Concrete Volume Calculator
Calculate the exact volume of concrete for slabs, paths, driveways, and pours. Get results in m³, bags, and ready-mix quantities.
As an Amazon Associate and CJ Affiliate publisher we earn from qualifying purchases. Prices and availability may vary.
Concrete Slab Guide
What do I need to know about 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.
What's the difference between Ready-Mix and 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.
What's the key thing to understand about 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.
What's the key thing to understand about 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 Gas Safe registered engineer — it is illegal for anyone else to carry out gas work in the UK, and using an unregistered installer invalidates both your home insurance and any warranty on the work. For structural changes (removing load-bearing walls, altering the roof structure), always get a structural engineer's assessment before starting, even for jobs that look straightforward.