Westbrook Primary School

Noise pollution caused by passing aircrafts was a major problem for Westbrook Primary School, due to its location under one of the main flight paths for Heathrow Airport. The issue was exacerbated during the summer months when windows needed to be opened to allow for ventilation in the building, causing disruption to learning.

As part of major new construction works taking place at the school, consulting engineers WSP worked closely with Polypipe CGU and BSRIA to devise an innovative ventilation solution that minimised the environmental impact while limiting noise pollution.

A modular earth tube structured wall pipework system utilising Polypipe CGU’s market-leading Ridgistorm-XL large diameter pipe was installed as a ground source energy system to precondition the temperature of incoming air before it enters the building, with air drawn into the earth tube system via air inlets. This passive technology enables the transfer of ground source energy to heat or cool ventilation air, stabilising temperatures without compromising the learning environment.

Earth tubes operate on the understanding that earth temperatures are relatively constant throughout the year at just a few metres below ground. In Summer, the soil around the pipe will be cooler than the atmospheric air, so the pipe will deliver cool, fresh air to the school. Conversely, in Winter, the soil will be warmer than the atmospheric air, so the pipe will deliver warm air to the school, reducing its heating bill.

The system, which is comprised of 376 metres of Ridgistorm-XL in 900mm and 1050mm diameters, allows 100% fresh air ventilation within the school, creating an improved internal environment, while reducing the energy required to heat or cool the building and greatly reducing the school’s carbon footprint in line with the requirements of the 2011 London plan.

Polypipe CGU’s Ridgistorm-XL with electro-fusion was selected for a number of reasons. As well as the smooth internal lining of the pipework reducing resistance of air movement through the tubes, the external corrugated profile of the tubes also increases the surface area of the pipe wall, increasing the temperature transfer efficiency.

Despite its large size, the lighter weight nature of the system made it easy to handle and install, providing substantial health and safety benefits against the use of traditional concrete pipe systems.

Polypipe CGU was also able to fabricate Ridgistorm-XL condensate chambers off-site at its manufacturing facility in Loughborough to reduce and remove water from the system. The system also incorporates an anti-microbial lining to resist the development of bacteria in the system and ensure the safety of pupils and staff.