Measure Overview
Title 24 Part 6 sets requirements for pool heating systems. The current requirements are triggered when a new pool is built with a heating system or when an existing pool adds a heating system for the first time. The code currently requires the use of one of the following compliance options:
- solar thermal systems for pool and spa heating (excluding portable electric spas)
- heat pump pool heaters (HPPH) meeting specified coefficient of performance (COP), sizing, and controls criteria
- on-site renewable energy or site-recovered energy systems
- a combination of a solar pool heating system and heat pump pool heater without any additional supplementary heater
- or a pool heating system determined by the California Energy Commission (CEC) Executive Director to use no more energy than the previous system.
The proposed code change would expand the scope of the swimming pool and spa heating requirements to include existing nonresidential pools that are replacing an existing pool heating system. Single-family residential pools, multifamily pools, and hotel/motel pools with an existing pool heater, however, would remain exempt from these requirements and may replace their heating system with the same technology.
The proposal would also introduce a new compliance pathway: a condensing gas pool heater with a minimum efficiency of 94%. In addition, the solar sizing requirements for nonresidential existing pool heaters would be reduced to 40% of the pool surface area, compared to the 65% sizing requirement for nonresidential new construction.
The proposal would add an exception for permanent spas that lack adequate solar access roof area (SARA).
Provide Feedback
This measure page will be updated as the 2028 code cycle progresses. For questions or suggestions, email [email protected]. Please include the measure name in the subject line.
Scope of Proposed Code Change
| Building Type(s) | Construction Type(s) | Type of Change | Updates to Compliance Software | Third Party Verification |
| Nonresidential | Additions, alterations | Mandatory | No updates | No changes to third party verification |
Justification for Proposed Change
California is home to one of the largest pool markets in the nation, and pool heating represents a major energy use—especially in nonresidential and multifamily settings where pools are often heated year-round. Expanding heating source system requirements to include alterations where the pool heater must be replaced at existing commercial pools would save pool owners significant costs and support California’s long-term decarbonization goals.
The existing code provides flexibility through compliance pathways that include solar thermal systems, heat pump pool heaters, and on-site renewable energy or energy recovery. Solar thermal systems are commercially available and reliable technology. The installation of solar thermal collectors in existing buildings with pools or spas can become the primary source of heating while enabling existing heating systems to serve as a supplementary heating source.
The proposed change would further expand compliance flexibility by adding condensing gas heating as a new pathway. Condensing gas pool heaters are high‑efficiency systems that capture heat normally lost in the exhaust of a non‑condensing gas pool heaters. By cooling the exhaust gases enough to condense the water vapor back into liquid, these systems recover additional heat and use it to warm the pool water. This process is what makes condensing heaters significantly more efficient—often exceeding 90% efficiency—compared to the typical 82 or 84%-efficient non‑condensing gas heater. This option is particularly beneficial for pool owners with limited roof space for solar thermal installation.
The proposed measure would build on the foundational work from the 2025 code cycle and would take a strategic step toward transforming the market.
Relevant Documents
Round One Utility-Sponsored Stakeholder Meeting Materials
-
Use the form above to provide feedback on this measure.
Give Us Your Feedback
The Statewide CASE Team values input from all stakeholders engaged in the Title 24, Part 6 code change process. We encourage the open exchange of code change comments and concerns.