Getting real about sustainable schools
July 01st 2008

There is a need for post-occupancy assessments of schools says Roderic Bunn, BSRIA & Usable Buildings Trust

First it was energy efficiency, then it was sustainability. Now the incoming catchphase, striking terror into clients and design teams alike, is carbon neutrality. Precisely what carbon neutrality means in practice depends to whom you talk, and whether carbon offsetting is part of the deal.The UK Green Building Council is lukewarm on carbon offsetting (such as planting trees or trading carbon permits to offset carbon-dioxide emissions), but government departments have different ideas.

While Communities and Local Government (CLG) are aiming for zero-carbon via energy efficiency measures through the Building Regulations and the Energy Performance of Buildings Directive, the Department for Environment, Food and Rural Affairs (DEFRA) – the department that advises other government departments on their procurement and construction delivery – is taking a broader view.

In her submission to the House of Commons Committee of Public Accounts report: Building for the Future: Sustainable Construction and Refurbishment on the Government Estate, published in January 2008, Helen Ghosh, Permanent Secretary at DEFRA, was asked whether the government estate was on track to be carbon-neutral by the target date of 2012:

“Carbon neutrality does not mean zero carbon. It does not mean that there will be zero carbon emissions; it means that there will be carbon neutrality as a mixture of carbon emissions and carbon offsetting to the standards that we shall set after our current consultation.We shall aim to reduce our energy use as far as possible, and to reduce carbon emissions more generally, but we cannot set bounds.”

To a minister’s question “Are you saying that if you cannot achieve it within the buildings, you will pay for it by buying carbon offset?”, Helen Ghosh replied: “Absolutely.That is what carbon neutrality means.”

So, from the mouth of the Permanent Secretary at DEFRA,we have a definition of carbon neutrality as seen by the government department responsible for public sector procurement.What it probably means in practice is: “we will do the easy stuff through energy efficiency, but when it gets difficult, we will buy our way out of trouble.”

Do we need DEFRA’s definition of carbon neutrality? The situation in the schools sector is certainly desperate enough.Despite the £45 billion investment in replacing every secondary school in England, plus a pledge to renew or refurbish every primary school, the very limited number of post-occupancy assessments being carried out show energy use to be increasing, not falling.

The studies are generally finding that electricity use is up to three times the design estimates. Heating fuel is frequently in the range 60-120 kWh/m2, where design estimates are often very much less than this. For both electricity and fossil-fuel use, new schools are rarely meeting best practice levels of 2002, and are often no better than ‘typical’ practice. This is despite the adoption of allegedly sustainable technologies such as solar and PV panels, biomass boilers, low energy lamps, automatic lighting controls, computerised building management systems, rainwater recovery, and the odd wind-turbine.

The reasons for the under-performance are easy to spot. The more recent schools suffer from the poor integration of renewable energy systems (particularly biomass boilers) in addition to the familiar supply-side shortcomings of unreal energy targets, rushed and incomplete commissioning, lack of post-occupancy aftercare, and unmanageable complexity in many of the systems that new schools inherit.

The Usable Buildings Trust (UBT) gives over twenty reasons for the shortcomings. Perhaps the most fundamental are:

• Designers don’t count everything, but generally only the energy used by the fixed building services that fall within the scope of Part L of the Building Regulations. This not only leads to under-reporting, but also misplaced priorities through a lack of a sense of proportion.
• Design calculations are optimistic. While we are getting better and better at calculating low energy, we fail in practice to deliver it, because… …Things aren't put together properly: and this is often as much a design problem as a contractor’s problem.
• Controls don't work well, and are often difficult for occupants and managers to understand, particularly as the design intent is often poorly communicated to them, both explicitly and tacitly; and design expectations about user behaviour are often mistaken.

The buildings are unmanageably complicated. The result is that lots of things don’t work as intended and default to ‘on’ when they should be ‘off’.

Unfortunately, the renewables bandwagon is requiring designers to make buildings yet more complicated, with scope for even more unintended consequences. Despite the message from post-occupancy evaluation being one of keeping things simple, robust and reliable, and to do them well, designers are being told – nay almost forced – to be clever with energy-generation technology.

