Roadbase for a Parking Area

Creating a Heavy-Duty Parking Pad

Parking areas that will regularly support heavy vehicles, trailers, boats, or caravans need a more substantial base than a standard driveway. A compact parking pad of 5 metres by 3 metres provides enough room for most vehicles with some manoeuvring space. At 200mm depth, chosen for its ability to handle heavier loads and repeated use in the same location, you'll need approximately 3 cubic metres of DGB20 roadbase. This weighs around 5.4 tonnes, requiring bulk delivery from your landscape supplier.

The 200mm depth specified here exceeds standard driveway recommendations because parking areas experience concentrated loads. Unlike a driveway where vehicle weight moves across the surface, a parking pad has tyres stopping and turning in the same spots repeatedly. The extra base thickness prevents these stress points from developing ruts or sinking over time.

Site Preparation for Heavy Loads

Heavy vehicle parking demands thorough site preparation. Excavate to remove all topsoil and organic material, reaching stable subsoil that will support the loads above. If your subsoil is clay or becomes soft when wet, consider excavating deeper and incorporating a geotextile fabric layer to prevent the roadbase mixing with the underlying soil. This separation layer significantly improves long-term performance on challenging ground conditions.

Compaction Requirements

For parking areas supporting heavy vehicles, thorough compaction is essential. A plate compactor handles most residential applications, but for best results on heavy-duty parking pads, consider hiring a small vibrating roller. Compact in layers no thicker than 100mm, wetting the material to optimum moisture content before each pass. Test compaction by driving on the finished surface and checking for any movement or deformation. The surface should feel completely solid under load.

For a gravel top surface over this base, see our gravel parking area calculator. Use our main roadbase calculator for different dimensions.