Applicability of Autoclaved Aerated Concrete (AAC) blocks compared to conventional bricks and blocks within the Sri Lankan context

Abstract

Autoclaved Aerated Concrete (AAC) blocks have gained increasing attention as a lightweight, energy-efficient, and sustainable alternative to conventional masonry materials. However, despite the growing demand for faster and environmentally sustainable construction practices, AAC block utilisation within the Sri Lankan construction industry remains limited due to low awareness and uncertainty regarding its applicability. Therefore, this study aims to assess the suitability of AAC blocks compared with conventional bricks and concrete blocks in terms of quality and time efficiency within the Sri Lankan context. A mixed-method research approach was adopted through a systematic literature review, questionnaire survey, and semi-structured interviews. Quantitative data were collected from 92 construction professionals using simple random sampling and analysed using Statistical Package for the Social Sciences software, while qualitative data were gathered from ten industry experts selected through purposive sampling and analysed using content analysis. The findings revealed that only 47.8% of respondents were aware of AAC blocks, indicating a considerable lack of industry awareness. Nevertheless, AAC blocks were identified as superior in terms of lightweight properties, thermal insulation, reduced labour requirements, faster construction, and environmental sustainability. Compared with conventional bricks and blocks, AAC blocks significantly reduced construction time due to their larger size, fewer joints, and absence of curing requirements. The study concludes that AAC blocks represent a viable and sustainable alternative for the Sri Lankan construction industry, although greater industry awareness is required for wider adoption.