The more knowledge the consultant has of the operational performance of the building he or she is designing, the more likely a successful outcome, says Dr Alan Jones. Ian Vallely reports.
As things stand, building services design is predominantly a sizing industry. However, size isn't everything, as Dr Alan Jones, who heads up building design software developer Environmental Design Solutions Ltd (EDSL), acknowledges: '[Building services] is orientated towards getting the right sized kit in. However, on top of that, there is a critical need for good operational performance in order to produce buildings that are actually going to work.'

He adds: 'You can find situations where a building is designed to be quite energy efficient and has interesting building controls logic, but isn't understood at the commissioning stage or downstream at facilities management...

'By modelling the controls and the performance of the equipment, you recognise the efficiencies and innovation in the technology and, as a consequence, you will probably have to spend less on compliance.'

The big challenge facing the hvac sector in the coming five years is, Dr Jones believes, to ensure that the design intent becomes a practical reality. He explains: 'That requires a lot more knowledge and understanding of the design intent of the building as it moves through construction into commissioning and facilities management... If our intent is truly to reduce the CO₂ emissions in the built environment, the building has to work, and that means tackling the issues at concept stage.'

This has significant cost implications. Dr Jones again: 'If the building is efficient and the demand profiles are small and gently varying then the kinds of systems you can put in for control are simpler and therefore probably more cost effective.'

Overcooked engineering

However, keeping it simple requires a deep understanding of the system. Dr Jones believes that much engineering is overcooked 'to cover all the aspects which we may not understand clearly enough'.
Many technologies that are important for low CO₂ emissions have fairly long paybacks. For Dr Jones, the art of good design is finding the ingredients that are the most cost effective for the client: 'That is what the people who use our software are particularly interested in. It is a fundamental task of the designer to optimise the investment.'

But there is more to optimising the investment than simply analysing the payback. It also requires a fundamental shift in working practices, as Dr Jones acknowledges: 'It is important that the architect and the engineer work together. This is as important as the person who runs the building understanding how it works. Traditionally, the relationship between the architect and engineer has been dreadful. This has to change.'

This is, however, easier said than done; the four-year time span allowed for CO₂ emissions to drop by 60 per cent is insufficient for a cultural change to take effect, according to Dr Jones.

Nonetheless, he believes change is inevitable: 'The traditional way has involved the architect producing the drawings and the design of the building and he hands these on to the engineer who will then fit it out with pipes and ducts and everything else that is needed. Engineers have not been used to talking at the concept stage, but they need to.'

Good feedback quickly

However, in order to talk to the architect in a meaningful way, the engineer needs a design environment that gives him or her the correct feedback quickly. Dr Jones again: 'We are talking about doing some fancy calculations here. If you take one room with all its plant and controls and so on and you simulate that for a whole year hourly, [the software] takes one second. It's not slow.'

When EDSL gets involved in consultancy, it is inevitably at concept stage, bridging the gap between the architect and the engineer. This is a critical role to ensure that the design intent is met. He offers this example of how things can go wrong: 'We have looked at a number of projects where the design intent has been value engineered out.

High quality engineering

'For example, there have been naturally ventilated hospitals where, rather than a centre pivot window to allow the stack effect and efficient ventilation, they have become top hung with a 200mm limitation on opening meaning that the space is starved of air. Nobody thought that through from concept to delivery - somewhere along the line the concept was lost.'

EDSL's role in consultancy depends on high quality engineering. Indeed, in Dr Jones's view, this is critical if the building services sector is to thrive. And, he adds, if it embraces high quality engineering, there is an important payoff in terms of attracting the brightest and best into the building services sector: 'I see a fundamental change in the quality of engineering in this country. Actually delivering seriously low CO₂ buildings is going to sort the plumbers from the engineers.

'People are being asked to design. The engineer is no longer a catalogue animal; rather, he is a design engineer and I think that will attract more high calibre people into the industry.'