What is a sub-base?
The sub-base is a compacted layer of aggregate material, typically MOT Type 1, laid beneath paving to distribute loads and provide stable structural support.
A sub-base is the foundational layer of compacted aggregate material installed directly on the ground before paving is laid on top. It acts as a buffer between the soil and the finished surface, spreading the weight of vehicles, foot traffic, and weather across a wider area. This prevents the paving above from cracking, sinking, or becoming uneven as the ground shifts or settles.
In Cheltenham driveways and paths, contractors typically use MOT Type 1 (recycled crushed stone and brick meeting Department of Transport specifications) as sub-base material. The aggregate is compacted in layers to create density and stability. Proper sub-base thickness varies by use: residential driveways usually need 100-150 mm, while heavier-traffic areas require more.
A well-prepared sub-base is essential for long-term durability. Poor or missing sub-base preparation is one of the main causes of premature pavement failure, including cracking and surface deterioration. Water drainage through the sub-base also matters, as it prevents moisture pooling that can weaken both the base and the paving itself.
When getting quotes from driveway paving contractors, ask what sub-base material they use and how thick they lay it. Quality varies significantly between contractors, and a properly installed sub-base often determines how long your paving lasts.