THE DILEMMA: David and Melissa have just bought a Grade II listed townhouse in East London that has a one-storey L-shaped building at the rear; it was built in the 1950s as workshops and is now used as an artist’s studio. The couple relish the prospect of living in 3,229 sq ft (300 sq m) of space with their three young children, but are unsure how to create a more streamlined home and retain each property’s best features.

THE SOLUTION: David and Melissa are lucky to have found such a gem of a property. Terraced houses such as this, with additional buildings at the rear, are rare in Spitalfields.

As well as housing the studio, the L-shaped building at the rear offers invaluable, enclosed guest quarters that include a shower room, kitchenette and sitting room — which would be ideal for David and Melissa’s live-in nanny.

The master suite on the top two floors of the main house incorporates a bedroom that opens on to a terrace through full-height concertina glass doors, plus a dressing room and en suite bathroom. This is an arrangement that David and Melissa would like to retain, while also adding two or three more bedrooms. The solution lies first in connecting the two buildings, converting a thoroughfare into usable living space while reconciling the four ground levels within the short distance — 13ft (4m) — between the back door of the house and front door of the studio building. Moreover, they must also secure listed building consent and planning permission, so a really good architect is needed.

The newly realised interior space of about 215 sq ft (20 sq m) could become a new bedroom or even bathroom. As there is already an outdoor lavatory in the vicinity, locating services should not pose too much of a problem. Either way, the scheme could then be developed to relocate the kitchen/diner from the lower ground floor of the main house into the light-filled studio building, which is large enough also to accommodate a family room. The lower ground floor of the main house could then be used as bedroom or bathroom, thus adding two further bedrooms.

Putting a building over what would have been the garden means that David and Melissa no longer have a good-sized garden, which is not ideal for a young family. Hence I would create a garden on the flat roof of the studio building. Given that it is so well lit, one of the two skylights could be given up to create such a garden, accessible via a staircase through the other roof-light, which consequently would need to be redone as a small glazed roof-top extension.

Although the studio building is modest in design it features a lot of steel — four reinforced steel joists, to be precise — so no further bracing should be necessary and the landscape gardener can get to work creating a lush and well-fenced space for dining and playing. With three bedrooms in total, plus the “guest house” adjoining the tail end of the studio, David and Melissa will have deftly turned a two-bedroom house into a four-bedroom home. If they feel that they need more bedroom space, however, the existing study could be used as an additional bedroom.

Henning Stummel Architects: 020-7262 1778 ; Maya Vuksa Architecture and Design 020-8968 6250; for landscape gardeners contact Mylandscapes, 020-7485 6464, www.mylandscapes.co.uk www.timesonline.co.uk/interiors

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