House No.7

A masterly example of adaptive re-use, House No.7 taps into local history, landscape, culture and microclimate.

About this project

Tiree is the most westerly island of Scotland’s Inner Hebrides: between it and Canada there is only ocean. Tiree is edged with long, sandy beaches. The traditional dwelling form here is the Black House, a low, single-storey structure with thick, white-painted walls built from local rubble and with a steeply-pitched turf or thatch roof to shelter its residents from the harsh environment outside.

Nowadays, the island’s 7834 hectares of machair landscape is sparsely populated (the most recent census in 2011 registered 653 inhabitants) and the ruins of former dwellings stand as mute criticism of slow decline. Some of these structures are considered to be of sufficient historical merit to justify listing by Historic Environment Scotland, one such being House No.7 (2013), the black house rebuilt and extended for his parents by the principal of Denizen Works.

The rebuilt and extended project has three constituent parts: the ruined black house has been converted to a guest suite containing two bedrooms, a bathroom and a snug within the two-storeys that now sit beneath its steeply sloped and black-tarred roof; the barrel-vaulted ‘Livinghouse’ containing the dwelling’s living, dining and kitchen areas; and the utility block that houses a utility room, a wet room for coats and boots and a small studio space.

The Livinghouse and the utility block are linked to form an L-shape that wraps around one end of the rebuilt black house and provide shelter to a small garden that has been created to the rear. A top-lit passageway connects the three quite different built elements, the design and construction of which have, on the one hand, been grounded in careful analysis of the vernacular buildings of Scotland’s Highlands and Islands and, on the other, the practicalities of construction in remoter areas.

In the case of treeless Tiree, the prospect of gales is a fundamental consideration, with House No.7’s timber frames having to be engineered to withstand a horizontal wind loading of 1.44 KN per sq/m. Supply of building materials and components was also constrained by what could be shipped to the island aboard a CalMac ferry and, with the structures of both the Livinghouse and the utility block formed from curved glulam portal frames CNC machinetailored for the project, the design had to accommodate these being fabricated and assembled in easily transported sections.

The roofs to the Livinghouse and the utility block are clad with sinusoidal galvanised steel sheets—‘wrinkly tin’, in the local vernacular—with the gable ends to the Livinghouse clad with wide (150 x 22mm), tar-painted Scottish larch planks, installed vertically and fixed board-onboard. The stone walls of the black house guest suite have been lined with an insulated timber frame, whilst the roof above was constructed using traditional timber frame methods and topped with a curved ridge formed from profiled timbers. Pine tongue-and-groove boards—a traditional material in this part of the world—are evident throughout the interiors, the pièce de résistance being the church-like barrel-vaulted ceiling to the living/dining/kitchen area of the Living House.