When a building is found to be consuming excess energy, the next step is usually an energy audit followed by retro-commissioning of the HVAC system. If available, an infrared scan of the building exterior might follow. Perhaps these steps will quickly pinpoint the problem. While these tools are great to have, consulting engineers should not forget that their experience and thought processes are the most valuable tools for accurately diagnosing and fixing the problem.

When you are called by the building owner or manager to figure out the source of the energy “leak,” how can you ensure your differential diagnosis will be complete and your final report accurate? While it might be easy to rely on building information systems to identify the problem, what will you do if this technology is not present or functional? Even when automated systems are in place, valuable time and dollars can be wasted on non-specific tests that may not be necessary. Instead of taking a rote approach, you can use complete yet flexible thinking to rapidly diagnose and correct the problem.