Monday November 10 2025

GHG DISCLOSURE IN MONTREAL: UNDERSTANDING (AND LEVERAGING) THE NEW RATING SYSTEM FOR LARGE BUILDINGS

Montreal has formalized a robust framework for measuring, comparing, and ultimately reducing greenhouse gas (GHG) emissions from its building stock.

Bylaw 21-042 requires annual disclosure of energy data and introduces a GHG performance rating for each building. For owners, managers, and boards of directors, this is not just an administrative requirement: it is a strategic lever that guides investment decisions, communication with occupants, and medium-term asset value. Let’s take a look at what is changing and how to prepare in practical terms.

WHO DOES THE REGULATION APPLY TO, AND WHEN MUST DISCLOSURE BE MADE ?

• Assets covered: All existing large commercial, institutional, and residential buildings ≥ 2,000 m² or ≥ 25 dwellings in the territory of Montreal are subject to the regulation. Certain exceptions exist (e.g., predominant industrial use on the roll, or establishments already subject to specific provincial contaminant reporting obligations).
• Gradual rollout: The regulation was implemented in stages (2022, 2023, 2024) based on surface area/combination of uses, so that since 2024, the general threshold of ≥ 2,000 m² or ≥ 25 dwellings has been fully in effect.
• Annual deadline: Owners must submit monthly energy consumption data for the previous calendar year (January 1 to December 31) by June 30 at the latest. The transmission channel is ENERGY STAR Portfolio Manager (ESPM), and the City provides the transfer profiles to be selected.
• Where to check: Montreal publishes an indicative list of buildings subject to the program (with a building ID that facilitates your procedures in ESPM). The presence or absence of a building on this list does not exempt you from your obligations; it serves as an identification aid and is subject to change.

WHAT THE RATING COVERS: USEFULNESS AND METHODOLOGICAL FRAMEWORK

The rating is a public and intelligible translation of your greenhouse gas (GHG) emissions intensity compared to similar assets. It has three objectives:

• To compare buildings among peers (same use) in order to position your performance in kg CO₂e/m² on a readable scale;
• Guide decisions (CAPEX/OPEX) by showing where action is needed to improve the rating;
• Support market transition (quality data = better targeted programs).

In practical terms, you continue to disclose your data exactly as before (via ESPM). The City calculates the rating based on this information; there is no “second declaration” dedicated to the rating. The tool and guides provided by the City define the scope (the entire building), the granularity (monthly), the required fields (usage, surface areas by usage, meters, etc.), and quality controls (ESPM verifier).

In short: disclosure feeds the rating. The more complete and accurate your data is, the more the rating reflects your operational reality—and the more relevant your “apples-to-apples” comparisons are.

HOW MONTREAL IS ALIGNING ITSELF WITH QUEBEC’S AMBITIONS

The Quebec government’s 2025-2030 Implementation Plan (PEV 2030) includes, in action R3-060, the establishment of a provincial energy disclosure, rating, and performance system for commercial and institutional buildings.

The associated budgets are planned for 2025-2030, confirming the structural focus on transparency and performance in the building stock. Montreal is therefore aligning itself with this provincial trajectory: preparing for municipal ratings means anticipating the expectations of the provincial framework.

WHAT YOU NEED TO DISCLOSE, AND HOW TO AVOID BLIND SPOTS

The quality of the rating depends directly on the quality of the data submitted. The City’s guides and support materials detail the following steps: Guides

• Create/update your properties in ESPM (official address, Montreal building ID, primary and secondary uses, surface areas by use, schedules, and occupancy factors if relevant).
• Connect electricity/gas meters month by month, for the entire year.
• Activate automatic transfers (Hydro-Québec, Énergir) when possible, to limit manual errors and missing data.
• Use the ESPM verifier (Data Checker) to detect inconsistencies, suspicious zeros, and double counts (e.g., common meter vs. tenant meter).
• Submit via the Montreal sharing profiles (“Montreal – Disclosure for the year 20XX – Bylaw 21-042”).

BEST PRACTICES FOR DATA QUALITY (QUICK CHECKLIST):

• Floor space: clearly distinguish square footage by use (e.g., commercial ground floor + residential floors), and update after any redevelopment;
• Meters: avoid mixing buildings in the same meter; if a meter covers several buildings, document and break down correctly;
• Complete period: make sure you have 12 consecutive months (Jan.→Dec.) without any “data gaps”;
• Changes in occupants: in the event of vacancies or schedule changes, update the usage intensity (occupancy) fields in ESPM.
• On-site fuels: include all energy sources (e.g., backup fuel oil, propane) and their emission factors in accordance with City/ESPM instructions.

THE RATING, IN CONCRETE TERMS: INTERPRETATION, COMPARABILITY, AND DECISION-MAKING USE

Interpretation of “GHG intensity.” The central logic of the rating is based on emissions intensity relative to surface area (kg CO₂e/m²). This metric neutralizes size and allows for comparison between similar buildings (use, configuration), rather than judging gross consumption. In the Montreal context, municipal data aggregation (entire building stock) makes it possible to identify credible local benchmarks.

