Arc Architects

This project tested the variety and weathering of traditional Scottish earth construction in a programme designed to fill the knowledge and skills gap in the conservation of vernacular earth structures. Arc were principal authors of the final report, to be published by Historic Scotland TCG.

A wide-ranging programme of more than 230 tests was carried out on sample walls at 3 external sites, representing different climatic conditions. The tests assessed a diverse range of forms of construction, material mixtures, additives, fibres, coatings and finishes.

Monitored for 7 years, the results highlighted the importance of good grading for long-term durability of earth materials and documented an incompatibility of lime coatings to earth substrates due to differential movement.