Material Density Reference — kg/m³

Material density is essential for: calculating structural loads (dead loads for beam and foundation design), estimating material quantities by weight when ordering (aggregates, soil), determining transport requirements (vehicle load limits), checking floor load capacities, and calculating volumes from known weights. For example, knowing that concrete is 2,400 kg/m³ tells you that a 150mm slab over 20 m² weighs 7,200 kg (7.2 tonnes).

Bulk density includes the air voids between particles — it is the density of the material as it would be delivered and placed. For loose materials like sand and gravel, the bulk density is less than the solid density because of the air gaps. Compact (rammed) materials have a higher bulk density than loose-tipped materials. The values in this table are typical bulk densities for construction use.

Multiply density (kg/m³) by thickness (in metres). For example, a 100mm (0.1m) thick concrete slab at 2,400 kg/m³ weighs 2,400 × 0.1 = 240 kg/m² (or 2.35 kN/m² as a design load). This is useful for calculating floor dead loads, wall self-weight, and foundation loads. To convert kg/m² to kN/m², multiply by 0.00981.