Architecture studio Bradley Van Der Straeten has recently extended a house in London by adding an additional half-storey hidden from the street. Called Two and a Half Storey House, the extension sits no higher than the original building’s roofline. This circumnavigates a local planning restriction that prevents the construction of a single-storey extension.
The clients owned the existing two-storey, two-bedroom property, located on a central London Housing Estate. With a second baby on the way, they needed more space. Priced out of three-bedroom properties in the area they decided to investigate what could be done to create more space in their existing home.
The challenge with this property, unlike others on the estate, they were unable to secure planning permission for a single-storey loft extension. They received two planning refusals since they were not permitted to build any higher than the highest point of the existing roof, due to its lower profile.
“We approached the design as an interlocking jigsaw,” said Bradley Van Der Straeten. “We knew the half-height of the loft was fixed so the design was all about creating two interlocking floor levels in the space of one and a half floors. Integrating the bed frame into the fabric of the design allowed space to be freed up for other things such as the communal circulation spaces.”
The whole design of the project hinged on using the ceiling of the bedroom below as a bed platform for the bedroom above, which is spacious and light due to the effective use of roof windows. Integrating the bedframe into the fabric of the design allowed space to be freed up for other things such as the communal circulation spaces. Plywood unifies all the new and old spaces and helps to conceal lots of clever storage spaces.
Close attention to millimeter detail ensured ceiling heights could be maximized, which included exposing structural timbers in the ceilings and using vacuum insulation panels to limit floor and roof depths.
“The clients are delighted with their new house and love being able to see their eldest son playing in his new loft bedroom from the hallway window on the first floor, thanks to the split levels,” continues the studio.
The exterior of the extension is subtly clad in black tiles that help it blend in with the roofs of the surrounding homes.