When Darrel McMaster first started installing electric vehicle charging capabilities in his homes’ garages in the mid-2000s, it was usually just a periphery add-on for his buyers.

“At that time, our homeowners were asking for them, but the electric car was still kind of just the third car in the family,” says McMaster, owner of Boerne, Texas–based Sustainable Homes, which builds both net-zero energy and net-zero water homes. “There weren’t a lot of real choices of vehicles, and so they weren’t getting rid of their gas cars.”

Today, when McMaster builds a new, high-performance home, the paradigm has shifted. “We just finished a home where we installed a dual charging system that will charge two EVs at the same time. Now, the gas car is No. 3. The EVs are Nos. 1 and 2.”

What a difference 15 years and a national push to electrify the vehicles on America’s roads make.

While Pew Research Center cites 1.8 million EVs registered in the U.S. today, representing just 2% of new car sales, EV sales could be as high as 32% of total light vehicle sales in the U.S. by 2030 and 45% by 2035, according to London-based data research firm IHS Markit.

That growth will be spurred, in part, by President Joe Biden’s focus on going electric. Over the summer, Ford, General Motors, and Stellantis (formerly Fiat Chrysler), which make up 44% of the U.S. market, coordinated with the White House to announce a goal for EVs to represent 40% to 50% of the Big Three’s total sales by 2030. And there are already 40 EV models available for purchase in the U.S. today among all manufacturers, according to EV owners group Plug In America.

The focus on EVs by both manufacturers and consumers also is being driven by a build-out of public EV charging infrastructure. While there are only about 41,400 EV charging stations in the U.S. today—compared with more than 136,000 gas stations—the $1 trillion infrastructure bill Biden signed into law in November includes $7.5 billion to roll out more, which should go a long way toward the president’s pledge to build 500,000 public EV chargers by 2030.

But while the focus at the national level has been on manufacturing goals and public EV infrastructure, the places where the coming multitudes of EVs will spend the majority of their time—the garages of single-family homes—haven’t received as much attention. It’s emerging as a major blind spot for policymakers, EV owners, and home builders alike.

“Right now, the largest electrical demand in the house is the HVAC system,” McMaster says. “But soon, it’s going to be the car, and it’s going to exceed everything else. We’re already in a situation where our power grid is struggling to keep up. What’s going to happen if we add millions of these cars to an electrical grid that’s just not prepared to take the load?”

The answer to that question is at once both simple and complex. Like the home building industry itself, it’s also fragmented. And how it will ultimately be addressed by the industry is as varied as the home builders who make up its ranks.

What Home Builders Are Doing Now

For many home builders who are already wiring their homes to be EV ready, the question hasn’t even really come up—yet. Take Vancouver, Washington–based Evergreen Homes NW, which offers its customers the option of prewiring their homes to be EV ready, an increasing request from its customers.

“Even if they don’t have an EV today, everybody sees where this is headed,” says Becky Sundstrom, the family-owned home builder’s marketing director. “So more of our buyers are interested in at least being car charger ready.”

For most people, that means installing at least an extra 30-amp circuit in the garage (Tesla owners require 50 amps) that widely available after-market car chargers from the likes of Webasto, ClipperCreek, and Leviton can plug into.

The same electrical subcontractors who already wire your homes can do the job, usually on a standard 200-amp panel. Depending on what circuit is used, costs range from between $250 and $500 per home. That’s a bargain, compared with the $1,000 to $3,500 price tag of retrofitting for a charger down the road.

“It’s exactly the same as a dryer plug,” Sundstrom says. “It’s pretty simple.”

At Bridgehampton, New York–based high-end custom home builder P3 Builder Group, owner John Barrow says he’s evolved his approach to prewiring his homes to be EV ready over the last four to five years.

“People used to ask for it, but it wasn’t a hot item,” Barrow says. “Now, when my electrician asks me if they’re putting in a charger so he can figure out the loads, I just tell him to figure that they are.”

And at Addison Homes in South Carolina, which builds to the Department of Energy’s Zero Energy Ready Home standard, president Todd Usher has started to offer an EV-ready option to all his home buyers with a 50-amp circuit. Like McMaster, he recently had a client who wanted to be prewired for two vehicles.

“That’s a very simple choice to offer someone in a home that ultimately saves them thousands of dollars later, if they decide to become more environmentally conscious,” Usher says. “As an industry, we need to lead and be the experts to our homeowners to say, ‘Here are your choices, and this is why it might matter to you.’”

Happening with the Nationals, Too

It’s not just smaller custom home builders who are wiring their homes to be EV ready for clients, either. For example, Los Angeles-based Top 10 builder KB Home has been offering EV charging as an option to buyers since 2010.

At Incline Village, Nevada–based Tri Pointe Homes, the firm’s Seattle division started offering a prewired circuit that’s ready for an EV charger in the garages of its homes as standard in the past few years. It’s already wired approximately 500 of its homes to be EV ready in that region, and it doesn’t plan to stop there.

“We’re a national builder that’s heavily concentrated in the West, and we see demand increasing west to east,” says Kevin Wilson, national vice president of strategic sourcing and sustainability. “We’re looking at this holistically and don’t want to start breaking the strategy apart by approaching it regionally. We’re going to make it global across Tri Pointe because it’s a cost benefit to the homeowner, and the cost is minimal.”

No Coordination Across the Industry

Despite those efforts at both custom and production builders, industry pros say there hasn’t been a coordinated push within home building to make sure the topic is on builders’ radars or that they get it right when it comes to meeting what many say will be overwhelming demand.

“Builders are all over the map when it comes to EV-ready homes,” says Ted Clifton, president of Coupeville, Washington–based Zero-Energy Home Plans. “A lot of them are totally on board with it. But others are only coming along kicking and screaming.”

