Calculate the volume of concrete needed for strip footings, trench fill, and pad footings. Enter trench dimensions and get instant volume, cost, and excavation quantities.
Calculate concrete volume from length × width × depth, with slab depth presets
Covers spillage, uneven sub-base, and over-dig
Strip footings are typically 225mm deep with a width of 600mm minimum. Trench fill is a full-depth concrete pour (usually 900mm-1m) that eliminates the need for brickwork below ground. Trench fill uses more concrete but is faster to build.
UK building regulations require footings to be at least 1m below ground level to reach stable subsoil. In clay soils or near trees, footings may need to be 1.5-2m+ deep. Always consult building control before pouring.
Most strip footings don't need reinforcement if the subsoil is stable. However, on clay, made ground, or near trees, reinforcement mesh (A193 or A252) is often specified by building control or a structural engineer.
The excavation volume is always larger than the concrete volume because you need working space (typically 150mm each side) and the trench may be deeper than the concrete pour. Order concrete based on the actual pour dimensions, not the excavation size.
V = trench_length × width × depth
V_total = V × (1 + waste%)
V_exc = trench_length × (width + 0.3) × (depth + 0.1)
cost = V_total × price_per_m³
Footings are structural and building-regulation controlled in the UK. Always consult building control and/or a structural engineer before excavation. Soil conditions, tree proximity, and nearby structures can all affect footing design. Never pour footings without building control inspection.
UK building regulations require footings at least 1m deep in stable subsoil. In clay or near trees, they may need to be 1.5-2.5m deep. Always check with building control before excavating.
Minimum 600mm for single-storey buildings, 750mm for two-storey. The width must be at least 3× the wall thickness. Consult building control for specific requirements.
At 600mm wide × 225mm deep: V = 10 × 0.6 × 0.225 = 1.35 m³. With 5% waste: 1.42 m³. At £120/m³: about £170. For trench fill at 1m deep: 10 × 0.6 × 1.0 = 6.0 m³ = £720.
Most strip footings on stable ground don't need reinforcement. On clay, made ground, or near trees, building control may require reinforcement mesh. A structural engineer can advise on specific cases.