Grass-covered roof for Skara Brae house
Story dated: Thursday, June 7, 2007

Copyright. Reproduced courtesy of Historic Scotland

Work to install a grass-covered roof on the best-preserved Neolithic house at Skara Brae is due to be completed by the end of the month.

After extensive environmental monitoring of the conditions within the House 7, experts have conceded that the current metal and glass roof, fitted in 1930, should be replaced with a lightweight timber structure supporting a hydroponic mat roof with planted sedum grass on the top. 

It is hoped that on completion of the work, a more benign environment will be created for the interior of the prehistoric building; one which will better preserve the stone structure, fixtures and fixings.

Stephen Watt, District Architect at Historic Scotland said: ‘We are continually looking at different approaches to preserve House 7, making use of new knowledge and technology in this field.  Although the stonework may look thick and robust inside, it is actually very delicate and requires constant monitoring. 

Endeavours in the past to preserve these important remains have led to a variable environment within the building which, if left any longer, could be very harmful to the stone. 

This new state-of the-art roof will work to stabilise the climate, preventing potentially dangerous salt-laden moisture migration, and creating a safe and benign environment inside.  The sedum grass covering will allow this new structure to blend in easily with the surrounding countryside, while also providing a buffer from the extreme marine environment.”

The waterproof roof membrane under the sedum is made from polyisobutylene, an environmentally-friendly material which is recyclable. 

This will be placed over House 7 using both elements of the existing roof structure (so as not to disturb the remains within) and also a new timber structure (for areas not in contact with the historic fabric). 

Work began in mid May and is due to be completed by the end of June. 

Once complete, external views to the interior of House 7 will no longer be possible but a 3D photographic computer model is now available to allow visitors to remotely experience the interior in an intimate way not previously possible.  

Ann Marwick, monument manager at Skara Brae said: “Skara Brae remains popular with visitors from all over the world, and we hope the new 3D imagery of House 7 will add an extra interpretative dimension to their experience here.  Conserving these fascinating Neolithic remains is our top priority and the construction of this innovative new roof is a remarkable initiative.  We are positive it will be a great success.”