Adding floors above existing buildings — applied to City of Westminster in the Greater London. With intensive Gateway 3 sign-off and HRB oversight and an average build cost of £3400/sqm, the deal arithmetic for airspace & Rooftop Development here is distinct from neighbouring boroughs.
Heads up: City of Westminster operates Article 4 directions, so airspace & Rooftop Development that would normally be permitted development will likely require a full planning application here. Build that into your timeline and risk model.
Run any Greater London listing through Scapely to get a property-specific build cost, council objection-risk score and the Roof-Loading & PD Eligibility Check overlay applied to City of Westminster's policy environment.
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