Comparability “between peers.” No two buildings are ever identical, but the municipal method aims to bring comparables closer together: we avoid comparing a hospital to a residential building, or a large 24/7 shopping center to a 9-to-5 office building. The quality of your metadata (uses, schedules) is therefore a determining factor in the relevance of the rating.

DECISION-MAKING USE

The rating becomes a tool for dialogue with:

• Your board of directors and your co-owners/tenants: it explains “where we stand” and “what trajectory to aim for”;
• Your professionals (engineers, energy managers): it prioritizes measures (heat recovery, HVAC adjustments, destratification, variable speed drives, network insulation, conversion of fossil fuel uses, etc.) according to their GHG impact per square meter;
• Your lenders: it supports an investment thesis (reduction of regulatory and operational risks, improvement of net income).

“Not just a rating”: open data, programs, and trajectories

The City publishes its open data on the consumption and GHG emissions of municipal buildings (≥ 2,000 m²), illustrating the aggregation and transparency approach that the rating will generalize to the private sector. The benefit for owners: anticipate the data ecosystem (comparisons, benchmarks, third-party tools) that will emerge around public ratings.

On the policy side, Montreal’s Climate Plan points out that buildings account for ~28% of local emissions, which justifies dedicated actions and the rise of disclosure/rating mechanisms. For a property owner, this means that incentives (technical, financial, regulatory) will continue to evolve in this direction: a ready and costed pipeline of projects becomes a competitive advantage.

Finally, at the Quebec level, Action R3-060 of the PEV 2030 (2025-2030) includes disclosure + rating + performance in a future harmonized provincial framework for the commercial and institutional sector: prepare for methodological convergence and increasingly clear signals on minimum expected performance.

10-STEP ACTION PLAN (READY TO USE)

Step 1 — Check eligibility. Confirm that your assets (≥ 2,000 m² or ≥ 25 dwellings) are eligible and locate the building ID in the municipal list. If you manage a multi-building portfolio, consolidate an internal register (municipal ID, ESPM ID, address, use, m², meters).

Step 2 — Map uses. In ESPM, break down the m² by use (e.g., ground floor shops, offices on floors 1-3, residential on floors 4-15). This granularity is key to comparability.

Step 3 — Close the meters. Collect all monthly bills and connect them (electricity, gas, other fuels). Enable automatic transfers (Hydro-Québec, Énergir) when available to secure the data chain.

Step 4 — Quality control. Before June 30, run the ESPM checker:

• identify data gaps;
• correct units and duplicates;
• document events (major construction, exceptional vacancies, schedule changes) that explain variations.

Step 5 — Share with Montreal. Use the “Montreal — Disclosure Year 20XX” sharing profiles provided by the City to officially transfer your data. Keep internal proof (screenshots, ESPM reports)

Step 6 — Read your GHG intensity. Once your data has stabilized, track your kg CO₂e/m² in ESPM; compare it to your sister assets (same uses). Set an internal target (e.g., -15% over 24 months).

Step 7 — Build a portfolio of measures. Classify them into three categories:

• Zero-CAPEX operations: HVAC time settings, setpoint optimization, sequences (night savings), balancing;
• Targeted efficiency: variable speed drives, heat recovery, network insulation, airtightness, automation upgrades;
• Decarbonization: conversion of fossil fuel equipment, electrification, hybrid solutions, end-of-life planning.

Prioritize according to GHG impact/m² vs. cost vs. complexity. (This step works very well with your own data and city guides.)

Step 8 — Investment roadmap. Place measures over 12-36 months: quick wins (3-9 months), medium-term projects (12-18 months), structural projects (18-36 months). Integrate risk management (reduction of breakdowns, operational stability, comfort).

Step 9 — Governance & communication.

• Board of directors/co-owners/tenants: explain the rating and your trajectory (before/after measures);
• Suppliers/engineers: align specifications with GHG/m² targets and not just kWh;
• Financing: prepare a business case (CAPEX, savings, GHG avoided, risks avoided).

Step 10 — Annual cycle. Repeat: quality control → submission before June 30 → update the plan according to the new rating/results. This discipline puts you one step ahead of upcoming provincial signals (R3-060).

“SO, WHAT DO WE DO NOW?” OUR 2025-2026 PLAN

• Operations (0-9 months): recalibration of HVAC schedules, set points, insulation;
• Efficiency (9-18 months): heat recovery on AHUs, variable speed drives, optimization of PLCs;
• Decarbonization (18-36 months): conversion of fossil fuel heating, hybrid solutions;
• Target: -15% GHG/sq. ft. in 24 months, with quarterly monitoring and submission by June 30.

Why now?

• The rating will show our progress transparently;
• The provincial framework (R3-060) confirms the direction: getting equipped early reduces risk and cost.