Galliford Try is managing the £8.9 million project to demolish the existing Westbrook Primary school and rebuild a new sustainable building on a different part of the site. The project has been awarded funding from the Government’s Climate Change Technology Strategy Board towards the pioneering research and implementation of building methods that will protect the school against predicted changes to climate over the next 100 years.
Situated just two miles from Heathrow and directly under the flight path, the school site poses some difficult energy efficiency, acoustic and thermal challenges. Pollard Thomas Edwards specified the Thrutone fibre cement slates for the main two-storey section of the school, not only for the roof but also for vertical cladding, to help address these demands.
Jordan Wang, Project Architect from Pollard Thomas Edwards, comments: “Westbrook Primary School is seeking to run a low energy building that also minimises ongoing maintenance and running costs. We chose the Thrutone fibre cement slates for their sustainability, cost and low maintenance benefits which meet the school’s criteria perfectly. Using the slates vertically has enabled us to create continuity between the roof and facade and create a striking design for the main building. The school has been designed using innovative building methods to ensure that not only is it resilient to climate change but also that it can be adapted in the future if necessary.
“The main design challenge for this project is its position under the Heathrow flight path, which creates obvious acoustic issues for the school operation, especially if windows need to be opened in classrooms, so we needed to find a natural ventilation method to avoid overheating. The primary way of doing this was with an underground thermal labyrinth to provide outside air to classrooms. The use of fibre cement slates as cladding also helps to protect the building from the elements, as well as contributing to the overall sustainability targets.”
Cllr Tom Bruce, cabinet member for education and children’s services, explains: “For our schools in Hounslow, the constant drone of planes flying overhead can be hugely disruptive to learning. The age of many of the buildings means that when it gets warmer in summer, simple things that are taken for granted elsewhere like opening windows aren’t possible. Soundproofing, ventilation and insulation become much more difficult – and costly – when we are trying to expand schools, so it’s vital we work with the acoustic and engineering experts to meet the needs of each different school.”
Charlotte Hughes, Product Manager from Marley Eternit, adds: “We are seeing increasing interest from specifiers in using fibre cement across the whole building envelope because of its design flexibility and sustainability credentials. As we start to see more extremes of weather in the UK, it is important that developers consider future proofing their roofs and buildings and we are proud to have been involved in such a pioneering climate change project.
“A key benefit of using Thrutone fibre cement slates is that they are naturally secure through design with a low profile leading edge which incorporates both a nail and rivet fixing, which means they could help to protect against the extremes of wind and rain expected over future years.”
Thrutone is a market leading lightweight fibre cement slate offering superb aesthetics with its blue black colour, smooth surface and square cut edges. Intensive testing at Marley Eternit’s research and development centre has proven that with a reduced rafter length of 4m, the Thrutone slate can be used at a lower pitch of 15°.
As part of Marley Eternit’s fibre cement range, Thrutone boasts industry leading sustainability credentials, including a low carbon footprint of just 13 CO2e /m² (based on 600 x 300 slate at 100mm lap), certification to the BES 6001 standard for Responsible Sourcing and the ability to achieve the lowest environmental rating (A+) in the BRE Green Guide. Fibre cement also offers sustainability benefits throughout its whole life cycle, as it can be fully recycled at the end of its use. Waste fibre cement can be ground down and used to replace limestone and shale in clinker production, the essential ingredients for Portland cement.