Dr. Don McLean, Founder and CEO, Integrated Environmental Solutions (IES) (November 2011)
The rules for building used to be fairly straightforward. Architects and engineers were focused on one thing - production. How quickly and cheaply could they build a beautiful looking building?
The tough decisions architects and engineers now make are inextricably linked to energy - both its reduction and its source. A building is no longer just a combination of shapes and forms; it represents the efforts to dramatically reduce our carbon footprint.
According to Lord Kelvin, "If you can't measure it, you can't improve it." Stated another way, "If you can't quantify, then you are guessing." So the question becomes, how can we quantify?
Building performance analysis is a vital component in designing truly sustainable buildings. By using technology to calculate the impact of different design strategies, architects and engineers can make more informed decisions on elements that play an important role in reducing the energy consumption of a building. Performance analysis software allows designers to virtually test the feasibility of different energy-saving strategies and new low-carbon technologies that facilitate very efficient high-performance designs.
A sustainable, energy-efficient design requires an understanding of how a building will perform under predictable circumstances. This is what performance analysis delivers. It looks at how climate impacts on performance and can be used as a resource, determining usage and comfort criteria; driving decisions about building site, form, and organization; and investigating the most appropriate design strategies (daylighting, natural ventilation, shading, etc.), as well as the most appropriate materials.
Unfortunately, building performance analysis is too often only undertaken in the later stages of design compliance rather than incorporated into the process right from the earliest architectural design stages. By working together and utilizing building performance analysis software from day one, architects and engineers can make the biggest impact in terms of designing a sustainable building.
Performance analysis as a function needs to be integrated into the design process as an integral part of the project, and ideally should continuously advocate for better energy performance at every step of the way. Different activities and tools must be brought to the table at different stages. There are several ways to split the division of labor, from integrating its consideration into architects' and engineers' job functions or introducing an independent function to the design team. Regardless of how the team is formed, it's essential that it is part of an integrated design process.
Call to Action
Conceptual performance analysis is the idea that the impact of design can be understood even before the shape of the building is defined - at the earliest stage of a project. The results from performance analysis provide indicative actions, not predictive ones. If the key drivers are identified early in the process, the chance of error or missed opportunities later in the design is greatly reduced.
In order to reach carbon-neutral levels by 2030, for example, designers need to have access to intelligent building information in the earliest stages. Imagine being able to determine which floor-to-area ratio is most energy-efficient before geometry or room layout is considered? Or imagine having access to information on seasonal weather patterns, theoretical energy required in order to achieve occupant comfort, and bio-climatic responsive design suggestions based on the coordinates of your building.
What if determining a starting point and focusing on your conceptual design using these performance indicators as guidance is all you need to help your team quantify and form energy-saving strategies, while still keeping design integrity? Imagine tying in checks against LEED targets at key stages from schematic design onward, thereby guiding and focusing decisions to take design performance into consideration alongside the LEED rating - the goals can often be conflicting. And, if you need to make decisions about tradeoffs, wouldn't you feel better if they were based on facts rather than guesses?
All this is now possible, but architects and engineers need to work together to incorporate lean, clean, and green into the process as a core concept.
Lean: Using climate-responsive design to make passive and hybrid strategies part of the solution and reduce energy requirements
Clean: Applying low-carbon technologies where appropriate
Green: Leveraging renewable technologies to a higher degree because the energy requirements of the building are now greatly reduced
Performance analysis guides this by identifying and understanding the big issues related to building energy use and performance, which supports the setting of realistic energy goals and the ability to choose and design strategies to reach these.
For the full impact of performance simulation to be realized, early analysis must continue throughout the entire process to design completion and beyond. Detailed analysis can provide accurate figures and results for system sizing, fine-tuning, compliance, costing, and documentation. However, the key point is that because the foundations are strong, the design can now be refined to achieve greater efficiencies as it progresses - rather than today's all-too-familiar situation, i.e., trying to fix energy-related issues in the concept, when it's impossible and too costly to go back to the drawing board.
By implementing indicative actions based on performance analysis metrics, and identifying the key drivers for an energy-efficient foundation early in the design process, i.e., by quantifying, true sustainable design can be achieved.