Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Charging station in detached garage

Sophias_dad

Supporting Member
Supporting Member
Jul 29, 2018
1,528
1,610
Massachusetts
Looking again at your latest picture, it seems that's 3/4" EMT, not pvc. I was surprised to see it doesn't matter much, you are limited to 6awg through that conduit. The only thing it gets you is the ability to use XHHW instead of THWN because XHHW's insulation is slightly thicker and won't comfortably fit in 3/4 PVC conduit. 6awg should get you 65 amps at the subpanel in the garage.
 

Sophias_dad

Supporting Member
Supporting Member
Jul 29, 2018
1,528
1,610
Massachusetts
Is 65 amps sufficient for coach house (i.e. 1 bedroom suite)and charging station?
65 should be fine, particularly if you didn't claim more than 32 amps for charging. The big limiters will be hot water and space heating. For space heating/cooling you might want to look into a mini-split heat pump that will heat reliably down to well below freezing outdoor temperatures, rather than resistive heat. Of course, if you have natural gas out there, go gas for both.
 

CaliX

Member
Feb 14, 2016
546
360
Los Angeles
We have been longtime Tesla owners we have now have a S and a Y. I was in the same boat as you. Because of the city codes my only option was running it underground. I sucked it up and ran a line 100’ under a driveway and walkway it cost 13k. I’m not selling anytime in the foreseeable future so it was worth it for us. I did about choke when I got the original quotes. Now that I have it setup it’s a breeze to charge the cars. Good luck.
 

jason330i

New Member
Mar 1, 2021
1
1
Los Angeles
Hello, I decided to go big with a 125A sub panel in our detached garage. Had to trench wires underground, cut concrete, etc. Plan to charge Model Y and Cybertruck in the future.
 
  • Like
Reactions: CaliX

jezwiggles

New Member
Apr 13, 2021
1
0
PA
Hi all - new here, but really appreciate all the comments and learning a lot. I have a detached garage with existing buried PVC conduit (2018) running right into basement of the house (25 feet). Can I run 6-3 AWG wire in there and use the existing wires to pull? I would then add the 60 amp double pole breaker. The wire that is available right now is Romex 6/3 Type NM-B. Was hoping to use existing PVC conduit that is buried then run the wire in the unfinished basement to the panel. The quotes where we live are extremely high (>$2500). Was also concerned there might be too many wires in there, but could eliminate 2 that operate a heater the previous owner put in. Thanks all...
 

jcanoe

Active Member
Oct 2, 2020
3,418
3,471
Maryland
Hi all - new here, but really appreciate all the comments and learning a lot. I have a detached garage with existing buried PVC conduit (2018) running right into basement of the house (25 feet). Can I run 6-3 AWG wire in there and use the existing wires to pull? I would then add the 60 amp double pole breaker. The wire that is available right now is Romex 6/3 Type NM-B. Was hoping to use existing PVC conduit that is buried then run the wire in the unfinished basement to the panel. The quotes where we live are extremely high (>$2500). Was also concerned there might be too many wires in there, but could eliminate 2 that operate a heater the previous owner put in. Thanks all...
What is the diameter of the conduit? What did you mean by "The wire that is available right now"? Is this the wire currently inside the conduit or the type of wire that you found to buy at the local supplier? NM-B can be installed in conduit where protection is required but you can't use NM-B in conduit underground.

Can Romex (NM-B) cable be run through conduit?
 

Rocky_H

Well-Known Member
Feb 19, 2015
6,765
8,352
Boise, ID
@jcanoe beat me to it. NM-B is not allowed to be run in locations that are considered "wet", and underground conduit is always considered that, so it should not be allowed in there.
I'm not as familiar with conduit fill calculations. There are specs on with a certain diameter of conduit, there are tables of how many wires of what size gauge can be put in there. I would think that is a possibility, though. Especially if you are pulling through to remove the Romex, with just regular individual wires, that might have room. If you only need the 240V connection for charging, then you would just need the two hot wires and a ground and no neutral would be needed, which would be more space in the conduit. Without the diameter of the conduit, no one here can give you an answer yet.
 

