How ASHRAE Energy Audits Work: A Guide for Ontario Building Owners

What Is an ASHRAE Energy Audit?

An ASHRAE energy audit is a structured assessment of a building's energy performance, built around standards published by the American Society of Heating, Refrigerating and Air-Conditioning Engineers. For building owners in Toronto and across Ontario, it's the standard reference point utilities, incentive programs, and engineers use when they talk about "getting an energy audit" — not a marketing term, but a defined methodology with three distinct levels of depth.

The goal is straightforward: understand exactly where a building is losing energy and money, and quantify what it would take to fix it. That output becomes the foundation for every retrofit decision that follows, from a single boiler replacement to a full building automation overhaul.

Level 1, 2, and 3: Which Does Your Building Need?

A Level 1 audit is a walk-through assessment — a relatively fast, low-cost review of utility bills and a visual inspection of major systems. It's useful for benchmarking a building or deciding whether a deeper look is warranted.

A Level 2 audit goes further: a detailed energy survey with equipment-level analysis, load calculations, and a prioritized list of energy conservation measures (ECMs) with estimated costs and payback periods. Most commercial and multi-residential retrofit projects in the GTA start here — it's detailed enough to support real capital planning decisions.

A Level 3 audit is reserved for capital-intensive projects. It includes detailed engineering analysis, often building energy modelling, and investment-grade accuracy on savings projections — the level of rigour lenders and incentive programs expect for larger retrofit financing.

What Happens During the Audit

An engineer reviews 12–24 months of utility data to establish a baseline, then conducts a site visit to inspect mechanical systems (boilers, chillers, air handling units), the building envelope, lighting, and controls. For a Level 2 or 3 audit, this includes spot metering, equipment nameplate data collection, and interviews with building operations staff about how systems actually run day to day — which is often different from how they were designed to run.

What You Get at the End

The deliverable is a report ranking energy conservation measures by payback period, from no-cost operational changes to capital projects like boiler retrofits or BAS controls upgrades. Crucially, a properly documented ASHRAE audit is also what most Ontario incentive programs require before they'll approve funding — skipping this step, or using an informal assessment instead, can disqualify a building from incentives worth tens of thousands of dollars.

Why It's Worth Doing Now in the GTA

Ontario's building stock skews older, and utility rates have only trended upward. An ASHRAE audit is the single highest-leverage first step for any building owner weighing a retrofit — it turns a vague sense that "the energy bills are too high" into a prioritized, financially justified action plan.

Mann Engineering has conducted ASHRAE audits across commercial, institutional, and multi-residential buildings throughout Toronto and the GTA for over 40 years. If you're not sure whether your building needs a Level 1 or Level 2 audit, that's a five-minute conversation — reach out and we'll point you in the right direction.