On Tuesday the city council will be looking at amending the energy efficiency code to require that mixed-fuel single-family dwellings and low-rise multi-family residential projects to achieve a total Energy Design Rating (EDR) margin of 9.5 for SFD and 10 for low-rise multi-family, per the cost effectiveness study prepared by Frontier Energy and Misti Bruceri & Associates.
It would also require pre-wiring for a future retrofit to all-electric appliances in mixed-fuel new single-family dwellings and low-rise multi-family buildings.
The city has a long history of energy efficiency and sustainability requirements going back to the 1970s, and most recently in 2008 with the first green building ordinance in the region and the most comprehensive in the state.
The city continues with a new proposal that will incentivize all-electric in single-family dwelling as well as low rise multi-family buildings.
City staff notes, “The proposed Ordinance will be consistent with all of the reach codes adopted over the last 12 years by requiring a cost effective compliance margin.
“Full CALGreen, Tier I compliance regarding energy efficiency has not been found to be cost effective, therefore the proposed Ordinance will require a total Energy Design Rating (EDR) margin of 9.5 for SFD and 10 for low-rise multifamily consistent with the cost effectiveness study”
The California Energy Commission has approved the 2019 California Energy Code, going into effect on January 1, 2020. This code requires single-family and multifamily low-rise buildings to “offset 100% of the electricity used on site, excluding some specific electrical loads.”
The purpose of this is “to take the additional step of providing a path to reduce the use of fossil fuels in residential buildings.”
Staff notes that since 2008 the City “has enacted an energy efficiency reach code that requires projects to go beyond the requirements of both the California Energy Code and the California Green Building Standards Code (CAL Green) to a point that is cost effective.”
The only difference with this proposed Ordinance is that all-electric homes will not be required to go beyond the minimum code requirements.
City staff views this requirement as responsive to the resolution that declared a climate emergency and called on the city to take steps to restore a safe climate that includes “an acceleration of the carbon neutrality goal for the Davis community from 2050 to 2040.”
The staff report notes that staff has analyzed the potential for requirements that all new residential buildings go all-electric – as some of the recent developments have done voluntarily.
However, they worry that there is the potential for residences from the building community which “could possibly result in litigation as it is not found to be cost-effective at this time.” Thus staff views this as an alternative, where they “incentivize” rather than “require” all-electric buildings.
They write: “As an incentive for all-electric homes, the proposed Ordinance would not include additional energy efficiency requirements beyond code compliance for homes that do not utilize fossil fuels. To facilitate future retrofits for mixed-fuel homes, the proposed Ordinance will require pre-wiring for electric appliances.”
The city has for the most part “relied upon negotiated Development Agreements with larger developments to achieve voluntary agreement to comply with energy efficiency and PV provisions that may not otherwise be enforceable, absent a Development Agreement.”
They add, “A cost effectiveness study allows the City is to adopt local ‘reach codes’ exceeding the standard State energy efficiency requirements, eliminating the need to negotiate such requirements on a project-by-project basis, and providing for consistency amongst projects.”
Staff writes: “Single-family dwellings that are constructed as mixed-fuel dwellings that meet a total EDR margin of 9.5 will cost approximately $5045 more than the Standard Design code compliant house.
“The percentage of savings will be approximately 17% and the emissions savings will be approximately .35 lbs.-CO2/sf/year. A 2000 sq. ft. home will save 700 lbs. of CO2 per year.”
Staff projects that “In new developments, single-family dwellings that are constructed as all-electric homes will see an approximate savings in natural gas infrastructure cost of $5349 per home as gas infrastructure could be eliminated as part of the overall development.
In addition, “For new single-family homes built on an infill lot where gas infrastructure has already been installed, the upfront cost savings would be less. The home would save the costs of the gas piping in the home and the elimination of the service run from the street but would not have the benefit of cost-savings for elimination of the utility installed beneath the roadways.”
—David M. Greenwald reporting