Ask anyone in the construction industry about foundations, and they will tell you that they are the most important part of a building. Yet when it comes to reducing energy in the built environment, foundations have, up until now, been overlooked.
â€˜The majority of people donâ€™t think about foundations because they are hidden in the ground,â€™ said Prof Saffa Riffat, head of the Institute of Building Technology at Nottingham University. â€˜So when they talk about low carbon buildings, people talk about the buildings themselves, the windows and the doorsâ€¦but in fact energy use of foundations is massive.â€™
Riffat, who is also president for the World Society of Sustainable Energy Technologies, has worked with construction company Roger Bullivant Ltd to develop a modular house foundation system known as â€˜System Firstâ€™. The process is designed to replace traditional trench-fill foundations using prefabricated steel beams that lay across concrete piles. These piles are covered with polystyrene slabs which are then covered with a layer of concrete screed to create a lightweight and insulated floor slab.
â€˜System First provides a floor which is suitable for use in homes of the highest sustainability standards due to its exceptionally low heat loss through the floor,â€™ explained Riffat. â€˜It uses significantly less concrete and raw materials than traditional flooring construction and has lower embodied CO2. The floor slabs also have minimal heat transmittance which reduces the buildingâ€™s energy requirements and CO2 emissions.â€™
The System First technique is claimed to achieve an 88 per cent saving in water, a 75 per cent reduction in construction time and a 92 per cent saving in raw materials; foundation which would conventionally use 233 tonnes of cement can be reduced to 18 tonnes. The concept Â has already been demonstrated in a wide range of projects including in the BASF House, the Mark Group House, and the Solar Decathlon House at the Nottingham University Institute, in the Llanelli School extension, and in Buckshaw village in Lancashire.