Denver’s new building codes include a change aimed at making it easier — and cheaper — for more residents of the fast-growing city to charge electric vehicles at home.

Although opposed by homebuilders, the electric vehicle readiness requirement says new single-family homes and duplexes built in the city will need to have the right electrical wiring to support electric vehicle plugs in their garages. At the least, the new homes must have conduits leading to the electrical panel.

While owners of older homes often must dig or break through walls, that latter option would allow a resident to install the wiring needed for a charging plug easily.

“It’s very basic electrical work,” said Mike Salisbury, a senior transportation associate with the Southwest Energy Efficiency Project, which advocated for the requirement. “What this tries to do is make sure it’s easy and inexpensive for a new homeowner (to install) a new charging station.”

The electric vehicle change was part of a large-scale update of the city’s building and fire codes that won approval Monday from the City Council.

Other building- and fire-code changes are meant to ease rules and costs to make it easier for property owners to renovate older buildings rather than raze them, says the Denver Department of Community Planning and Development.

Overall, new buildings constructed under the code revisions will be safer, the city says, and up to 25 percent more energy-efficient.

The Denver planning department’s proposed changes were spurred by the 2015 update to the International Code Council’s suggested rules, which serve as a sort of industry standard, along with Denver-specific amendments.

Those include the new requirement for electric vehicle-supporting conduits and panels in garages for new houses.

Initially, that change faced opposition, especially from homebuilders concerned about the added cost in construction.

But Salisbury says it would add a negligible amount for some new homes, while costing $200 to $300 for others, depending on whether the garage is attached and how far it is from the electrical hookup.

“It’s pretty minimal compared to the price of a new home,” he said.

Ultimately, a building-code committee that included representatives from the design and construction industries approved the change unanimously, Salisbury said. Homebuilding groups still opposed the change, he said.

Denver is joining several places that have electric vehicle readiness rules for single-family homes, including Boulder County; Vancouver, British Columbia; Los Angeles; and several other California cities. Some of those, as well as Salt Lake City, have requirements covering multifamily residential developments, according to Denver’s amendment proposal.

Another instance of the city customizing the building-code changes is a new requirement that garages and accessory buildings be included on the primary residence’s electric meter.

The intent of that, the city says, is to aid firefighter safety and to make it less likely that an off-site party would be able to rent those buildings on residentially zoned property for illegal marijuana cultivation.

Councilwoman Robin Kniech said the updates would help Denver catch up to other cities on sustainability-focused building codes that were part of a previous international code update skipped by the city.

The council approved the building code changes 12-0.

“Embracing best practices in safety, quality and sustainability is a long-term commitment to our city and its future,” CPD executive director Brad Buchanan said of the updates in a news release. “Through an open and collaborative review process, design and construction professionals, property owners and code officials reached consensus on standards that will serve us well for years to come.”

The new building code takes full effect in six months. Until then, contractors and residents seeking building permits will be able to choose whether city reviewers will rely on the city’s 2011 code or the new one in evaluating their applications.

Jon Murray: 303-954-1405, jmurray@denverpost.com or @JonMurray