The requirements of people must shape our buildings’ designs, and joined-up engineering is the tool that offers the solution.
In today’s evolving business environment, balancing the often conflicting needs of building project stakeholders can be a tall order. “The building owner wants people packed to the perimeter; the developer wants acres of sexy glass; the facade and mechanical engineer would prefer a no-people zone; while Environmentally Sustainable Design (ESD) principles aim to achieve decreased energy usage,” explains Martin Smith, Aurecon’s Global Mechanical Service Leader and National Green Building Expert.
“The days of silo engineering are over, and that it’s become essential for project teams to synergise around a common focus: that of designing better buildings for people,” says Steve Daniels, Technical Director at Aurecon.
Steve: I believe the occupants of buildings have become more sophisticated. They are aware that they do not need to accept anything less than comfortable, efficient and even reactive working and home environments.
This new age of enlightened workers places a demand on employers to provide these working environments and, in turn, a demand on engineers and developers to make them available.
Joined-up engineering is the process by which these spaces are realised.
Martin: It is an extremely pertinent question which, for many years, curtailed green engineering because its many benefits are often intangible, or too long-term in nature to quantify. A focus on occupant comfort has in the past been subject to the same perceptions. As Steve has mentioned, there is a growing realisation around the importance of this type of investment. Using Computational Fluid Dynamics (CFD) to understand the efficacy of a building’s facade and HVAC system, for example, could be deemed as costly. However, this has to be put into the context of the overall cost of a building. Getting a building specification wrong is catastrophic and can easily result in a loss of use of 10% of lettable area.
Modelling is getting cheaper and more accurate. An experienced design team will be able to utilise past experience on similar projects, and apply these principles to the modelling process to ensure it’s as optimal as possible in order to maximise return on investment.
Steve: As well as the engineering being more readily available, there is an end-user demand for comfortable, reactive spaces. If employees demand the space, employers have to provide the space so that they maintain and attract top quality staff. Employers see the positive benefits in productivity and staff retention and are therefore willing to pay a premium for this type of building, creating a business case for the developer to design and produce these assets. The fact that the buildings are more efficient and cost effective to run and offer environmental savings, which are also marketable, is a side benefit of these efficient designs.
Martin: The starting point for good design is getting the basics right at the very start of the design process. The building’s orientation and the shape and type of the building envelope are foundational inputs that will influence the other components of a project. Following on from this, all disciplines need to be closely aligned around creating the best possible space for people. Lighting, mechanical, electrical and facade design teams should all interact around the impact that the design of each of these has on each other.
Steve: Facade engineering has the potential to have the greatest impact on the quality of space and the ‘experience’ of a building. A great deal can be done to optimise the design of a facade; in collaboration with the other engineering disciplines.
In the past, ‘smart’ facade designs have been seen as too expensive but now, with the benefit of our sister-MEP disciplines and dynamic modelling, we are able to show the human comfort benefits of these designs and also the long-term cost savings that they will realise.
Martin: To illustrate this further, wind effects on glass are typically accounted for using standard values in a glass database. There is generally a poor understanding of wind effect in spite of the fact that it can easily mean a 25% differential in glass temperature. If you do not understand this, how can you size the HVAC correctly?
Previously, we might have designed to achieve a comfortable 23 degrees, plus minus one degree, but we now know the importance of comfort, which is actually a combination of room temperature, humidity, radiation from glass, air movement and metabolic rate.
When you move closer to the facade, you can be exposed to radiation that cannot be compensated for by merely overcooling. In this instance, joined-up engineering would help balance the many factors that influence comfort when sitting near the facade, including the effects of cooling and accounting for blinds, external shading and lighting. In this way, it’s possible to ‘future-proof’ a design and avoid unusable areas of the building with low occupancy comfort.
Steve: The technology required to realise human-comfort-based designs is no longer part of the future, it is here already and joined-up engineering allows us to create a business case for their use. Some examples are:
The desire to use such products exists, but we need to help clients justify the initial associated expenditure so that future benefits can be realised, and the building occupants have an environment offering levels of comfort and reactivity that they expect.
Steve: At Aurecon, our ESD and facade teams both form part of the Building Sciences Group. This structure facilitates a close relationship and enhanced interaction between these engineering teams. In this way, our Building Sciences Group acts as a single point of responsibility for the most important aspects of a building’s design. It sees our teams aligned around achieving people-focused, marketable buildings for which developers will be able to charge a premium.