Energy Audit vs Energy Assessment: Understanding the Difference
In the ASHRAE framework, a Level I and a Level II study mean very different things. Knowing which one you need — and when — can significantly affect your capital planning and funding eligibility.
The terms “energy assessment” and “energy audit” get used interchangeably all the time — in RFPs, in government program documents, and in everyday conversation with building owners. That looseness creates genuine confusion, especially when you’re trying to determine what a funding program requires, or whether the scope you’ve been quoted will actually support the capital decisions you need to make.
In the ASHRAE framework — the industry standard for building energy studies — there are three defined levels of audit. In practice, what most people call an “energy assessment” aligns with an ASHRAE Level I audit, and what most people mean by an “energy audit” is an ASHRAE Level II. The two studies serve different purposes, involve different levels of effort, and produce very different deliverables.
Here’s what each involves, and how to choose the right scope for your situation.
Energy Assessment (ASHRAE Level I): The Starting Point
An ASHRAE Level I audit — commonly referred to as an energy assessment — is a high-level walkthrough study. It involves a review of utility data, a brief site visit, and a general review of the building’s systems and operations. The output is a preliminary list of energy conservation opportunities, with rough order-of-magnitude estimates of savings potential.
A Level I is most useful as an early screening tool — understanding whether a building has meaningful savings potential before investing in a deeper study, or triaging a portfolio of properties to decide where to focus. It’s a low-cost way to establish a direction, not a destination.
What it isn’t: a study that supports confident capital investment decisions, retrofit tender packages, or most government incentive program applications. The estimates are not detailed enough, and the analysis is not deep enough to carry that weight.
Energy Audit (ASHRAE Level II): The Standard for Capital Planning
An ASHRAE Level II audit is a significantly more thorough exercise, and the standard that most funding programs, procurement processes, and capital planning decisions require. It involves a detailed site inspection of your mechanical, electrical, and building envelope systems; energy modelling; and a prioritised list of Energy Conservation Measures (ECMs), each with detailed cost estimates, projected annual savings, and payback periods.
The output is a document you can act on — one that supports capital budget decisions, retrofit tender packages, grant and incentive applications, and long-term energy planning. At Efficiency Engineering, our Level II audits go beyond standard ASHRAE requirements: we include existing-condition and proposed retrofit schematics, room-by-room lighting inventories, and a full 20-year lifecycle cost analysis for each recommended measure. That means you’re not just seeing the simple payback — you’re seeing the complete financial picture, including energy price escalation, avoided capital costs, and long-term maintenance impacts.
“An assessment tells you where to look. An audit tells you what to do.”
Key Differences at a Glance
If you’re choosing between the two, the practical difference is less about terminology and more about what you need the study to support.
Decision confidence: Level I helps you decide whether to investigate further; Level II helps you decide what to implement.
Financial detail: Level I gives early cost and savings direction; Level II provides the costing and savings analysis needed for budgeting and approvals.
Project readiness: Level I identifies opportunities; Level II turns those opportunities into a scope that can support funding, procurement, and capital planning.
Which One Do You Need?
The right choice depends on where you are in your decision-making process and what you need the output to do.
Choose a Level I assessment if you’re screening a building before committing to a deeper study, triaging a portfolio to prioritise where to focus resources, or need a preliminary read ahead of an ownership or financing decision.
Choose a Level II audit if you’re planning capital upgrades, applying for government funding or utility incentive programs, preparing a retrofit scope for tender, or building a multi-year energy improvement plan.
When in doubt, it’s worth having a conversation with an engineering team before committing to a scope. A brief discussion about your building, your goals, and your timeline is usually enough to clarify which level of study makes sense — and can save you from paying for either more or less than you actually need.
A note on terminology: Program terminology varies. Some government and utility programs use “energy assessment” to describe what is actually an ASHRAE Level II audit — so always confirm the specific requirements before commissioning a study. If a program specifies an ASHRAE Level II audit, that’s a full audit with detailed analysis, not a Level I walkthrough.
The Right Study at the Right Time
Both studies have their place. A Level I assessment can be a smart first step that leads to a more detailed Level II audit. A Level II audit is what moves a project from “we should do something about energy” to “here’s what we’re doing, what it costs, and what it saves.”
At Efficiency Engineering, we perform both studies — and we help building owners determine the right scope before committing to either. If you’re unsure where to start, that conversation costs nothing and help ensure the study is properly matched to your building, goals, and next steps.
Not sure whether you need a Level I or Level II? Get in touch with our team and we’ll help you define the right scope for your building and goals— before you commit.