UK buildings are routinely being over-designed with 50% more electrical capacity and 30% more heating and cooling capacity than they will ever need, a study has found.
The study by engineers at Ramboll found commoditised or ‘play it safe’ design was rife in the UK construction industry to cut design costs.
Ramboll experts have calculated that, when applied to the 11.8 million sq ft of offices currently under construction in London alone, this over-design is costing the UK £70m in capital expenditure and 23,000 tonnes of CO2 per annum. This is based on estimated achievable savings to be in the region of £60/m in capital expenditure and up to 50% in both energy savings and carbon emissions.
The analysis showed that this is often down to the industry over-designing in its efforts to ensure compliance with current codes and guidance, inadvertently resulting in excessive building system capacity due to a significant gap between predicted performance and reality
In addition, under-pressure building designers are commoditising and re-using ‘safe’ off-the-shelf design element, compounded by a procurement system that stifles innovation by focusing overwhelmingly on price. This may cut design costs but adds to the inefficiency of the finished buildings.
Ramboll said that its analysis was based on the studied operational energy performance of more than 100 commercial properties, using real life data. In working to deliver leaner designed buildings, Ramboll has been using lessons learned from engineering in extreme environments. Working together for the first phase of the Rothera Modernisation Project, Ramboll and the British Antarctic Survey developed a design that targets a reduction in energy consumption by up to 35%. To support this they developed a parametric modelling tool called the Evolutionary Energy Solver that processes millions of possible scenarios and mimics nature to identify the combination of inputs that will provide the best performing, or ‘fittest’ solution. This reduced the time needed to identify these ‘fittest’solutions by 88% and demonstrated that all possible solutions had been considered holistically.
Ramboll UK managing director Mathew Riley said: “Over-design is wasting capital investment for building owners and driving higher energy consumption for building occupiers. Nobody wins”.
“The key to efficient design is to really understand how a building will perform, by simulating its operation early in the design development, allowing more informed decisions to be made. At Ramboll we learned from our work, engineering building in extreme environments such as the Antarctic, methods that we are now working to apply back into the UK so that we can deliver leaner and greener systems”.
“We need to break free from outdated delivery models and conventional thinking. By embracing data driven design the industry can reduce capital expenditure, cut carbon emissions, reduce energy consumption and deliver leaner and more sustainable buildings”.
Andrew Henderson, Ramboll executive director for UK buildings, added: “Our analysis shows that in the UK, designing to current codes and guidance and pressurised consultants commoditising and re-using ‘safe’ designs, often with only minor adaptations from previous projects – is resulting in massive inefficiency. The reality is there are smarter ways to achieve, and indeed, exceed compliance standards without increasing capital expenditure.
“Outdated procurement approaches is also stifling progress. Price is of course still the key factor in determining conract awards, and so innovation is rarely encouraged or recognised. The full capabilities of talented engineers in our industry are not being harnessed by the market and there is little prospect of improving industry productivity unless something changes”.