Energy waste occurs in most commercial properties. Rising utility rates, stricter carbon-reduction mandates, and heightened ESG scrutiny mean wasted kilowatts now translate into measurable cost increases and reputational exposure.
A commercial building energy audit can turn scattered utility data into a clear roadmap of savings, comfort, and compliance. Rimkus can help uncover the waste, quantify the opportunity, and turn insights into action.
What is a Commercial Building Energy Audit?
A commercial building energy audit typically tracks every watt, BTU, and dollar flowing through a property. Following ASHRAE’s Procedures for commercial building energy audits, auditors usually combine on-site investigation, utility analysis, and engineering modeling to expose inefficiencies and quantify savings opportunities.
Benchmarking energy use intensity against similar facilities while dissecting HVAC, lighting, and building envelope systems may reveal substantial avoidable energy costs. These savings can flow directly to the bottom line while reducing carbon emissions. The quantified reductions can support decarbonization roadmaps, ESG reporting, and net-zero commitments.
This engineering rigor typically separates comprehensive audits from simple energy assessments. Beyond identifying obvious fixes, auditors can calculate payback, ROI, and life cycle benefits for each energy conservation measure.
The Three Levels of Energy Audits (ASHRAE Framework)
The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) defines three levels of investigation in its standardized procedures:
- Level 1, the Walk-Through Assessment, is a high-level screening. Auditors typically spend a few hours on-site reviewing a year of utility bills, visually inspecting lighting, HVAC, and controls, and talking with operations staff. The deliverable is usually a short report highlighting obvious, low- or no-cost fixes with rough payback estimates. Since there’s no data logging or complex modeling, Level 1 may work when a quick snapshot is needed, budgets are tight, or the facility is straightforward.
- Level 2, the Energy Survey and Analysis, generally digs far deeper. Auditors inventory all major systems, analyze at least twelve months of utility data, collect spot measurements, and develop energy use breakdowns. Each energy conservation measure (ECM) can be modeled for costs, savings, and return on investment, potentially providing a prioritized action plan that lenders or incentive programs might accept.
- Level 3, the Investment-Grade Audit, is typically reserved for major capital projects. Auditors may install temporary metering, analyze building automation system data over multiple weeks, and create calibrated energy models that test interactive effects like simultaneous heating and cooling. Detailed contractor pricing and life cycle cost analysis can turn the final report into a financing package that may be suitable for performance contracts or large-scale retrofit financing.
Rimkus can perform all three audit levels, matching the approach to building type, funding horizon, and data requirements.
Step-by-Step Process of a Commercial Building Energy Audit
The commercial building energy audit typically involves eight stages.
1. Define Audit Objectives and Scope
Successful audits begin with clearly defined objectives and scope. Whether seeking lower operating costs, reducing carbon, meeting a new code requirement, or preparing for a major retrofit, these goals can dictate the depth of analysis, the systems examined, and the metrics tracked. Typical systems on the checklist might include:
- HVAC systems
- Lighting infrastructure
- Building envelope integrity
- Mechanical-electrical-plumbing (MEP) equipment
- Control systems
- Onsite renewable energy sources
Early conversations with owners, operators, and occupants can help ensure expectations are aligned and access issues resolved.
2. Gather and Review Building Data
Auditors typically assemble two to three years of utility bills, architectural drawings, equipment schedules, and maintenance logs. From those records they can calculate the building’s energy use intensity (EUI) and map consumption to occupancy schedules. Comparing these metrics to peer facilities may quickly spotlight outliers that deserve deeper investigation.
3. Conduct On-Site Inspection
Auditors generally conduct facility walkthroughs to verify operating conditions and observe occupant behavior. ASHRAE procedures call for envelope checks, system nameplate verifications, and spot measurements with data loggers, infrared cameras, and airflow meters.
Rimkus’s multidisciplinary team completes these surveys collaboratively. Mechanical, electrical, and envelope specialists work concurrently on site to ensure comprehensive assessment
4. Analyze Energy Consumption Patterns
During this phase, utility data typically gets disaggregated by end-use (cooling, heating, lighting, plug loads) and cross-referenced with weather patterns and rate tariffs to isolate cost drivers. Simulation software can model “what-if” scenarios, projecting how equipment tweaks or control changes might ripple through the load profile. Benchmarking results against industry norms may identify systems with above-average consumption and help quantify potential savings.
5. Identify Energy Conservation Measures (ECMs)
This step typically develops a prioritized list of energy conservation measures organized by implementation scope:
- Low-cost operational changes
- Moderate-cost retrofits
- Capital-intensive projects
Examples may range from scheduling tweaks and LED relighting to advanced HVAC controls, envelope insulation, or a rooftop solar array. ASHRAE guidelines emphasize tailoring ECMs to building age, climate zone, and budget constraints to ensure recommendations remain implementable.
