54 Northumberland Place London W2 5AS
Excavation of a new basement level to include front lightwell, Extend existing external staircase and railings leading down to lower ground floor; Excavate rear garden down to meet proposed lower ground floor level; Form new lower ground floor extension; Adapt existing rear outrigger and increase height by one storey; Erect replacement infill rear conservatory at ground floor level with associated new terrace; Adapt existing mansard to sit in line with no.53; Replace all sash windows with new timber, double glazed windows to match existing; Replace front garden plinth, piers and railings.