AAC Blocks vs. Brick — Best Choice for Kerala Construction

The choice of wall masonry material is one of the most consequential decisions in residential construction — it affects the structural performance, thermal comfort, acoustic quality, and overall cost of the finished building. In Kerala, the two dominant options are conventional burnt clay bricks and autoclaved aerated concrete (AAC) blocks.

Conventional burnt clay bricks have been used in Kerala construction for over a century. They are locally produced, widely available, and familiar to every mason in the state. A well-made ISI-marked class 1 brick provides a compressive strength of 7.5 N/mm² — adequate for most residential masonry applications. The limitation is variability: brick quality varies significantly between manufacturers, and the high water absorption of poor-quality bricks contributes to damp walls and efflorescence.

AAC blocks are manufactured under precisely controlled conditions with consistent strength, dimensions, and density. The aerated structure — created by introducing hydrogen gas during production — gives AAC blocks a thermal conductivity of 0.16 W/mK, compared to 0.6–0.8 W/mK for conventional brick. In practical terms, AAC block walls in Kerala maintain indoor temperatures 3–5°C lower than brick walls of equivalent thickness — a significant benefit in the state's hot and humid climate.

Cost comparison: AAC blocks cost approximately ₹45–₹55 per block (equivalent to 7–8 conventional bricks). When the reduced mortar consumption, faster construction speed, and lower structural self-weight — which can reduce foundation and structural frame costs — are factored in, the overall wall construction cost with AAC blocks is typically 8–12% higher than brick but delivers measurably better thermal performance. For all framed RCC structures in Kerala, we recommend AAC blocks as the preferred infill wall material.