Life cycle assessment for masonry exterior wall assemblies made of traditional building materials

Abstract

Building materials contribute a significant amount of CO2 to overall greenhouse gas emissions and this environmental impact should be reduced to improve the sustainability of the construction industry. Although new and low-carbon materials are emerging, the majority of materials used are still traditionally produced and are highly carbon intensive, such as masonry blocks and insulation slabs – rock wool or expanded polystyrene. To assess which of the traditionally used building materials are more sustainable, in this paper, wall models of the most widely used masonry blocks and insulation materials were analysed using life cycle assessment. The wall models were created to fulfil the requirements of nearly-zero energy buildings. The assessment showed that the lowest impact on the environment is from aerated concrete blocks and expanded polystyrene insulation, which is mostly due to low weight and raw materials consumption compared to other materials. On the other hand, expanded polystyrene insulation poses more danger to humans and the environment in its use phase than other materials due to emissions during fire and degradation, thus should be used with caution.

Hempcrete – CO2 Neutral Wall Solutions for 3D Printing

“…These walls are to 614 mm thick and emit 83.41 to 146.71 kg of CO2 eq. [21]. The comparison shows that the results obtained in this study align with other studies on the GWP of hempcrete materials and that such bio-based self-bearing envelope and thermal insulation building materials have significantly lower CO2 emissions than traditionally used wall materials.…”

“…Impact for 1 m 2 of the wall with the defined U-value is calculated using 'cradle-to-gate' system boundaries. For comparison with the traditionally used materials, previous studies have been used, where walls with brick blocks and polystyrene layer [20], aerated concrete and insulated reinforced concrete [13], various insulated masonry block constructions [21] have been used.…”

Sustainable Wall Solutions Using Foam Concrete and Hemp Composites

“…It must be mentioned that traditionally used wall blocks have a significant environmental impact [11], mostly due to using cement as a binder [12]. The use of fibrous bio-composite material is one way to reduce the environmental impact of wall blocks [13].…”