Feilden+Mawson were lead architects and interior designers for the successful refurbishment of six Grade II listed Georgian townhouses for The Portman Estate in Marylebone. Nos 23, 33, 51, 53, 55, and 87 Gloucester Place saw the completion of all building works in October 2016 and the subsequent occupation by Z Hotels as the operator acting on behalf of the Estate.

The works include the addition of new rear extensions, the introduction of new heating and cooling plant at roof level, new ventilation systems, full replacement of existing mechanical, electrical and plumbing services, new lifts, new basement floor slabs, upgrades to acoustics and fire resistance of walls and floors, upgrades and repair to the existing building envelopes, new roofs, as well as general changes to existing layouts on all floors throughout the properties. Bright, welcoming, multi-function breakfast rooms and outside courtyard gardens have also been designed to add to the customers enjoyment of these hidden spaces.