Shouldn’t All New Homes be Pre-Wired for Electric Vehicle Chargers?


About 4 weeks ago, we reported on a story that the city council of Palo Alto, California voted unanimously to required that new homes come pre-wired for plug-in vehicle charging stations; that news went viral.

Jay's Now Infamous "Green" Home - The One That's Definitely Not Built to Last

Jay’s Now Infamous “Green” Home – The One That’s Definitely Not Built to Last. (Apologies on the inside joke; as the house has a lot of ‘flaws’)

By viral, we mean that if you didn’t come across a similar article elsewhere after our initial posting, then you probably haven’t been on the Internet since then.

With the widespread mania surrounding Palo Alto’s decision, we thought it would be worthwhile to place the city’s decision in greater context.

Why stop at Palo Alto?

We’ve already seen countless builder commit to pre-wiring all of their future builds for EV chargers, but why not make this a mandate?

Yes, most building codes are state-by-state, meaning that the federal government can’t really step in to mandate changes to state-level or even regional building codes, but why not convince all states to mandate/enforce this change?

It’s a simple change and it’s cheap.

It’ll cost builders maybe $100 to $300 to make new homes EV-ready and that cost can be passed on to homebuyers.

Nobody loses.  Everybody wins.

At least that’s how we see it.  What do you think?

Categories: Charging


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22 Comments on "Shouldn’t All New Homes be Pre-Wired for Electric Vehicle Chargers?"

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I’ve already encountered some people around in Texas here who are pissed off at the thought of pre-wiring a home for EVs. They don’t want the added cost to the home and don’t like Government forcing anything upon them.

Personally, I think it is a good idea because it will actually save a lot of money in the long-run because we all know at some point in time most homeowners will probably be driving some sort of plug-in car. We also know the cost of adding a charger after the fact is much higher.

As a fellow Texan, maybe we should “spin” it as an “auxiliary plug” where people can plug in their deep freezer for the deer they just harvested. Wire up a NEMA 14-50 and let people use it as they see fit.

What, Texans don’t want a BIGGER, MOAR POWERful 240V socket in their garages? They’d rather just have those dainty little 120V every day sockets? Come on, Texas.


We don’t know what the market’s going to do, or whether it’ll even be around, apart from high-end luxury, so we don’t know what wiring and supply is needed.

Just spec sufficient conduit space for additional 50A cabling per parking space.

If the Circuit breaker box is in the garage, the cost is minimal. Doesn’t mean it has to have an EVSE installed – just a 240V line of 30A pulled from the main service panel. About $200.

Dr. Kenneth Noisewater

Making it available as a packaged upgrade makes sense, forcing it on folks who don’t want it doesn’t. However, many garages are going to have 240V for dryers or “man cave” toys and may even have the breaker panel in there (like my house).

Pre wiring a NEMA 14-50 will cost all of $40 in a garage at time of construction. If that. If the pre wire is just pulling cable to a box (which is what a law would probably mandate since you don’t know if you’ll want to hard wire a charger or not), then it’ll cost $20 extra.

Yes, this is a great idea since it really doesn’t cost that much extra at all when done at construction time. Frankly, the bigger builders will start to do this themselves soon anyways as a marketing feature. New homes have been pre wired for CAT 5 for a while now with no laws requiring this.

If it is that cheap – of course, install one per parking stall. That is adaptable for everything from Tesla to Clipper Creek plug-in models and others.

Big difference between state and local mandates, and a federal mandate. That’s the way some conservatives would see it, I think.

As a local building code, I’m for it. Shoot, its the local building codes that do much worse, like setting perc rates on septic to unobtainable levels. Electric codes, for things like GFI, have forced much higher costs to be passed on than a NEMA outlet and some 10 gauge wire.

I’m studying City Planning and local planning codes are mostly based off of the needs of a local area. This code must really mean that the number of EV’s is so common that they need it to make sure everyone has a place to charge. I do support this bill in that we had a 220 volt plug put in our garage for $200 for a giant space heater but it could also be used for a EV or plug in.

I did remember asking our local planning officials about EV’s and didn’t understand much about it with all the EV’s myths floating around and that EV’s and plug ins are very rare in my area. Ev’s would have to get more common at least for the local officials to see them every day to want to do something about then.

I agree that local zoning codes should be left to local governments. Localities in the US are vastly different, so the Feds should not get involved in this issue. Having said that, it does not make sense at this time for local governments to mandate an extra expense (no matter how minimal) on all new homeowners so that a few (1%? 2%?) can save some money. When EV use is commonplace, then it will make sense. Just not yet.

