Planning to Reopen an Unoccupied Building – Considerations for Your COVID-19 Safety Plan: FACS Update #3


Shelter-in-place orders, social distancing, working from home, and other epidemic response guidelines implemented on the Federal and State levels can result in secondary issues in commercial buildings such as offices, restaurants, and businesses that may have been vacant or minimally occupied for extended periods of time (i.e., more than a few days). Need for additional building space to provide temporary housing or medical care is also a concern during significant public health emergencies.

As these orders are gradually lifted, businesses come back online, and workers begin to return to work, or when occupying previously vacated buildings for surge capacity support it is critical that building-related issues be identified and addressed to ensure the continued health and safety of people who begin to reoccupy these spaces.

Issues that may arise that should be considered prior to re-opening a building for occupancy include, but are not limited to:

  1. Potable and Non-potable Water Stagnation. Reduced or minimal usage of water systems during periods of low occupancy can lead to water stagnation or lack of flow. Water stagnation can create issues with water quality including microbial growth of organisms like Legionella and Pseudomonas, leaching of lead and other metals, and build-up of particulate or sediment.
  2. Mold & Moisture Events. Flood, rain or other water intrusion events that occur in unoccupied buildings may have gone unaddressed, resulting in water damage or mold growth.
  3. Indoor Environmental Quality. Degraded indoor air quality can be caused by lack of ventilation and circulation of fresh air during low or non-occupancy, which can result in the buildup of indoor air and surface contaminants such as dust and particulates and volatile organic compounds.
  4. Food & Chemical Expiration. When buildings have reduced or no occupancy for extended periods of time, especially when the expected duration of low occupancy is unknown and can’t be anticipated, items such as food, chemicals, and products can expire. The consumption of expired food or use of expired chemicals or products can result in both health and safety issues and quality issues.
  5. Pest Control. Standard preventive maintenance such as pest control activities are often postponed or halted altogether in unoccupied buildings. Reduced or minimal maintenance activities can allow for infestation of pests or accumulation of pest allergens, dander, and droppings that can impact indoor environmental quality. Pest waste such as bird and bat droppings can also contain infectious agents, which can pose a potential exposure and health hazard for occupants.
  6. Cleaning & Disinfection. In the current pandemic situation, there may be concerns regarding the health status of building occupants or visitors who may have accessed a building or business prior to building closure. The potential contamination of surfaces or equipment is likely to be of high concern for occupants re-entering the building and starting up work processes. Enhanced cleaning and disinfection procedures may be necessary prior to building re-occupancy as a precaution to address any contamination with agents of concern, such as SARS-CoV-2 (Coronavirus).
  7. Other Health & Safety Issues. A variety of other health and safety issues can arise in buildings that are left unoccupied. These issues can include but are not limited to electrical and fire safety, unknown odors, hazardous materials spills, and security concerns.

Prior to reopening or occupying a building following extended periods of low or no occupancy, it is essential to perform a comprehensive risk assessment to identify health and safety issues that may impact building occupants. This risk assessment can then be used to develop and implement a plan to address and correct any issues identified. Consider clear, proactive communication with occupants regarding building health and safety upon re-occupancy to address occupant concerns before they escalate.

The experts at FACS recommend careful planning, consideration, and correction of potential health and safety issues that can arise in unoccupied buildings before businesses return to full functionality. We hope these considerations help you and your organization put in place a plan to support the safety of your people and stakeholders during this challenging time. We will continue to provide updates with information and experiences we feel may help. Please contact us if you have any questions or if our experts can be of assistance in managing your response.


Megan Canright, MPH, CIH
Director of Scientific Operations