Concrete Footing Calculator - Cement & Foundation Calculator

Cement is the binding powder ingredient, while concrete is the complete mixture of cement, sand, gravel, and water used for footings. When using a cement footing calculator, you're actually calculating concrete requirements. Concrete mix ratios for footings: 1 part cement : 2 parts sand : 3 parts gravel (C20-C25 strength). Pre-mixed bags contain all ingredients. Our concrete footing calculator shows both ready-mix volume and bag quantities. For DIY footings, 25kg cement bags make approximately 0.012m³ finished concrete. Always use "concrete" not just "cement" for structural footings - cement alone has no strength without aggregates.

UK Building Regulations require minimum footing depths based on soil type and structure. Strip footings for houses: 450mm minimum depth below ground level in good soil, 600-900mm in clay or poor soil. Pad footings for garden structures: 300-450mm depth. Width requirements: strip footings minimum 600mm wide for single-storey, 800mm for two-storey buildings. Depth must reach below frost line (450mm UK minimum) to prevent heave. Always dig to undisturbed ground. Use our cement footing calculator to estimate concrete volume once you've determined correct dimensions. Consult Building Control for load-bearing structures - depths may need to increase for heavy loads or poor ground conditions.

Bag quantities depend on footing volume. Example calculations: 2m³ strip footing = 160 bags (25kg) or 100 bags (40kg) or 67 bags (60kg). Small pad footing 0.5m³ = 40 bags (25kg) or 25 bags (40kg). Formula: divide volume (m³) by bag yield - 25kg bag yields 0.0125m³, 40kg yields 0.02m³, 60kg yields 0.03m³. Our concrete footing calculator automatically shows all bag sizes and recommends most economical option. Bulk ready-mix is cheaper for footings over 2m³. Add 5-10% wastage for foundations. UK builders typically use 40kg bags for footings as best balance between handling weight and coverage. Order extra bags as concrete cannot be left incomplete overnight.

UK standard concrete strength for footings: C20 minimum (20 Newton/mm² compressive strength) for domestic foundations, C25 for heavier structures. Ready-mix specification: GEN3 for foundations and footings (equivalent to C20). Bag mix ratio: 1:2:3 (cement:sand:gravel) achieves approximately C20 strength. For exposed footings or poor ground, use C25 or higher. Sulfate-resisting cement required in high sulfate soils - check ground conditions. Foundation concrete must meet BS 8500 specifications. Our concrete footing calculator estimates volume only - always specify correct strength grade when ordering. Foundations are critical structural elements - use proper foundation mix, never weaker paving or general purpose mixes.

Most concrete footings require steel reinforcement for structural integrity. Strip footings: 2-3 lines of 12mm rebar running length, 50mm from bottom. Pad footings: mesh grid of 12mm bars both directions at 200mm centres, or A252 mesh. Trench fill foundations may not need reinforcement if filled to 1m depth minimum. UK Building Regulations specify reinforcement for stepped footings, footings on slopes, or poor ground conditions. Minimum concrete cover: 75mm all sides for foundations. Position rebar on spacers before pouring - never lay on ground and lift. Engineer calculations required for commercial structures. Our cement footing calculator provides concrete volume - consult structural engineer for reinforcement specifications based on loads and ground conditions.

UK concrete footing costs vary by method and volume. Ready-mix concrete: £100-£140 per m³ delivered (minimum charge applies for small loads under 4m³). Bagged concrete: £4.50-£7 per 25kg bag = £360-£560 per m³ (more expensive but convenient for small footings). Labour costs: £150-£300 per day for groundworker, foundations typically 2-5 days depending on size. Example project: 3m × 0.6m × 0.5m strip footing = 0.9m³ costs approximately £100 concrete + £300-£600 labour = £400-£700 total. Use our concrete footing calculator for instant material cost estimates based on current UK pricing. Bulk delivery cheapest for volumes over 2m³. Include excavation, hardcore base, and building control fees in total budget.