Illegal Basement, Restore Historic Features

The owner of a Grade II-listed 18th century townhouse in Mayfair, London, has been ordered by Westminster City Council and the Planning Inspectorate to demolish an unauthorized 860 sq ft basement featuring a gym, sauna, and cinema, and to restore the building's historic features. Despite being denied listed building consent in 2010 due to potential harm to the property's architectural and historic interest, the owner proceeded with extensive alterations including enlarging the basement and removing original features such as panelling and fireplaces. The council discovered these breaches in 2020 and issued an enforcement notice in 2023, which was subsequently upheld on appeal. The restoration involves filling the illegal basement with concrete, rerouting electrics and plumbing, and reinstating original fixtures, with costs expected to run into hundreds of thousands of pounds. Geoff Barraclough, Westminster City Council's Cabinet Member for Planning and Economic Development, emphasized the importance of accountability and safeguarding Westminster's architectural heritage. The owner was described as showing a complete disregard for both the council's decision and the historic significance of the property.