•  
  •  
 

Abstract

The construction sector faces increasing pressure to reduce embodied carbon and adopt circular material strategies, with bio-based materials offering a promising pathway. Straw-based insulation, particularly in loose-fill form, has gained traction in Europe, where several products have achieved certification under EAD 040138-01-1201. This study investigates the potential of Irish-processed straw chip as a bio-based insulative infill for framed construction by evaluating its material properties and thermal conductivity–density performance relative to European ETA-certified reference products. A programme of laboratory testing was undertaken on commercially available Irish straw samples, including material characterisation (moisture content, particle morphology, and dust content) and thermal conductivity measurement across a range of densities. Results indicate that Irish straw exhibits properties within reported ranges for certified materials. Thermal conductivity values of approximately 0.040–0.045 W/(mK) were achieved at densities of approx. 100 kg/m3, consistent with the performance envelope of ETA-certified products. Comparative and independently verified testing further demonstrated similar thermal performance at matched densities. The results reinforce the central role of bulk density as a governing parameter influencing thermal performance and as a proxy indicator of broader behaviour. While no fire testing was undertaken, achieving target densities associated with fire resistance provides indicative support for further investigation. Although limited in scope, the findings suggest that Irish-processed straw has potential as a low-carbon insulative infill. Further accredited testing is required to support certification, particularly in relation to fire, moisture, and durability performance and blow in application.

Download

Share

COinS