Actually, this effort will be driven by the builders, not the local governments. Builders will offer the options, buyers will opt in, more and more builders will offer it, some will start including it as standard equipment, and then the others will jump on the bandwagon to stay competitive. This is how markets operate, local governments don’t need to stick their noses in it.

Unfortunately government really does need to step in. Retrofitting is much more expensive, to the extent that the cost becomes a significant barrier to adoption.

If the current situation were healthy, libertarian arguments could have some merit, but I don’t think they do. The current situation is unhealthy. For pragmatic reasons we allow people to be poisoned for the sake of the economy and convenience.

Now, if you want to be friendly you can have a taxpayer-provided fund to pay the mandated costs that you then recover later from EV owners who pay a surcharge on EV registrations.

You are talking about adding to a new home that should last at least 50-100 years. What do you think the chances are that an EV ends up in the garage by 2050 or 2100? We are talking about $200 vs a higher future expense. This $200 is not like spending it on a swimming pool, it will be passed on to the next buyer as well.

Actually Aaron said it in jest but the only way to do it is call it something other than a pre-wired EV outlet. Otherwise unfortunately it does upset the masses even if it is for the long term good of future owners.

Don’t forget to link to your earlier article, where there is *voluntary* language laid out in the guide for cities to use in their pre-wiring code.

Anyway, I have mixed feelings on this. You are, in effect, picking a winner. What if the new owner wants a NG vehicle? Why should they have to pay for this? Or, what if they’re not going to use their garage as a garage? Now you’ve pre-wired the outlet to the wrong place, and have to do it again anyway.

On the other hand, I totally get the cost savings down the road. And I love encouraging EVs. I’m about to add a 40A breaker and plug for our EV in the next few weeks, but for us that’s easy as it’ll be all of three feet from the main panel. In our carport. Because our garage is a shop/storage. So if it’d been mandated to be in the garage/shop, then… useless for us. In our case, even as EV owners, I’m glad it wasn’t mandated.

As much as I would like all new homes mandated to have a rough in for a charging station, making it mandatory for new homes is incredibly short sighted. Maybe in 5 or 10 years, but not now, given the current paucity of electric cars and the residual ill will. The Volt hatred is abating, don’t give the trolls another reason to bash my car.

OK, you’ve convinced me. I’m in agreement. Strike my “mixed feelings” comment above.

KenZ, I think we have to keep haranguing each other, there is no “convinced me” on the net. We HAVE to keep arguing!
How about if I rant for a while about “free choice!” and “no unfunded mandates!” and you hit me upside the head with “Narrow minded curmudgeon!” and “You wouldn’t recognize a good idea if you tripped over it in your front yard!”
Feel free to improve my admittedly amateurish suggestions.

Well, the part that convinced me is simply that it’s too premature. Yeah, houses are around for a long time, but… why push it now. You’ve convinced me that we should wait until EV penetration is a little deeper (like, say, in Palo Alto….). Then write the code upgrade to include both new construction AND any home modification that requires a service upgrade, or a solar upgrade, or something like that. The counter point is: you are now asking a lot of people if their service to their house is, say, 100A, and they’re remodeling their kitchen, and now you want them to add a 40A relay, so now they have to upgrade the entire panel… this is the argument for doing it on new homes BEFORE you have your main panel. OK, fine, so make it new homes and any remodel that requires a new panel and any remodel that increases installed breakers to within 90% of the panel capacity. But still, it’s too premature to mandate. The MOST I would do is the following: require the panel sizing to accommodate an EV and/or properly sized solar system. If you’re adding a solar system, there’s some spec about how… Read more »

I’m not sure I’d REQUIRE this in all new homes. People should be able to built their houses the way they want, as long as they are safe. The biggest expense here will not be the added EV circuit itself, it will be the much larger service and panelboard required since the EV circuit must not be added on top of the house load.

As long as we’re requiring 100 amp circuits for the Tesla High P ower connector, are we also going to require a 3/4″ NPT black iron pipe for the CNG home refueler? Is it more likely the homeowner will own an EV or will own a Cheaper to Operate CNG vehicle?
Which car will use less natural gas, the CNG vehicle directly, or the TESLA model “X” that just happens to get all of its juice from a NG power plant miles away, with no waste heat reused, unlike the more efficient CNG vehicle in the wintertime, where the waste heat is put to good use.

I love this “Model Home”. A toilet at the bottom of those stairs when you’ve really got to go.

A window fan next to the flat-screen-tv is nice too, as well as the bedroom fireplace. I think this is one of the few rooms with electricity anyway so the home probably only has 110 volts for charging the car. Its better than nothing.

OR we do like Austin… Offer -50% cost & installation from the energy company. Those that do, get it, those that don’t, save money from not being forced to get it.

I got my install done as a 240 plug so I could move and take the charger.