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What To Do If Your Building Has Partial Occupancy During COVID-19

If some of your tenants have implemented a work from home policy and your building occupancy is now significantly reduced, you have a unique opportunity to curtail costs and reduce energy usage over the coming weeks and months. But where do you start? Our team of building systems experts has compiled a list of best practices to help you adjust operations during COVID-19. Check out our webinar for even more detailed advice from our team and an expert from Cushman & Wakefield.

Communicate with Your Tenants

Now, more than ever, it is important to communicate with your tenants and keep them apprised of changes in the building. To get a sense of the daily comings and goings within your building you should regularly poll tenants to determine anticipated occupancy schedules. 

After receiving occupancy plans from your tenants, we recommend at least 4 touchpoints to ensure that all stakeholder needs are met.

  1. Notify tenants of any planned changed to the building schedule and request their feedback/permission to proceed.
  2. Follow up. Plan for 1-2 follow ups; many tenants are not likely to respond right away.
  3. Communicate your plan of action and confirm you have a clear understanding of tenant requirements.
  4. Notify tenants that the changes are taking place effective immediately.

Identify Occupied and Unoccupied Areas Within the Building

For occupied tenant spaces, consider elevated ventilation rates to increase the effective dilution ventilation per person (as system capabilities allow). Be prepared to allow tenants to request air conditioning as needed. Based on the feedback you get about their occupancy schedules, you may be able to modify your startup and shutdown times or rotate building loads by cycling run times between different floors. 

For completely unoccupied tenant spaces, consider running on a relaxed schedule (e.g. +/- 5 to 8 degrees), continuously monitoring temperature and humidity level. Humidity is particularly important, an upper limit of 60% relative humidity is reasonable. If you exceed that for long periods of time, you risk promoting mold growth.

For either scenario, it is important to understand the outdoor air design of your buildings. Knowing the rates and system capabilities (fixed vs. variable OA systems) will allow you to make even more tailored adjustments.

Document Planned Changes

Our current reality highlights the importance of having accurate and complete documentation around your building operations. You may be working with backup engineers or in shifts that are spread out. A written sequence will come in handy for all the people making operational decisions about the building. 

Be sure to document your building’s existing sequence of operations as well as the planned changes. This will ensure that you can track the impact of your efforts, keep all stakeholders aligned, and make it easier to return to normal operations when the time comes.

While you’re at it, we recommend taking the chance to assess the current state of your building by doing the following:

  • Take stock of major building and control systems
  • Take stock of controls sequences (e.g. SAT Reset, Duct Static Reset, economizing, scheduling, etc.)
  • Understand limitations of building
  • Understand relevant codes
  • Review deferred maintenance and bandwidth to complete

When it’s Time to Resume Normal Operations

Ensure that your building is healthy and well operated before all your tenants return.

Per ASHRAE Std 189.1-2017, there are two extremes for preparing a building for occupancy. For new construction, ASHRAE dictates a 14-day flush out. For existing buildings, it dictates one hour of ventilation when a space has been unventilated for 24 hours. 

You can expect your preparation efforts to fall somewhere within that range. We recommend that you begin preparation at least 2-3 days before reopening. Be sure to ask tenants for a 1-3 day notice ahead of their return in order to get the space ready. 

During your reopening preparation, return building schedules and setpoints to normal operations and verify all equipment is running properly. Consider flushing out for 1-3 hours a few times a week.


Be sure to consult the CDC, OSHA and ASHRAE, and any local or federal guidelines along with these best practices.

Additional resource: ASHRAE Guidance for Building Operations During the COVID-19 Pandemic 3/24/2020