Sophias_dad

Supporting Member
Supporting Member
Jul 29, 2018
1,528
1,610
Massachusetts
Hi all - new here, but really appreciate all the comments and learning a lot. I have a detached garage with existing buried PVC conduit (2018) running right into basement of the house (25 feet). Can I run 6-3 AWG wire in there and use the existing wires to pull? I would then add the 60 amp double pole breaker. The wire that is available right now is Romex 6/3 Type NM-B. Was hoping to use existing PVC conduit that is buried then run the wire in the unfinished basement to the panel. The quotes where we live are extremely high (>$2500). Was also concerned there might be too many wires in there, but could eliminate 2 that operate a heater the previous owner put in. Thanks all...
Really should have started a new thread for this!

What does 'available right now' mean? Is that already through the conduit? If so, I'd disconnect it and run individual conductors through the conduit. Whether they continue in your house in conduit to your main panel is up to you, there are connection methods even for such large wire that could connect NM-B in your basement to conductors-in-conduit. Once at your garage you'll probably want to keep it in conduit until it reaches a new subpanel for distribution within(you'll need a fourth conductor(ground) for that, but I don't think it has to be the same size. In fact, it might be possible to pound a new ground rod in at the garage subpanel and avoid the extra conductor(not sure on this one, I'm sure someone will know)

As far as what you can send through that conduit, its limited only by your conduit size. Eventually you need to start thinking about the available capacity of your main panel.
 

Mrbrock

Member
Mar 26, 2020
997
689
Napa, CA
Can a new wire be run outside around the house from panel to existing conduit? This would be in conduit but above ground.
As long as you and any significant others are ok with a 1” diameter piece of pipe running around the outside of your house. It’s how most solar systems wires come off the roof and tie into electric panels.

If you want the cleanest look you leave the existing wiring in place for the sump and then add a new breaker for a garage panel and trench wires. There are some direct burial wiring options but this limits the ability to replace wiring in the future by pulling through conduit. And you have to dog deeper than using conduit.
 

Hippo25

Member
Feb 18, 2021
43
42
British Columbia
Looks like my thread has diverted a bit. No problem, we can share this thread.

I got a quote from an electrician to dig trench to detached garage, run a new line from panel to garage, install subpanel in garage, and install charger in garage. $3500 with permits.
 
  • Like
Reactions: CaliX

Canefan456

Member
Sep 26, 2020
110
114
Atlanta
I have a very similar situation with my detached garage. Distances are very similar. We ended up having our power meter on the outside of the house replaced with one that has the capacity to add additional breakers at the meter. This meant that we did not have to tear up our basement running the line through the ceiling and penetrating the outside of the house. The distance from meter to garage was shorter as well going this route. It did involve some coordination with the power company as they had to come out and shut off power to the house while the electrician replaced the meter. An inspector had to then come and inspect his work before the power company returned and turned the power back on. All told, the power was down for around 90 minutes. Cost for entire job which included running 6AWP wire from meter to garage underground was $2350.
 
  • Informative
Reactions: mrau

Hippo25

Member
Feb 18, 2021
43
42
British Columbia
Update to my original post...

I got a couple more quotes: one for $4000 and another for $1800 (but does not include trenching). Both are permitted and inspected installations. Was favoring the $1800 quote, not because it's the cheapest but because this was a highly reputable electrician. I searched around for a labourer to dig the trench but no success. So since I'm still waiting for my MY and instead of sitting around and continuously refreshing the estimated delivery, I decided to take on the task of digging the trench. My family helped and we managed to complete the trench. It was hard work but good learning experience on using new tools (jackhammer, auger). Electrician came to have a look and approved; he will do the electrical installation next week.
 

Products we're discussing on TMC...

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top