Passivhaus Schools:
Heat your campus using ‘kido-watts’

Devereux Architects, which specialise in sustainable design, has found that whilst there is much talk of sustainable technologies, most of them are bolt-ons such as wind turbines or photovoltaics

The problem is that this generation of renewable energy is expensive and, until the costs begin to fall, does not represent the most economic alternative. With this in mind Devereux Architects has recently undertaken a trip to Germany to assess world leading developments in energy efficient design.

Unlike the bolt-on approach favoured in the UK energy efficient technologies are, within the whole life of a building, very cost effective. In fact when bundled together in the right manner, they can achieve a seven-year payback and reduce energy use by up to 85%. Energy efficient design is so cost effective that in February 2003 the City Parliament of Frankfurt declared that, “all kindergartens and schools are to be of PassivHaus standard.”

The PassivHaus standard is suitable for both new and refurbished buildings, as testified by the 6000 or so PassivHaus buildings in Germany and Austria. With regard to refurbishment residential buildings, rather than offices or schools, have mainly benefited from the PassivHaus standard. If it were not for the fundamentally poor quality of teaching environments within many of the UK’s older education establishments, there is no practical reason why the standard could not be applied to existing buildings here.

Why hasn’t the UK adopted this level of energy efficiency yet? The truth may lie in the fact that the UK has never had voluntary energy performance standards that could be used to help focus the mind. Instead we have made do with building regulations, believing they are best practice.

Over the last three years Devereux Architects, which is a member of the AECB: The Sustainable Building Association, has been steadily researching how to design and construct projects to the exacting PassivHaus standard. In fact the practice is now onsite with a PassivHaus residential scheme and looks forward towards being able to transfer this knowledge to new schools.

Under the remit of the AECB’s CarbonLite Programme the PassivHaus standard marks step two of the three steps to Net-Zero Carbon development. Originally developed in Germany the PassivHaus standard reveals just how far behind certain European countries the UK is with regard to the advancement of energy efficient buildings. The basic premise is relatively simple though it has been refined substantially since the first UK passive solar school, St. George School, Wallasey, was built in 1962 and is now a listed Grade II* building. In this building the heating system was not used for the first 16 years but with now with a smaller student roll and CFLs a tiny boiler is used for three hours a day. In this case the incidental gains were originally about 50% solar energy, 34% incandescent lights, 16% students, but as the student numbers have fallen and new energy efficient light sources have been utilised the need for the heating system arose.

Compared to existing building stock the refined performance of the PassivHaus standard enables an 80% reduction in carbon emissions. The standard relies on super-insulated walls and windows and a well-sealed building fabric to reduce energy consumption. Its mechanical ventilation system provides excellent air quality, 100% fresh air, as well as a highly efficient ‘heat recovery’ system. The exceptional air quality helps to ensure that carbon dioxide levels are kept low within classrooms and lecture theatres, ensuring that students, and lecturers don’t begin to feel drowsy.

Reinvesting the 85% cost savings, delivered through reduced energy bills, across education facilities could be used to provide millions of pounds worth of support and resources for British schools, colleges and universities. Furthermore studies have shown that excellent daylighting, which is required to reduce energy use, reportedly enables improved productivity including a 21% increase in learning rate. Just think what this could do for helping to making the world a better place to live.

Applying the whole suite of PassivHaus concepts means that a building retains the energy from students’ classroom activities and uses it to heat the building. In a nutshell you could say that a school is heated by ‘kido-watts’ rather than the traditional measurement of consumed energy known as the kilowatt.

Solutions like the PassivHaus Standard offer a more efficient and realistic answer to reducing CO2 emissions than the government’s current plans to offset carbon rich energy by emphasising so called renewable energy technologies. PassivHaus technologies also help to avoid the complications that can arise when a renewable technology fails or breaks down.

There are currently no educational facilities in the UK that meet PassivHaus standards, and whilst architects and builders are learning skills to meet the anticipated demand, there is a long way to go.
As challenging as it is, for the time being the PassivHaus energy standard is the most realistic step towards a low carbon future. Whilst designing and constructing buildings to the PassivHaus standard requires vision from clients, the research undertaken by Devereux.



Notes on the author:
Mark Siddall is an architect and a Certified PassivHaus Designer. He is also the sustainability champion for Devereux Architects and has conducted detailed research into low and net-zero carbon technologies. In addition to being one of the practice’s lead designers, Mark also provides consultancy, project enabling and education for clients, design teams and constructors. Currently he working on what is understood to be the UK’s first major PassivHaus scheme (25 homes) and is providing consultation for the Riverside One Net-Zero Carbon development in Middlesbrough (a significant scheme for Bio-Regional Quintain).