6. Perform Financial Analysis
Financial analysis of each ECM typically includes calculation of:
- Expected kWh or therm savings
- Utility rate impacts
- Implementation costs
- Payback period
- life cycle return on investment
7. Develop Prioritized Recommendations
This stage typically distills findings into a ranked list that balances ROI, complexity, and strategic goals. Documentation for each measure typically includes scope, cost, projected savings, recommended implementation timeline, and measurement-and-verification steps to confirm results post-installation. This level of detail can be critical for moving projects from paper to procurement.
8. Present Results and Support Implementation
Finally, auditors typically sit down with stakeholders to review the report, answer questions, and refine priorities. Rimkus provides continued support including bid document preparation, contractor oversight, and performance tracking systems to support verification of projected savings in subsequent utility bills.
What are the Benefits of Conducting an Energy Audit?
The financial impact can be significant. Commercial building audits may trim substantial percentages from annual utility costs by uncovering everything from outdated lighting to inefficient HVAC scheduling. Lower operating expenses may feed directly into net operating income, potentially boosting asset value and making the property more attractive to tenants and investors. Utility rebate programs may reduce payback periods.
Environmental benefits may be substantial. Reducing energy consumption typically decreases carbon emissions, supporting progress toward corporate net-zero targets and ESG commitments. Audits quantify both current performance and potential future savings, potentially providing metrics for sustainability reports and green-building certifications.
Regulatory pressures might become easier to navigate. Cities from New York to San Francisco now mandate benchmarking or periodic audits. ASHRAE‐based studies provide documentation that may satisfy compliance requirements.
Beyond the financial and compliance benefits, audits may deliver operational value that compounds over time. Addressing issues such as short-cycling equipment or poor airflow can extend system life, reduce maintenance emergencies, and improve occupant comfort. The resulting action plan can become a roadmap, potentially guiding capital planning and positioning buildings to stay competitive in an efficiency-driven market.
When to Schedule a Commercial Energy Audit
Value can be maximized by auditing at the inflection points that matter. The checklist below helps owners choose the optimal moment.
- Before capital projects or renovations: Planning to replace HVAC, relight, re-roof, or remodel, auditing first may help the findings inform scope, equipment selection, and controls strategy.
- After operational or occupancy changes (within 3–6 months): Shifts in headcount, operating hours, or production loads can create new inefficiencies. A post-change audit may help re-baseline performance and tune schedules, setpoints, and sequences.
- When utility costs or demand spikes without explanation: Sudden bill increases, ratcheting demand charges, or abnormal seasonal swings can signal problems. Scheduling an audit when anomalies appear may help pinpoint malfunctioning equipment, drifted controls, or hidden leaks.
- Ahead of compliance deadlines and certifications (6–12 months prior): Benchmarking, audit ordinances, or goals like ENERGY STAR, LEED, or ISO 50001 typically require lead time. Auditing well before deadlines can preserve room to implement ECMs and document verified results.
- After tariff, incentive, or policy changes: New time-of-use rates, demand response programs, and rebates can reshape project economics. An audit following these shifts may help reprioritize ECMs and capture fresh incentives.
- At key real estate milestones: Lease turnovers, acquisitions/dispositions, and refinancing windows can be ideal moments to quantify savings, de-risk underwriting, and support green-lease clauses or capital plans.
- Seasonally, to capture true operating conditions: For systems with strong weather dependence, planning site work during relevant seasons (e.g., cooling audits in summer, heating in winter) may help observe peak behavior and validate models.
- On a recurring cycle (every 3-5 years): Building performance may degrade over time. Routine audits can help maintain performance, refresh the ECM pipeline, and keep alignment with decarbonization roadmaps and ESG targets.
- For multi-site portfolios: Staggering audits by region and season may help standardize methods, compare EUI and ECM performance across assets, and bundle projects for purchasing leverage.
Rimkus: Engineering Energy Efficiency from Insights to Implementation
Rimkus provides property managers access to MEP engineers, certified energy auditors, and sustainability consultants who collaborate to identify building inefficiencies. Rimkus provides ASHRAE Level 1, 2, and 3 audits. Services extend beyond report delivery to include implementation support.
Drawing on expertise in HVAC systems, building envelope, controls, and renewable energy, Rimkus develops engineered solutions from audit findings, including cost-benefit analysis and rebate identification to support implementation decisions. Rimkus specialists design and manage retrofits. Recommendations are informed by constructability considerations and long-term performance criteria.
For organizations pursuing net-zero targets, Rimkus’ decarbonization specialists model greenhouse gas reductions and develop implementation pathways for electrification and on-site generation, informed by experience in energy resilience and net-zero design. Rimkus provides support from initial assessment through post-implementation verification.
Property managers ready to optimize their portfolio can contact Rimkus to schedule an energy audit or discuss a custom efficiency strategy today.
This article aims to offer insights into the prevailing industry practices. Nonetheless, it should not be construed as legal or professional advice in any form.