Can you guarantee that the completed building will match the performance predicted by the analysis in its day-to-day operations?
- Why or why not?
I don’t think so—there are too many real-world variables that could throw off the predictions. Building performance analysis is based on models and assumptions, but actual operations are affected by factors like weather, occupant behavior, maintenance quality, and equipment failures in unexpected ways. Even small changes, for example like a tenant leaving the lights on all night or HVAC systems being manually adjusted, could impact energy use. However, good design and commissioning can help bridge the gap, even though there will probably always be a difference between predicted and actual performance. I think the goal is to get as close as possible, but expecting a perfect match isn’t realistic.
When choosing settings for each of the building performance factors, should you always choose the setting that gives the absolute lowest predicted energy use?
No, not necessarily—energy efficiency is important, but it’s not the only factor that matters. For example, comfort, cost, feasibility, and long-term maintenance play a role in selecting performance settings. For example, maxing out insulation might reduce energy loss, but it could also increase construction costs and introduce moisture problems if not designed correctly. As another example, aggressive daylighting strategies could lower energy use but might cause glare and make workspaces uncomfortable. The best approach I think is to balance efficiency with other design priorities in order to make sure the building performs well in a way that makes sense for the people/tenants using it.
4D simulations are often used to show the construction sequence for an entire project, but shorter simulations that focus on a specific period of time are also useful.
- Can you provide examples of how a simulation that focuses on a 1 or 2 week period could be useful for planning?
A shorter (like 1- to 2-week) simulation could be useful for pinpointing very particular construction activities and coordinating teams more efficiently. In other words, they can provide a more detailed look at specific construction phases which makes them easier to optimize. For example, if a major concrete pour is scheduled, a short-term simulation could probably be useful for helping to plan staging areas ortruck deliveries to prevent bottlenecks. It can also help identify specific clashes in scheduling, like ensuring structural steel installation doesn’t overlap with plumbing work in the same space. Another example would be planning the installation of any prefabricated components—you would want them to arrive just in time to avoid storage issues while keeping assembly on track and not delayed due to late arrival of those prefab components.