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Technical: Reviewing cibse's conference proceedings raises the question of why architecture has nothing similar. Is such shared learning unnecessary?

The books of cibse's annual conference* reflect a profession working from a base of structured research - some 70 papers are featured. Not to mention cibse's design guides - sound enough to be cited in the Building Regulations. Can we conceive equivalent events at the riba, the rias, the riai? Where is the profusion of systematic studies - as distinct from architects' own accounts - of, for instance, form-making and buildability in architectural contributions to energy and environment, of what makes a good health centre, office or shopping centre, of architects' changing roles in procurement?

Of course, individual practices are developing ideas - enough to provide material for weekly journals like the aj as well as for the monthlies. But the broad picture is episodic, not systematically cumulative, not of a profession institutionalised to learn communally. Even when the riba had a president apparently attuned to this in Frank Duffy, nothing much changed.

All this may sound like an old argument, going back to the 1958 Oxford conference which sought to define architecture as a discipline, asking what, and why, is architectural research. What also makes the argument contemporary is today's changing context. Consumers/clients increasingly expect knowledge-based professions. Even an apparently research-based profession like medicine is having to re-evaluate its past research to pinpoint more closely the effectiveness, or not, of treatments in a movement called evidence-based medicine. In construction, the once-somnolent major contractors are increasingly co-operating with one another and with clients to research construction effectiveness and the use of it for communication between project partners. Whether to be research-based is not a question asked any longer across much of the industry. Nowhere is the situation perfect, of course, but most areas are at least moving. While architecture as an institution remains in the research slow lane, the influence of architects can only further diminish.

Integrated design

probe is a suggestive model for architectural research. It is a long- term project of in-depth (and thus expensive) revisits to buildings looking at why their energy performance is the way it is. It is evidently possible to research like this and avoid writs. If the buildings chosen are an uninspiring lot, the pattern of findings is building into a set of well- founded design guidelines, especially exploring design for building manageability.

The cibse paper on probe highlights some widespread energy-related problems:

building management time is usually in short supply

there is little sub-metering so little feedback to occupant organisations on the particulars of changing energy performance

more-highly serviced buildings can waste larger amounts of energy if they lack good management

internal heat gains are often overestimated at design stage

poor usability, performance and commissioning of automatic controls

all systems may switch on at times when few occupants are present

new techniques and technologies can be expected to cause problems - longer-term follow-up support of occupants is needed.

In a particular area such as natural ventilation, close scrutiny can reveal unrealised potential in systems. For example:

ventilation controls are seldom operated as intended

natural ventilation systems may require more management, yet be designed into building types where management is scarce, for example in education

occupants sometimes do not understand how systems work

automatic window controls may have no manual override. Generally, 'smart' controls can have a mind of their own

furniture layouts may inhibit use of controls such as blinds and windows

design may focus on public areas at the expense of areas used by staff.

From such observations from eight buildings, the authors come up with a series of strategic conclusions, including for:

briefing - set out clear strategic objectives and avoid too much complexity in the search for flexibility

design - 'designers are not users, though they often think they are'

construction - good-quality construction cannot be taken for granted - from airtightness to controllability

handover - keep on commissioning and monitoring. Passive systems take longer to commission, maybe all the seasons

facilities management - match the design to the fm resources

outsourcing management - ensure the performance feedback keeps flowing to the occupant organisation.

The office politics of control in shared spaces remains a source of conflict. For example, there are studies here of reactions to letting air in versus keeping the traffic noise out. One trial approach to managing the politics is voting for preferred office environmental conditions on occupants' desktop computers. This is for an air-conditioned building where voting outcomes could drive the building management system. The seeming attractions of democracy have to be balanced against the requirement for frequent voting, perhaps every hour, the reactions of those who may always lose the vote, and so on. A notional screen layout (see illustration) and rough pilot study have been completed. The next step is a trial in a building in use.

Ventilation

One increasingly popular approach is displacement ventilation, in which fresh air at a little below room temperature is released from low-velocity floor outlets. It forms a pool of relatively cool air at floor level. Warm objects - people and machines - warm the air near them, forming plumes of air, and the cool fresh air from floor level rises to replace it. In principle fresh air is used economically, only where it is needed. And a directional air flow should be effective in removing pollutants.

