Groundtrax CellPave 50 Extends and Reinforces Car Parking at Stourhead National Trust

Client: National Trust

Project: Car park extension and surface installation

Product: CellPave 50

Area installed: Over 6,000m²

Project overview

Groundtrax (now part of Green-tech) was approached by a consulting architect enquiring about a suitable car park surface for Stourhead, an impressive Palladian house with surrounding landscaped gardens and parkland, run by the National Trust.

The property was looking to expand its on-site parking capacity and was keen to explore a solution that would increase its parking provision by over 6,000m².

Working closely with the consulting architect, the property manager, and the wider supply chain, Groundtrax offered a range of cellular paver grades to meet the site's requirements. Throughout the discussions, it was clear that this busy visitor attraction needed a solution that would deliver a robust, durable and hard-wearing surface, so CellPave 50 was specified.

The challenge

The site required a surface solution that would:

• Support high visitor numbers and regular vehicle loading

• Provide a durable and long-term parking surface

• Offer a SuDS-compliant solution to help manage surface water

• Integrate with existing asphalt access roads

• Deliver best value based on performance, not just cost

The solution

CellPave 50 is a heavy-duty 50mm cellular paver designed for high load-bearing applications. It is one of the heaviest products of its type on the market and is widely specified on commercial projects.

At over 8.5kg/m², with a 5mm sidewall and a particularly strong tile connection, CellPave 50 provides exceptional strength and stability.

Although cheaper, lighter-grade products were assessed, it was evident that CellPave 50 offered the best long-term solution aligned with the client’s requirements, rather than opting for a purely price-based solution.

A key attraction of combining cellular pavers with traditional hard surfaces such as concrete and asphalt is the reduced requirement for traditional drainage infrastructure. At Stourhead, the access roads are asphalt, while the parking areas are formed using cellular pavers filled with gravel.

SuDS performance

When heavy rainfall occurs, traditional impermeable hard surfaces require drainage systems capable of handling sudden increases in runoff. In extreme conditions, these systems can quickly become overwhelmed, increasing the risk of flooding.

As a SuDS-compliant product, CellPave 50 has key characteristics that reduce the likelihood of flooding. Firstly, with a cellular paver, water drains directly into the ground rather than entering the drainage system. Secondly, as a gravel-filled grid, the pavers act as a mini attenuation tank, holding water in place and allowing it to slowly percolate into the ground

The outcome

The car park extension provided an additional reinforced parking area of over 6,000m². The solution delivered a robust, durable surface suitable for a high footfall visitor destination, while also supporting sustainable drainage and reducing the burden on traditional drainage infrastructure.

David Marsh, Category Manager – Ground Reinforcement and Ground Protection at Green-tech, comments, “Stourhead required a durable, long-term parking solution capable of supporting high visitor numbers while remaining SuDS-compliant. CellPave 50 offered the strength and stability needed for a busy visitor destination, while also reducing surface water runoff and the need for extensive drainage infrastructure.”