Properties of coal ash foamed brick stabilised with hydrated lime-activated ground granulated blastfurnace slag

•Coal ash and hydrated lime-activated GGBS for fabrication of bricks.•Hydrated lime is necessary for GGBS activation and acceleration.•The addition of foam for weight reduction influenced the properties of bricks. Industrial by-products are significant to be used as raw materials and binder for fabrication of building materials to substitute dwindling natural resources and polluted binder. Brick specimens composed of coal ash as raw materials and stabilise with hydrated lime-activated ground granulated blastfurnace slag (GGBS) as binder system were fabricated. Foam at different percentage was incorporated during mixing to provide lightweight effect. The compressive strength, density, flexural strength, water absorption, salt attack resistance, thermal conductivity, sound transmission loss and sound absorption tests were carried out. The effect of binder and incorporation of foam to the properties of bricks were studied. The results show that there are significant relationships established.