Studies are getting better at predicting performance. For example, there are limits to how far the air flow can be increased to deal with peak heat loads before the floor-pool effect is lost. And where there are suspended ceilings that are not well sealed, polluted air above them may leak back into the occupied space.

Displacement ventilation is often combined with chilled beams or panels to improve cooling. There are rumours of 'office rain', ie condensation forming on beams and panels and then dripping on occupants. Four case studies by the bre suggest that the uk risk is generally not great enough to warrant control strategies. Research on such strategies at bsria indicates that reducing humidity is likely to be an expensive option. Increasing water temperature a little can be effective, with limited consequent reduction in cooling capacity.

Engineer Max Fordham has reported that for both Bedales Theatre (with Feilden Clegg, aj 15.2.96) and the Contact Theatre in Manchester (with Short Ford), natural ventilation of the auditorium generally works well. Inlet air is precooled in a labyrinth of high thermal-mass masonry beneath raked seating, and rises from floor inlets through the auditorium by stack effect. However, there are some limitations. Big air-inlet openings are needed, sheltered from wind and noise, with air passing into relatively large cooling spaces with low air resistance. Sufficient height is needed to allow space for warm-air stratification above people's heads. There are clear diminishing performance returns from increasing the ventilation rate or thermal-mass capacity.

One inefficiency of stack ventilation is the lack of heat recovery, because usually conventional systems would slow the air flow down too much. One trial system puts heat pipes like a grillage across ventilation stacks - a promising idea.

A problem of natural ventilation in urban areas is combating external pollution. However, high pollution concentrations can be quite localised in time or place. High concentrations may be mitigated by minimising natural ventilation at particular times of the day, or relying on mechanical ventilation with filtration at critical times of the year. Locating air inlets in a courtyard at the back of a building rather than on the street can make a significant difference to pollutant concentrations.

Not forgetting . . .

bre studies to quantify preferred qualities of interior lighting, such as non-uniformity.

Development of national databases of non-domestic buildings and their broad energy performance, for testing national policy and energy-saving approaches to specific building types among others.

bre development of an energy performance index for non-domestic buildings. A possibility for future Building Regulations to parallel the domestic energy Standard Assessment Procedure?

Ice slurry used for cooling (like the chopped ice on the supermarket fish counter). Its advantages are using latent heat (compared with using cool water) and that it is pumpable.

Services component suppliers are being involved early in design by amec (it's not just baa), using two- or three-stage tendering.

bsria is trying to get a better measure of 'margins' used in engineering calculation (or, as we normally call it, 'overdesign').

Akin to thermal capacity, Arup has been using the moisture capacity of thick masonry for a paper archive in Jersey to stabilise humidity. The inertia is seasonal, rather than daily/weekly as for heat, so summer moisture may be transferred to winter as well as shorter-term variations smoothed out. Thick walls and the lack of windows and people help control temperature swings. Air conditioning is avoided. Design software has been developed. Humidity is more important than temperature for paper; air leakage needs tight control, here to one air change per day. So the approach is difficult to transfer to occupied spaces where ventilation requirements rather than humidity dominate.

Should existing domestic boilers have an mot test? A survey suggests many would not meet forthcoming ec standards for nitrogen-oxide emissions.

Interoperability (services system components with standardised interfaces for intercommunication) should lead to more-readily integrated systems. For example, linking lighting, door access and security for out-of-hours working. Or multifunctional sensors covering smoke, heat detection, fire, presence detection, photocells and environmental information. Scottish Hydro has pioneering installations.

bre is working on design tools to predict night ventilation performance.

Future cibse climate data sets will include possible climate-change scenarios due to global warming.

Air leakage is increasingly recognised as a significant energy issue in non-domestic buildings. bre is developing a computer-based air-eakage predictor using data from measurement of typical constructions and testing predictions against measured results. There is also a conference on airtight construction on 25 March - hosted by cibse of course, not the riba.

* cibse National Conference 1997. cibse Member Services, tel: 0181 675 5211. 2 vols. 600pp. £60 (non-members)

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