Research

Practical research is vital in earth building and is the foundation for all our work at Rebearth.

There were no earth builders in Scotland when I started out in the 1990s so it was necessary to develop my craft skills elsewhere. While it is possible to learn a great deal from earth traditions that are thriving in other parts of the world we also need to investigate and embrace the historic diversity that is present in traditional localised practice suited to local conditions.

At Rebearth we can analyse materials and record the archaeology of earth buildings, carry out field tests, make samples and organise laboratory testing of earthen fabric. We also innovate with new uses for old materials and we collaborate with other research partners to share our expertise and experience.

In short we strive to carry out research that will increase our knowledge base and improve how we build and repair with earth.

The Earth Structures, Renders and Plasters Project

The ESRP, conceived by the late and great Bruce Walker at Historic Environment Scotland, was the perfect opportunity to explore how earth and natural building materials might have been used in the past.

We carried out over 100 field tests using different building soils, techniques, additives and finishes at four locations in Scotland. These tests were monitored for 7 years. Perhaps the most surprising result was the durability and workability of all earth walls tested given the harsh extremes of the site conditions. It underlined the huge diversity of building materials that would have been available to Scottish vernacular builders.

The detailed results of this work are available here.

Soft capping research

We have been working with Arc Architects to develop techniques using native plants and clay mortar to conserve masonry.

Soft cappings can reduce moisture ingress and protect structures from surface erosion and frost damage. It is a multi-disciplinary field of research requiring an understanding of nature and building conservation, and a site specific response to repair with local materials.  Gradually we are building a body of knowledge about the benefits of natural soft capping, when to preserve it, and how we can replicate it with new plants and materials to encourage long term protection of building fabric. This research has been published and can be found here.

New ways to use old materials

We are constantly striving to test and develop innovative and sustainable ways to use natural materials, including unfired clay bricks from the manufacturing industry, clay/hemp mixes for walls and plasters, seaweed in earth and lime mixes and earth mortars gauged with hot lime.

Relevant publications can be found in the links page.