A 16th-Century Kent Barn Gets a Corten Steel Roof — on a Heritage Officer's Suggestion

A Grade 2 listed 16th-century barn in Kent now wears a laser-cut Corten steel roof — and the idea came from the local heritage officer, not the architects. 'It was actually the heritage officer who suggested a Corten steel roof to provide a clear distinction and contemporary twist on the clay tiles,' says Sandy Rendel, principal of Sandy Rendel Architects, the South London practice behind the project.

The oak-framed barn, which sits in the High Weald Area of Outstanding Natural Beauty, was converted into a dwelling in 2003. That earlier work left the building divorced from its context. It closed off the connection from the original farmhouse and entrance yard, and the resulting orientation disconnected the house from the section of garden allocated to the new dwelling.

The owners, a curator and a joinery designer, wanted to update and enhance the layout. They commissioned Sandy Rendel Architects — best known for Bury Gate Farm, an award-winning house on the South Downs, and an elegant village residence — to improve the outlook. 'Extensive negotiations' with the planners produced a breakthrough for the design of a new kitchen extension that transforms the interior arrangement of the former barn.

What does the extension actually change?

'The main aim of the project was to help reorientate the house and offer a much clearer connection with the external spaces and views across the fields to the southwest,' says Rendel. The new kitchen extension opens the barn toward its garden, reversing the dead-end orientation left by the 2003 conversion.

The Corten roof is the project's signature move. 'We ran with the idea and developed the concept of expressing the roof very directly and abstractly as these simple sheets of metal with fine crisp edge that stands out against the wavy softness of the sagging original roof and its original handmade tiles,' Rendel explains. Laser-cut slots running around the perimeter of the steel feed a recessed gutter tucked beneath the eaves. Dark zinc downpipes blend with the black stained larch cladding on the extension.

The new addition is a timber-framed structure, matching the construction method of the original barn. The carpentry of Scott Partnership, which built the framework, is fully revealed — roof rafters, ridge, hips and collar ties all exposed. Large sliding glass doors open onto the garden, their span carried by a single slender square column, rotated 45 degrees to the other timbers, supporting the ring beam.

A glazed structural link keeps old and new spiritually connected but visually distinct. Inside, the kitchen cabinets — built by the client, a joinery designer — follow the grain and texture of the roof structure above.

Rendel frames the project as a study in finesse rather than scale. 'The project is one of the smallest things we have done but it was great to really get into the fine details of the timber connections,' he says, calling it 'a truly collaborative process with engineers Foster Structures and St Pierre Contractors, along with the frame makers and the clients themselves.'

The barn shows what patient negotiation with UK heritage legislation can yield: a listed structure that gains a contemporary layer without erasing its sagging, handmade-tiled character.