Interior view of a modern office with a black leather chair, tall bookshelf, and a sculpture bust, seen through glass with a garden outside, architecture by Gresford Architects.

A modern building with a staircase, partly obscured by lush greenery, framed by a wooden balcony railing; architecture by Gresford Architects.

Modern multi-level courtyard with timber fences and garden, featuring balconies and staircases, designed by Gresford Architects.

Bright home office with large window, white walls, wooden floor, bookshelves, armchair, and unique ceiling design, architecture by Gresford Architects.

View of a rooftop terrace with plants, glass doors, and neighbouring buildings under a partly cloudy sky, architecture by Gresford Architects.

Interior staircase with natural light, white walls, and wooden railings, featuring a hanging light bulb, architecture by Gresford Architects.

Modern interior office with large windows, white walls, wooden floor, and minimalist furniture, with outdoor balcony; architecture by Gresford Architects.

Modern wooden slatted building with a tree and blue sky in the background, architecture by Gresford Architects.

Open courtyard with colourful doors, wooden fencing and a rooftop terrace with plants and umbrellas, architecture by Gresford Architects.

Four roof extensions to adjoining modern mews houses in North London.

Gillett Place is a development of 9 flats and 4 mews houses completed in 2007 by Hawkins Brown. The mews houses — the subject of the work — had three external spaces — a first floor balcony and two second floor roof terraces. The two roof terraces were divided laterally by a structure which houses the stair to the roof.

The rear terraces, which are to the north of the houses, were underused by all residents who decided to submit a joint planning application to construct a room on each of the rear roof terraces.

Each of the new rooms has new glazed wall with glazed doors to the south elevation which allows light to flood into the centre of the house plan, where it didn't before.

A mansard roof to the north elevation stops any loss of light to the houses behind and provides space for a row of extra storage units within the eaves. Each room will be used in a different manner by the residents, and the design of each room is individual including, to an extent, the facade treatment.