Vacancy is an unavoidable reality in commercial real estate. Between lease expirations, tenant buildouts, and market downturns, every property manager will manage empty spaces at some point. While the lost rental income from vacancy is obvious and closely tracked, the utility costs associated with vacant spaces receive far less attention. This is a costly oversight. Vacant spaces continue to consume electricity, gas, and water at levels that can be surprisingly high, and without active monitoring, these costs accumulate unnoticed until they show up as unfavorable variances in quarterly operating reports.
Understanding and managing vacancy utility costs requires a different approach than managing occupied-space costs. The goal is not optimization in the traditional sense but rather cost containment: ensuring that vacant spaces consume only what is absolutely necessary to maintain building integrity and lease-readiness, and flagging any consumption that exceeds those minimums for investigation.
Why Vacant Spaces Still Consume Utilities
A common misconception is that an empty space should consume no utilities at all. In practice, there are several legitimate reasons why vacant spaces maintain a baseline level of consumption, and understanding these drivers is essential to distinguishing between expected and problematic usage.
HVAC and Climate Control
Most commercial buildings cannot simply shut off HVAC to a vacant space without consequences. In cold climates, maintaining a minimum temperature is necessary to prevent frozen pipes, which can cause catastrophic water damage and affect adjacent occupied spaces. In humid climates, running dehumidification prevents mold growth that would require expensive remediation before the space can be re-leased. Even in moderate climates, completely shutting off air circulation can lead to stale conditions that make the space unappealing during tenant tours.
The key is setting HVAC to vacancy mode rather than turning it off entirely. Most building automation systems support unoccupied setpoints that maintain minimum temperature and humidity thresholds while dramatically reducing energy consumption compared to occupied-mode operation. A well-configured vacancy setpoint might maintain temperatures between 55 and 85 degrees Fahrenheit and humidity below 60 percent, using a fraction of the energy required for occupied comfort conditions.
Lighting and Electrical Systems
Emergency lighting, exit signs, and fire alarm panels continue to draw power regardless of occupancy. Security systems, including access control panels and surveillance cameras, also maintain constant loads. In some buildings, elevator systems serving vacant floors continue to operate and consume standby power even when the floors are not in use.
Beyond these essential systems, there are often non-essential loads that continue to run in vacant spaces simply because no one has turned them off. Plug-in devices left behind by previous tenants, bathroom exhaust fans set to continuous operation, and decorative lighting on timers are all common sources of unnecessary consumption in vacant spaces.
Water Systems
Water consumption in vacant spaces should be near zero in most building types, but it rarely is. Running toilets, dripping faucets, and malfunctioning ice makers left behind by tenants can generate continuous water consumption that goes undetected for months. In buildings with cooling towers, the tower continues to operate based on building-level heat load, and the water consumption associated with evaporation and blowdown is allocated across all spaces regardless of occupancy status.
Establishing Vacancy Baselines
The foundation of effective vacancy cost management is a well-defined baseline that represents the expected utility consumption for a vacant space. This baseline serves as the reference point against which actual consumption is measured, and any deviation triggers an investigation.
A vacancy baseline should be established for each utility commodity and should account for the specific characteristics of the space and building. Factors that influence the baseline include the size of the space, the HVAC configuration, the presence of dedicated meters versus shared building systems, and the climate zone. A 10,000-square-foot office space in Phoenix will have a different vacancy baseline than the same-sized space in Minneapolis due to the different HVAC requirements for maintaining safe conditions in each climate.
Building the Baseline
- Identify all meters and submeters serving the vacant space. Determine which meters are dedicated to the tenant space and which serve shared building systems that will continue to operate regardless of vacancy status.
- Document all systems that must remain operationalduring vacancy, including HVAC vacancy setpoints, emergency lighting, fire protection, and security systems. Calculate the expected energy consumption for each system based on manufacturer specifications and operating schedules.
- Shut down or disconnect all non-essential systems and equipment. Walk the space to identify any plug loads, lighting circuits, or equipment that can be safely powered down without affecting building integrity or compliance.
