Assessment of the energy and carbon embodied in straw and clay masonry blocks

A.D. GONZALEZ

Eco-efficient Masonry Bricks and Blocks: Design, Properties and Durability

ELSEVIER SCIENCE SA

Año: 2014; p. 488 - 507

The manufacturing of wall blocks with straw and clay by small enterprises is introduced, and energy and carbon embodied assessed. These ecological burdens are compared to fired clay bricks and concrete blocks commonly used in the region of study. The technique has been used to built houses and large public buildings. It comprises the advantages of using local materials and working force with the addition of improved thermal efficiency. The benefits of constructions with renewable and local resources include: social benefits from local labour and businesses; lower impacts and recycling at construction and demolition; increasing resilience; adaptation of materials and techniques to local requirements; and mitigation of environmental impacts as energy and carbon footprints. Nevertheless, the high relevance of the operational phase in buildings should be carefully considered when local renewable materials are chosen. If energy and carbon emissions during the operational phase were high, advantages of lower embodied impacts could be compensated in short periods of time. The case study shown in this chapter clearly depicts that embodied energy and carbon for straw and clay blocks are much lower than conventional fired clay bricks and concrete blocks, and provide nearly 3 times better thermal resistance. Even larger differences in embodied burdens are found when a layer of insulation is added on conventional walls to make the comparison on equal thermal efficiency basis. On the other hand, when using straw, the sustainability of agricultural soils is important; this is also investigated in this chapter.