Asset Classes

Focus Area

Energy and Carbon


Energy and Carbon Assessment

Question #

E1.4 — Deep Retrofit Study


Has a Deep Energy and Carbon Retrofit Study been performed on targeted building systems in the past 10 years?


Applicable to Office, Healthcare, Enclosed Shopping Centre, Universal and Multi-Unit Residential buildings


Select one of the following:

    • Yes – Deep Retrofit Study
    • Yes – Major heating or cooling system retrofit completed in the last five years
    • No


A Deep Retrofit Study is typically focused on a specific system and provides in-depth analysis of carbon reduction options with schematics and specifications for the recommended solution. Align methodology with ASHRAE Level III Audit or equivalent.

Deep carbon retrofits go a step further than a typical detailed energy assessment, providing more in-depth analysis that focuses on a specific system or measure rather than taking a whole-building approach. In deep carbon retrofit studies, detailed assessments are performed on the available electrical capacity for all electrification measures. The study provides detailed cost estimates and a roadmap for implementation. It is the final step required to inform implementation decisions.


In addition to items covered under Question E1.3 Detailed Energy and Carbon Assessment, the Deep Retrofit Study must cover:

    1. Assessment of potential capital projects to reduce energy and carbon with multiple options, such as:
      • Like-for-like replacement as a baseline
      • A deep carbon reduction retrofit as the ‘highest savings’ case
      • An optimized approach that meets multiple prioritized criteria
    2. Assessment of building electrical capacity and required service upgrades for each option
    3. Cost of carbon abatement ($/tCO2e lifetime) of proposed retrofit solution
    4. Detailed life-cycle cost analysis (LCCA) and risk assessment
    5. Identification of potential incentive opportunities


Provide evidence that the building completed a major heating or cooling system retrofit completed in the last five years.


    • Deep Retrofit Study
    • OR Evidence of major heating or cooling system retrofit completed in the last five years

Adapted BB3 Question

New in BOMA BEST 4.0

Suggested Lead





Other Notes

    • A Deep Retrofit Study often includes the development of an energy model, which is a simulation of the retrofit scenarios proposed, to better facilitate effective decision-making
    • The assessment methodology should at least align with an ASHRAE Level III Audit
    • Refer to Energy Star for carbon emission factors. If other carbon emission factors are used, explain the reasoning and factors applied


6 Points