More room on top

Simon Conder is taken aback, slightly. In the few months since he last saw the new two-storey rooftop ‘Black House’ he designed in London Fields, Hackney, its surroundings have transformed utterly. As completed, it was an elevated eyrie with clear views on three sides. Now, it is being hemmed in by big new blocks, replacing most of the low-rise workshops next to the railway line here. Luckily our photos were taken before this part of the East London building-boom onslaught. Equally luckily, Conder’s contribution remains different enough to stand out easily from the herd.

‘I think of it as a garden shed,’ he says of the building, made of a laminated larch portal frame infilled with structural insulated panels (SIP) and clad in black-stained southern redwood lapped planks. It happened this way because his client owns the building below, which houses her design agency. Although a typically stout, thick-walled late Victorian industrial building, it has very little by way of foundations so whatever went on top had to be lightweight. Conder considered a polycarbonate box before, working with engineer Fluid, he came up with the timber-frame-and infill panel solution. It sits on a new hybrid concrete/steel ring beam holding together the top of the existing walls and concealed by recycled stock brick.

Prefabrication helped considerably, given the problems of access to the site. The sections of the envelope were made in Barnsley, trucked down and erected by crane over a fortnight, after which construction continued inside. The black timber cladding is a reference to various buildings round about which use this material – though it also reminds me of the tall fishermen’s huts on the shingle at Hastings, particularly on its south elevation where a lift shaft (same cladding, but structurally cross-laminated timber or CLT) drops to ground level. If this is a shed, though, it is a noble one with its high-level loggia, proportioned just so. 

The spaces inside are straightforward enough: two bedrooms, study, utility room and gym on the lower floor, living, kitchen/dining and an open terrace in that loggia on the upper. The staircase from the building below is extended on upward into the apartment, daylit from a simple skylight. 

Conder is famous for his one-off houses – they all appear in a new book of his, ‘Small Works’. This is the first to be perched on top of another building and it is very much a thing in itself rather than an extension. You can imagine it re-erected on a lower plinth elsewhere. It would work.