None of this has been helped by the government's jettisoning of the research base in building performance – something that was severely criticised in a House of Lords report in 2004. Where, for example, is the knowledge base to build our Schools for the Future? Not necessarily in the DCSF, which has reduced expertise in the Schools Capital Design Unit while responsibility has been exported to the government’s Building Schools for the Future (BSF) delivery vehicle, Partnership for Schools.

In turn, PfS has exported design excellence assessments to the Commission for Architecture in the Built Environment (CABE), which, in turn, appoints ‘enablers’ from the professional supply chain to check the design integrity of…the professional supply chain.

So how can BSF create a road-map for carbon neutrality? Here are some ideas from the UBT: Develop calculation methods that reflect real outcomes

Currently you can get much more credit for making energy-consuming equipment efficient (or adding energy-producing equipment) than from making the passive measures work properly.

Pay attention to high-energy special areas.

Such as server rooms, catering kitchens, and swimming pools. These often have massive potential for savings, and by attending not only to the building services, but also to the kit.

Change the service of design and construction teams

Encourage designers and builders (and sometimes the procurement departments of large clients) to engage with the performance of their completed buildings to understand much better what actually works in practice, using extended commissioning and professional aftercare, including performance monitoring and

system fine-tuning.

Prevention is better than cure

Try to get rid of energy requirements rather than add technology to meet them (such as huge areas of glass and shading).Where technology is added, it needs to be highly efficient and only to operate when needed.

We currently have the mad situation where designers get a bigger carbon credit for generating a kWh of electricity on site than they do by saving a kWh by good design. If we are forced to rush off into more flights of high-tech fancy and unmanageable complexity, it could push schools into a power-dive into unsustainability as the sector invests in all the wrong things.

Keep it simple and do it well

Encourage products and processes that make potentially difficult things simple to do. Simple does not necessarily mean low-tech; it means simple to use, with performance that the user can take for granted.

Controls that work

Controls are a simple-but-difficult problem. Controls are where the users and the building come together.

Strategically this should be seen as an architectural problem, not just hived off to engineers. Designers frequently procure control systems and user interfaces that prove dysfunctional in use.Greater emphasis should be put on designing manual and automatic control, monitoring and metering systems which are technically effective,and as simple as possible to use and to operate, with practical, effective, well-designed and informative management and user interfaces.

Graduated handover

Traditionally, construction simply produces new buildings, or alters old ones, and hands them over when they are ‘practically complete’. Construction professionals are rarely commissioned to follow-through afterwards, to pass on knowledge to the occupiers and management, and to learn from the experience themselves. Consequently, they don’t really understand what they’re delivering; they don’t understand what works, and what needs to be improved. That means the supply chain isn’t delivering the best value in new schools, nor improving the industry’s knowledge base.

Buildings are not like cars: they are not complete and ready to run as they come off the production line. They need testing,proving, running-in – sea trials if you like. In other words a form of graduated handover and aftercare period,where project team stay engaged with the client and end users until the school and its systems are running smoothly, predictably and sustainably. The process includes staff training, fine-tuning, performance monitoring and information sharing.

This ‘Soft Landings1’ process embodies a change in attitudes and practices. It aims to make briefing, design and construction more performance-driven. It takes proper account of how buildings actually work,and how people want to use them.

The multiplier effect

Designers need to exploit a multiplier effect of energyefficient design:Halve the demand,double the efficiency of the kit you use to meet the demand, and halve the carbon in the supplies. This will cut carbon-dioxide emissions to one-eighth of what they would otherwise be – without undue recourse to the technical complexity of renewables and other managementintensive systems, seemingly with the sole result of defeating their caretakers.

With demand reduced and efficiency increased, investment in renewables will also go much further and be far more cost-effective.

1Soft Landings are a project run by BSRIA with the Usable Buildings Trust and the Darwin Consultancy. For more details on the project and its outputs, go to www.softlandings.org.uk/

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