Revised Municipal Code of the City and County of Denver Colorado, Sec. 10-20. - Electrification requirements for existing buildings

Residential Multifamily and Commercial Buildings

Heat pump requirement text: 

(2)When a unitary air conditioner or condensing unit is proposed to be replaced, the unit shall include electric equipment capable of providing space heating, and any other heating equipment serving the space shall be reconfigured to provide only supplementary heat.
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(4)The electrification requirements of subsections (c)(1)—(3) above may be met by a heat pump or by electric resistance space or water heating equipment. If the electrification requirements are met by electric resistance space or water heating equipment, then the system shall be provided with an onsite renewable energy system sized to provide not less than one hundred (100) percent of the annual energy use of the electric resistance space or water heating equipment, with the following exceptions: an onsite renewable energy system is not required where heat pumps are not available for that system type, or where new electric resistance equipment is replacing existing electric resistance equipment. An onsite renewable energy system used to comply with this section shall not be used to meet any other regulatory requirement.
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(8)Exemptions for emergency replacement and economic hardship shall be provided. An economic hardship exemption will not be available for a system that can be replaced with an electric heat pump at near cost parity, which will be defined as the cost of a replacement of a natural gas space or water heating system to a partially electric heat pump system, including all incentives, that is within five (5)—fifteen (15) percent of a like-for-like natural gas space or water heating system replacement, including the social cost of carbon dioxide of the like-for-like gas system replacement over its lifetime. 

When an electrically operated PTAC [portable terminal air conditioner] or single-package VTAC [vertical terminal air conditioner] that serves a heated space is proposed to be replaced, the air conditioner shall be replaced with electric equipment that provides both heating and cooling. Any other space heating equipment shall be configured to operate as supplementary heat.

Additional requirements

Starting March 1, 2023:
When a unitary air conditioner or condensing unit is proposed to be replaced with another unitary air conditioner or condensing unit, then only one (1) of the following is required:i.Submitting an electrification retrofit feasibility report.ii.Sizing the equipment based on the current space conditioning needs of the building with Denver Building and Fire Code requirements, and an analysis prepared by a registered design professional of the existing building's envelope, ventilation requirements, and load calculations based on ASHRAE/ACCA 183 or approved equivalent.iii.Pressure testing of all natural gas piping.

Starting January 1, 2027:
An electrification retrofit feasibility report looking at the feasibility of installing an electric packaged terminal heat pump (PTHP) or single-package vertical heat pump (VTHP) space system that provides both heating and cooling shall be submitted when an electrically operated packaged terminal air conditioner (PTAC) or single-package vertical air conditioner (VTAC) that serves a heated space is proposed to be replaced.