Sustainable earth walls to meet the building regulations

• DOI: 10.1016/j.enbuild.2004.08.005
• Publication Date: 2004-10-05T11:09:06Z
• Authors: Steven Goodhew; Richard Griffiths
• Keywords: Thermal transmittance; Cavity wall

The thermal conductivity and diffusivity of un-fired clay bricks, a straw clay mixture and straw bales have been measured using a thermal probe technique, with an iterative method for data analysis. The steady-state air-to-air thermal transmittance, or U-value, and the time-dependent thermal properties of some proposed sustainable earth wall constructions are presented. Sustainable cavity walls of un-fired clay bricks with paper, straw or wool cavity insulation have thermal transmittances less than 0.35 W/m2 K, and therefore meet the current United Kingdom Building Regulations. A review of possible methods for thermally up-grading existing earth walls, by adding an internal insulated timber frame construction, again demonstrates possible compliance with the current UK thermal regulations.