- Monitor consumption for 30 days after completing the shutdown to establish the actual vacancy baseline. This observed baseline will be more accurate than a calculated estimate because it captures the real-world performance of building systems in vacancy mode.
- Set alert thresholds at 10 to 15 percent above the established baseline. Any consumption that exceeds this threshold should trigger an automated notification to the building engineering team for investigation.
Flagging Unexpected Consumption
Once a vacancy baseline is established, the monitoring system should continuously compare actual consumption against the baseline and flag deviations. The most common causes of unexpected consumption in vacant spaces fall into several categories.
Equipment malfunctions account for a significant share of vacancy consumption anomalies. HVAC systems that fail to transition to vacancy mode, or that cycle back to occupied settings after a power interruption, can consume three to five times the expected vacancy baseline. Water heaters that continue to maintain temperature in spaces where no hot water is needed waste energy continuously. Building automation system schedules that were configured for the previous tenant and not updated for vacancy can keep lighting and HVAC running on occupied schedules.
Unauthorized access is another source of unexpected consumption. In some markets, vacant spaces are used by building staff for storage, staging, or break areas, which introduces consumption from lighting, personal devices, and HVAC adjustments. While this use may be harmless, it inflates vacancy costs and should be documented so that it can be accounted for in the baseline or eliminated if the consumption is material.
The most expensive vacancy consumption anomaly is also the most preventable: water leaks. A single running toilet in a vacant restroom can waste over 70,000 gallons per year. In a space that no one visits regularly, the leak can persist for months before appearing as an anomaly on a utility bill.
Shutting Down Unnecessary Services
A systematic shutdown checklist ensures that every unnecessary utility service is deactivated when a space becomes vacant. The checklist should be executed within the first week of vacancy and verified by a building engineer who walks the space to confirm compliance.
- HVAC: Switch to vacancy setpoints. Verify that the BAS schedule reflects unoccupied mode for all zones serving the vacant space. Disable demand-controlled ventilation overrides that might increase airflow based on CO2 sensors detecting building staff passing through the space.
- Lighting: Turn off all non-emergency lighting circuits. Disable occupancy sensors that might trigger lights when maintenance staff enter the space. Remove or disable any decorative or accent lighting left by the previous tenant.
- Water: Shut off water supply to the tenant space at the isolation valve if one exists. If the space shares water service with other tenants, close individual fixture shutoffs for all sinks, toilets, and appliances within the space.
- Gas: If the tenant space has a dedicated gas meter or gas-fired equipment such as a kitchen hood or supplemental heating, shut off the gas supply at the meter or isolation valve.
- Plug loads: Walk the space and unplug or disconnect all non-essential equipment. Check for refrigerators, coffee makers, space heaters, and other devices left behind by the previous tenant.
Financial Impact and Portfolio-Level Strategy
The financial impact of unmanaged vacancy utility costs is often underestimated. Consider a 50,000-square-foot office floor that becomes vacant. If the space consumes electricity at $2.00 per square foot per year during vacancy (compared to $4.50 during occupancy), the annual electricity cost for the vacant space is $100,000. A well-managed vacancy program that reduces consumption to $0.80 per square foot saves $60,000 per year on that single floor.
Across a portfolio with multiple vacant spaces, these savings compound quickly. A property management firm with 500,000 square feet of vacancy across its portfolio could be spending $1 million per year on vacancy utility costs that could be reduced by 40 to 60 percent through systematic baseline management and shutdown procedures.
Conduit helps property teams manage vacancy utility costs by automatically detecting when a space transitions from occupied to vacant status, establishing consumption baselines, and alerting building engineers when consumption exceeds expected levels. The platform tracks vacancy costs separately from occupied-space costs, giving asset managers clear visibility into the true carrying cost of empty spaces and the financial impact of vacancy reduction efforts.
The most effective vacancy cost management programs treat utility monitoring as an integral part of the vacancy management workflow, not an afterthought. By building shutdown checklists, baseline monitoring, and anomaly alerts into the standard operating procedure for tenant move-outs, property teams can ensure that vacancy costs are minimized from day one and that unexpected consumption is caught before it becomes a material budget variance.