Date of Publication: July 2, 2026 [2026.08.V-01.C]
Subject: EEDS Forms for Parts of a Building
2024 Ontario Building Code Reference(s):
Part 12 of Division B
Supplementary Bulletin SB-12
Incoming Request:
An application has been submitted for a new building containing one dwelling unit plus a secondary suite. The two dwelling units will have separate heating systems with one using a forced air-gas furnace, and one using an air source heat pump combined with a forced air system. Are separate EEDS forms required or permitted?
Executive Summary:
If distinct parts of a proposed building are designed to meet energy efficiency compliance through different paths (i.e. different prescriptive packages or through different compliance frameworks), more than one EEDS form may be appropriate.
Discussion & Considerations:
There are two types of Energy Efficiency Design Summary (EEDS) forms: the “Prescriptive Method” form, which directs the designer to the prescriptive packages, and the “Performance and other Acceptable Compliance Methods” form. If two parts of a building are being designed using different compliance methods, separate forms would be needed to declare this.
Where the energy efficiency of a building is designed using the prescriptive method, Subsection 3.1.1. (Prescriptive Compliance Path) refers to the energy efficiency of “the building”. This differs in Article 1.1.1.3. (Compliance Options) which refers to “buildings or parts of buildings”. Notwithstanding this, where a design proposes different space heating sources for different portions of a building, this may result in different prescriptive packages. In that case, separate EEDS forms would be required to confirm compliance.
Risk/Benefit Analysis:
Where a designer has chosen to separate parts of a building and achieve energy efficiency using different prescriptive packages or compliance paths, a few points come to mind. The following points are intended to help confirm whether separate EEDS forms are appropriate in a particular application, without changing the underlying compliance requirements.
- It should be confirmed that the portions of the building are distinct and separate parts of the building, and that each part has self-contained, definable mechanical equipment and building envelope elements.
- Where an air source heat pump (ASHP) has an electric back-up, it does not qualify for the allowance found in Sentence 3.1.1.1.(17).
- If the prescriptive compliance method is being used, the options for electric space heating found in table 3.1.1.2.C. and 3.1.1.3.C. heating must be used.
- Not all ASHP’s come equipped with electric back-up, so the exact model and back-up heating source should be confirmed before selecting a prescriptive package.
- Where an ASHP cannot meet the minimum efficiency requirement of Table 3.1.1.2.C. or and 3.1.1.3.C. the performance compliance method may be necessary [Sentence 3.1.1.2.(4).
- The prescriptive compliance method is intended to capture simple energy efficiency scenarios. Where a proposed design does not fit into the prescriptive tables, it may be necessary to choose the performance or other compliance method.
Final Recommendation:
Where different parts of a building are designed to comply with energy efficiency requirements through different compliance paths or prescriptive packages, multiple EEDS forms may be necessary to confirm compliance. Alternatively, energy efficiency compliance may be demonstrated by the “performance or other” compliance method.
Recommendation to Ministry of Municipal Affairs and Housing:
None at this time.
Referenced Documents:
2024 Ontario Building Code O.Reg 163/24 Amended to 05/25
Disclaimer:
This guidance document is intended to assist building officials by gathering relevant information to interpret the OBC Act and the prescriptive requirements of the Ontario Building Code, and is intended to be a best practice aid for building officials.