2.1 The roof question

In the adoption of a roofed model informed by constructional detail borrowed from other brochs, the unique design of Mousa broch appears to have been overlooked. Armit's view of broch towers as imposing status symbols, homes of a warrior elite (Armit 2003, 68–72) does not support the possibility that different brochs specialised in or fulfilled different roles in the lives of their communities. A multi-functional or specialist role for the brochs has not been investigated. In his 1890 paper, Dryden considered both sides of the debate over whether Mousa broch had a roof or floors within it.

The roofs are…supposed to have been conical, with an aperture for smoke in the centre, and with the eave of the roof on the outer edge of the tower. On the other side, it is argued that no signs of insertion of beams or rafters exist in any one. If the builders had timber and skill to floor and roof them, why did they spend so much labour in making thick walls and chambers in them?
(Dryden 1890, 201)

Dryden argues that a roof on top or floors within the broch would prevent light from entering the voids and the courtyard and concludes from the architectural evidence that the Mousa broch was unlikely to have a roof. In contrast, in his book Towers in the North, Ian Armit reasons that there must have been a roof on the brochs to protect the inhabitants from the effects of the Atlantic Scottish winter (Armit 2003, 68–72). He continues 'Given that their ancestors had been building warm secure and fully roofed roundhouses in timber and stone for many centuries it is hard to believe that the broch builders would have exposed themselves to these problems' (ibid.). A cross-sectional illustration of the interior of Armit's version of Mousa broch shows multiple floors and living spaces dividing the height of the broch; this theoretical reconstruction is inferred from observations of other brochs and broch-like structures. The illustration of Mousa broch currently displayed to tourists on the site, showing a thatched conical roof on top of the wall head, is a reproduction of this model.

There is a world of difference between a roofed structure built with the comfort of its inhabitants in mind and Dryden's unroofed broch in which the sun illuminates the voids and the courtyard is exposed to the sky. A review of the archaeological evidence can help us better understand these apparent contradictions. Post-holes have been discovered at Dun Troddan, Glenelg, but have not been found in the courtyard of Mousa. Historic Scotland confirm that despite repeated investigations of all areas at the wall head of Mousa broch, no evidence of supporting roof structures is apparent (Scott Hamilton, pers. comm.; Noel Fojut, pers. comm.). The suggestion that the stone scarcements within the inner walls of the broch were built to support internal roofs is convincing; however, no roof materials are reported among the remains excavated from the courtyard. Most significant is the layout of the broch; Mousa's design and construction does not suggest a roofed domicile. Because of the thickness of its walls at ground level, the available space within is limited. Moreover this available space is difficult to access. Around the courtyard, the only accessible spaces (cells A, B and C) are not luxurious living areas but large beehive-shaped cells. Above the stone scarcement (12.5 feet: 3.8m), the space contained in galleries 1–6 is narrow and difficult to access (Figure 3). Because of its design, any living space within the broch becomes limited to that area within the courtyard and its inner walls; only when supplied with ladders and floors does this area become available for domestic occupation. The unexplained anomalies of design and construction (voidsets/niches, gallery spaces, stairs, courtyard) of Mousa broch support the proposal that the broch could have been roofless and that part or all of the courtyard has always been open to the sky.


© Internet Archaeology/Author(s)
University of York legal statements | Terms and Conditions | File last updated: Thu May 26 2011