Concrete Volume Calculator
Calculate the exact volume of concrete for slabs, paths, driveways, and pours. Get results in m³, bags, and ready-mix quantities.
Concrete Slab Guide
Correct Depth by Use
Garden path (pedestrian): 75–100mm. Patio (pedestrian): 100mm. Domestic driveway: 100–150mm with hardcore base. Garage floor: 150mm. Vehicle crossing: 150mm reinforced. Shed base: 100mm. Always lay on a compacted hardcore sub-base of 75–100mm.
Ready-Mix vs Bagged
For volumes over 0.5–1 m³, ready-mixed concrete is more economical and consistent. Minimum ready-mix orders are typically 1 m³. Under 1 m³, use bagged ready-mix concrete (25kg bags make approximately 0.012 m³). Hiring a cement mixer makes large bag mixes much easier.
Reinforcement
Domestic garden slabs don't typically need reinforcement. Driveways should use A142 mesh (steel fabric) for vehicle traffic. Any slab subject to differential settlement (tree roots, poor ground) benefits from mesh. Lay on polythene DPM and allow 28 days before loading.
Safety and Regulations
Most structural and electrical DIY work in England and Wales must comply with Building Regulations and is notifiable to local Building Control. Work that is not notifiable (like-for-like replacements, cosmetic changes) can be done without notification. Notifiable work done without approval is technically illegal and can cause problems when selling the property. Electrical work in most rooms requires a Part P competent person or Building Control inspection. Gas work must always be performed by a
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