Building Code Committee approves updated rules for heat pump capacity and exceptions

The SBCC WSEC-C TAG meeting held on April 4, 2025, focused on critical updates to building energy codes, particularly regarding heating systems and their efficiency standards. The discussions centered around clarifying exemptions and requirements for heating capacities, with a significant emphasis on the integration of heat pumps and the treatment of various heating appliances.

One of the primary topics was the approval of updated language concerning the 5% exception for low heating capacity dwellings. Participants discussed the need for clarity on which heating systems contribute to this exception, including heat pumps and auxiliary heating sources. The motion to approve the revised language was passed unanimously, indicating strong support for the proposed changes.

Further discussions highlighted concerns about the implications of these changes on smaller heating units, such as electric resistance heaters used in specific scenarios like stairwell freeze protection. Members sought assurance that these units would still be viable under the new regulations, emphasizing the importance of not closing off options for smaller spaces.

Another significant proposal involved the clarification of the primary and supplemental heating capacities required by the code. The committee discussed the need to ensure that at least 50% of the primary heating capacity must be provided by heat pumps, with the remaining capacity open to various equipment types. This change aims to streamline compliance and enhance the overall efficiency of heating systems in buildings.

Additionally, the meeting addressed the exclusion of hybrid heat pump water heaters from certain exceptions, based on the MVPE committee's determination that these units do not meet the intended efficiency standards. This decision sparked debate about the potential impact on residential buildings, particularly those that may rely on these units for compliance under the current code.

The committee also considered the inclusion of fossil fuel heating options, particularly in commercial settings, where high-efficiency gas water heaters could provide a viable alternative to electric heat pumps. This discussion underscored the ongoing tension between promoting electric heating solutions and accommodating existing efficient fossil fuel technologies.

In conclusion, the meeting underscored the committee's commitment to refining building energy codes to enhance efficiency while addressing practical concerns from various stakeholders. The approved proposals will be integrated into future code drafts, with further discussions anticipated on the inclusion of additional heating technologies. The next steps involve reviewing the implications of these changes and ensuring that they align with broader energy efficiency goals.