Pre-design is the first phase of a design project. In this phase, the owner and architect establish design requirements and goals. Additionally, research is performed to analyze the site and local code and zoning requirements. This section describes several pre-design tasks, how BEM can be used to assist in the pre-design decision-making, and data gathering activities for the BEM practitioner to apply to models in later design stages.
Site analysis is the study of the climatic, geographical, historical, legal, and infrastructural context of a specific site. While many of these activities are performed by an architect or landscape architect, BEM practitioners can assist with the following aspects of the site analysis:
- Climate analysis - evaluate how weather conditions affect the site and help identify effective design strategies to ensure the building will be comfortable and will achieve the desired energy performance.
- Site conditions - evaluate how the site's location and surroundings may impact the design.
- Available utilities and fuel sources - determine if fossil fuel service is available at the site and if it's desired for the project or whether an all-electric design will be pursued. Determine if any clean energy electricity providers or tariffs are available for the project site if desired for the project.
Energy Code and Program Analysis
The U.S. Department of Energy's Building Technologies Program notes that "Energy codes affect the design of all building systems separately and collectively. Designing for energy efficiency can impact the look, feel, and function of the building. For example, lighting and window design can impact cooling loads, windows can impact lighting, and so on." It is important to understand which codes apply to the project and how they, along with any beyond-code programs, may influence the design.
BEM practitioners can assist with the following tasks:
- Determine the applicable energy code - identify the code and version in effect. Review mandatory requirements and the energy modeling procedures for the performance approach.
- Determine ventilation requirements - identify the ventilation code requirements and if additional ventilation is desired by the owner.
- Determine applicability of beyond-code programs - identify any additional energy modeling tasks or documentation are needed to comply with beyond-code programs (e.g. green building certifications, reach codes).
- Identify potential incentives - identify opportunities to achieve monetary incentives associated with using energy modeling in the project design process.
The programming process defines how a building will be used by the occupants, including how much area will be designated for different space types. Programming is typically not an activity that involves the input of an energy modeler, but the outcome of the program must be understood by the modeler as it will inform their analysis as the project progresses.
BEM practitioners should be sure to review the following aspects of the building program:
- Review space type percentages - determine approximate percentage of area associated with different space uses in the building.
- Identify any special space types - determine if any space types exist in the building that may need special attention given to modeling plug loads or HVAC systems.
The American Institute of Architects (AIA) Framework for Design Excellence notes that "[energy benchmarking and goal setting] is a critical first step for every project... benchmarks are easily shared with the design team and owner, and are a basis for a deeper conversation about how the building is intended to work. Everyone on the team should understand a project’s benchmark and its energy goals."
BEM practitioners are often instrumental in helping to provide this understanding to the team. Their role includes:
- Research performance benchmarks - review how similar building types typically perform in terms of energy use intensity (EUI), peak loads, carbon emissions, and other metrics.
- Set performance goals for the project - based on the benchmarking exercise, set a performance target for your project. As with the benchmarking analysis, these targets may be based on several different metrics.
- Determine renewable generation objectives - in addition to setting energy performance goals, projects may have goals for renewable energy production or procurement.
- Determine design/operation features required by owner (OPR)
- Site Evaluation as a Starting Point for Green Design - Article from BuildingGreen.com describing key components of a site evaluation (beyond energy impacts).
Links to external websites are provided as a convenience for further research, but do not imply any endorsement of the content or the operator of the external site, as detailed in BEMcyclopedia's general disclaimers.
- "Predesign services: Prepare for success with AIA Contract Documents".
- "Site Analysis". Wikipedia.
- "Building Energy Codes Resource Guide: Commercial Buildings for Architects" (PDF). U.S. Department of Energy. 2011.
- "Architectural Programming". Whole Building Design Guide.
- "Design for Energy". Framework for Design Excellence. American Institute of Architects.