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A derelict office building in Mayfair is up for sale with potential to be transformed into one of the capital's most extravagant mega mansions.
Office-to-resi conversions are more often associated with substandard housing snuck through under permitted development rights, but this Grade II-listed property is on the market with planning permission for conversion into a luxury 10-bedroom home with basement swimming pool.
The building close to Hyde Park Corner will cost the visionary buyer £35 million — before they have even begun any renovations.
Last used as office space, the 18th century building has been stripped back and left vacant and requires a significant amount of work.
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Holes can be seen in flooring, while walls and external spaces appear in need of major restoration and redecoration.
However, the scale of this job will ramp up several notches if the buyer carries out a planning consent granted in 2015.
Under this approved scheme, which is still valid for completion, the building’s basement would be deepened to fit in a pool, gym, sauna and Jacuzzi.
This lower-ground floor would also include staff quarters featuring two bedrooms, two bathrooms, a kitchen, utility room and chauffer’s office, according to plans submitted to Westminster City Council.
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The first floor would contain a 54 metre squared living room and a separate 47 metre squared family room along with a library and media space. A study, kitchen and dining room are planned for the second floor.
Spread over the three floors above are eight bedrooms and the same number of bathrooms, with the main bedroom opening on to double dressing rooms that flow onto an en suite with twin toilets.
The scheme also includes creation of a roof terrace.
Adam Byng of Hertfordshire-based quantity surveying firm PCP Surveyors estimated costs of up to £7 million to execute the planning permission to a standard expected for this type of property. Consultant fees could be added on top, he said.
Anthony Kazan, head of development at Knight Frank, said the agency expected interest from a range of parties.
“It would suit an owner-occupier whether they want it as a house or an office,” he said.
“Given the size of the planning permission it would become a large house at the top end of the central London market.”
Although conversion of office space into residential premises is allowed without planning consent using amendments to the permitted development regime, Westminster City Council has used Article 4 directions to overrule these rights across vast swathes of the borough. In addition listed building consent is required for those buildings — such as this Mayfair office — that have such heritage protection.