For example, in a recent survey of home builder division presidents conducted by Zonda, BUILDER’s parent company, 12 of 22 respondents said they were currently offering an EV option for their customers. But 10 said they were not, even though nine of them indicated they were exploring the idea.

But the one outlier was a Top 10 builder who replied that while they maintain a focus on energy efficiency, they aren’t offering an EV-ready option yet because customers have not been asking for it.

“We see limited demand in our submarkets for EVs,” the division president wrote.

Buyers Know Best

That feedback from builders on the front line, however, runs contrary to other data collected by Zonda on home buyer preferences. For example, in a 2020 survey of nearly 25,000 home buyers, the company found that 49% said they’d be willing to pay $1,000 to have their new home prewired for an EV charger. That choice was up 12% from the previous year.

“It’s growing quickly,” says Mollie Carmichael, principal at Zonda Advisory. “Most home builders are at least talking about prewiring. The real question is how many are making something like that standard? It’s really not expensive to do it upfront.”

The fact that some home builders are waiting to see demand before committing to going the EV route shouldn’t be surprising. There was a similar lag just a few years ago with smart home technology, before it became a standard industry offering, seemingly overnight. Given the relatively straightforward process of stringing wiring for a 30-, 40-, or 50-amp circuit, a similarly quick pivot could happen with EV-ready homes.

Builders who have already gone the EV-ready route also argue that waiting until customers say they want EV-ready homes may be too late, and at the very least turns a blind eye toward what’s happening in the broader drive toward EVs in the U.S.

“As builders, it’s our responsibility to ask those questions about EVs, because the homeowners don’t necessarily know what might be important five years from now,” says Evergreen’s Sundstrom. “But we know because we’re thinking about it. It’s really our job to ask those questions and find out what kind of a commute you are going to be making.”

No Code for EV Wiring

The home building industry also hasn’t shown a uniform embrace of EV-ready homes where codes are concerned.

For example, back in 2019, the original proposal for the 2021 International Energy Conservation Code included electrification portions that would have required new homes to have wiring for EV chargers. But those provisions weren’t ultimately included in the IECC that was approved, at least partially at the behest of the National Association of Home Builders.

“Yes, NAHB objected to the EV provisions, but it was more on procedural grounds than substance,” says Susan Asmus, NAHB’s senior vice president of regulatory affairs. “We were concerned that the proposal to wire for EV outlets had nothing to do with the effective use and conservation of energy, and that it would fit better in a different part of the International Residential Code or in the National Electric Code.”

While some municipalities such as Atlanta, Denver, and Seattle, as well as California, already have residential EV wiring requirements for new homes on the books, the failure to have EV-ready homes included in the 2021 IECC has been bemoaned by advocates as a missed opportunity.

“It was disappointing,” says Joel Levin, executive director of Plug In America. “The EVs are coming. If you’re building a house and you’re not planning for the needs of the person living there five or 10 years from now, you’re doing your customers a huge disservice.”

A Question of Grid Capacity

For others, building out America’s EV charging infrastructure one home at a time goes beyond the will to do it, however. It also comes down to the very real constraints doing so could put on the nation’s electrical grid, the same concern McMaster voiced in Texas.

For C.R. Herro, former vice president at Meritage Homes who recently joined Tampa, Florida–based Bettr Homes as its executive vice president of operations to build net-zero, electric, sustainable communities in the Southeast while still consulting for his former employer, truly answering the EV-ready call means getting all the stakeholders who matter at the same table.

The reason why, he says, is because there’s a difference between custom home builders, or even a divisional arm of a larger builder, putting up a dozen EV-ready homes at a time, and multiple, national production builders throwing the switch, all at once, on their EV ambitions.

“We’re not seeing a huge adoption of EV-ready homes, not because of the expense of doing it, but because of the lack of grid availability,” Herro says. “Building a one-off is one thing. But when you tell a utility modeler that you’re going to add 50 amps per house across 50 lots, they’re going to tell you they don’t have it in the drop.”

EV advocates such as Levin point to the fact that most EV home charging will be done during off-peak hours, at night, when overall grid demands aren’t that high. But even though many utilities around the country have already adopted time-of-use rates to encourage people to use electricity at off-peak hours, many of their modeling processes still look at that additional 50 amps as being additive, or “stacked” on top of the entire existing load a non-EV-ready home already has.

“Because there isn’t a history for the way people use EVs yet, the utilities are going to assume the worst-case scenario, and that it stacks on top of historic loads,” Herro says.

That could result in utilities requiring builders to upgrade the underlying electrical panels in their homes to meet the theoretical maximum draw the home could put on the grid. That would mean a standard 200-amp panel would need to be upgraded to the next size up—400 amps.

“Just running a 50-amp circuit with a 220-volt plug in the garage is not a big deal, it’s a few hundred dollars,” Herro says. “But it is a significant cost to jump up the service capacity from the baseline to account for all those cumulative amps. More importantly, the utility might not have that capacity in the transformer. So now you’re talking about dropping new transformers and pulling the main miles into that house to do it. Then you’re talking about real capital.”

In order to overcome that challenge, Herro says charging technology needs to ensure cars only charge during off-peak times, and utilities need to be confident that EV chargers won’t overload the grid so home builders can give their customers the EV charging capabilities they’re increasingly asking for—but none of that has happened yet.

“The utility companies, the builders, and the EV chargers have to get on the same page, but there’s not a clear leader,” Herro says. “So we’re all kind of shuffling around, trying to get everybody else to see it the same way.”

NAHB’s Asmus agrees.

“We know that electric vehicles will play an increasing role in providing for the nation’s transportation needs in the future and all stakeholders will have to work together to find cost-effective and workable solutions to ensure the necessary infrastructure is in place to support EV use,” Asmus says.

And yet still, the EVs are coming.