Building Energy Resilience

June 2022 update: Given the current supply chain and labor shortages the construction industry is facing in 2022, looking after your building's existing systems becomes even more important. With equipment delivery for major systems sometimes many months away, retrocommissioning your existing systems can help tune them up to keep them in tip-top shape to get more usable -- and efficient -- life out of them. 

When people ask me what I do for work, I generally tell them I’m a building systems engineer, with a big focus on making facilities more energy efficient and comfortable for occupants. One common part of my job entails going to a building to perform an energy audit or assessment. During these visits, we follow the same straightforward outline:

1. Walk through the site
2. Inventory all energy-related equipment including lighting, mechanical systems, building envelope, etc.
3. Speak with the building operator about how they run the building
4. Ask the building owner, occupants, and operator about and any issues or concerns they have regarding maintenance, equipment that is not working properly, or comfort problems.

Through these visits, we produce a report that documents not only the existing building systems, but recommendations on equipment upgrades or operational changes that can be made to save energy or improve comfort. We also provide quantification of energy and cost savings for each identified opportunity so that the building owner knows how much of a bang they get for their buck.

In a previous blog post, I discussed the energy benchmarking service we currently perform for a healthcare network using the Energy Star Portfolio Manager (ESPM) tool. This tool is used to monitor the energy usage of a building over time. It allows a user to set energy goals, compare the overall energy use intensity (EUI) to a baseline year, and compare the building in question to other buildings with similar use-types and characteristics. In addition to continuing this specific service for the healthcare network, Cx Associates uses the benefits of benchmarking in other areas of our work too. This blog post will discuss what other areas of our work utilize benchmarking and then provide a brief update on changes ESPM has made to their scoring metrics over the past year.

Sometimes certain parts of the commissioning and retrocommissioning process can seem trivial to both the contractor and the commissioning agent. Of course, the process involves some important and significant checks, such as ensuring the piping design detail matches the as-built piping, and that the specified ductwork sizes match the as-built ductwork size. But the commissioning process also deals with some of the finer details that may not seem as consequential or that have already been checked by multiple parties. So, why would the commissioning agent also need to check it again? In this post I am providing a couple examples of real-world commissioning issues that we’ve found. Each is an excellent reminder of why the seemingly minor commissioning verification steps are still required and important, even though they may seem inconsequential.

Retrocommissioning (RCx) or Existing Building Commissioning refer to a technical process that retrofits and tunes building HVAC control systems so that buildings function more efficiently and effectively. The RCx process has historically included three primary phases: Planning, Investigation, and Implementation.

As the newest engineer to join the Cx Associates team, I have had the immense pleasure to be able to approach buildings from a different angle than in my previous work experience. In my former work as a mechanical design engineer, the focus was on current building technologies and keeping up with the most cutting-edge designs for our systems and buildings. Don’t get me wrong, looking to the future of efficient building technologies is tremendously important, but as someone who is concerned about the current state of the environment and ensuring there’s a habitable world for generations of living things to come, I found it hard to believe that new buildings alone are capable of being more than a small drop in a big bucket. After all, there are only a small number of new buildings built each year compared to the vast existing building stock. A quick look at the numbers from the Commercial Buildings Energy Consumption Survey (CBECS) by the US Energy Information Administration (EIA) will tell you that of the total data set, only about 18% of commercial buildings were built in the most recent 12 years surveyed. (https://www.eia.gov/consumption/commercial/data/2012/bc/cfm/b8.php)