Detached Garage into Workshop help

[RobLS]

Hello.
Newish here.

I live in a smaller house that has a detached garage in Houston, TX. I’ve been making it work when it comes to woodworking in there.

I have a 100amp electrical panel. I have in total 2 electrical outlets in the garage. One at the top where the garage opener is plugged in and one on the back wall, your typical 120v setup. There is one central light in the garage as well for a screw-in bulb.

When starting out I used to frequently trigger the breaker, typically when trying to use dust extrication and a shop tool like a table saw or thickness planer at the same time. It turns out there was a 15 amp breaker going to the garage, and after some consulting, we switched it out for a 20 amp. Now it will trigger only when I am trying to remove more material in that planer or if I am ripping dense boards or thicker boards.

So now to what I’d hope to accomplish for this space. I want to transform it to a true workshop.
I would like to have outlets on all my walls, particularly being able to handle more power for higher voltage tools in the future.
I would love to have great lighting throughout the shop. Using a single point light fixture has been rough.
I also have plans to have an electrical vehicle as well and I know that could benefit from a higher voltage offering for it charger.

I am assuming that I would need to upgrade the power coming into my electrical panel and I am unsure of that and if so where to begin with that.
Secondly, would making a sub-panel just for the shop make the most sense?

I can do the handy work with installing the lines, outlet and such, even the sub panel if needed. I just want to make sure I am doing things right and in a safe manner.

I also wanted to finish this post thanking those who take there time to read this and to give help.
I saw this section of the forums and felt like this fell under that category.

Looking forward to getting to know you fine folk.

Rob

 

[onocoffee]

How old is the house and wiring? When you changed the breaker from 15A to 20A you want to be careful. Did you check the wiring before changing the breaker? Typically, 15A circuits will be wired with 14 gauge wire. Code for 20A is 12ga wire. The larger gauge wire carries more current. I would suggest going back to a 15A breaker. If not, be careful how much load you are running at one time. The extreme result would be overheating the jacketing of the wire, meltdown, fire and total loss of your home. It does happen.

What you might consider is contacting your electrician and having them run a line and install a sub-panel in the garage that you can then break out into different outlets with 20A circuits. That will be much safer. It's what I did in my garage.

Years ago, my electrician ran 3AWG aluminum wire to the garage from a 60A breaker in the main panel to an 8-space sub-panel in the garage. From there, I built a breakout panel running several different outlets to power whatever I needed, both in 220v and 120v.

 

[RobLS]

How old is the house and wiring? When you changed the breaker from 15A to 20A you want to be careful. Did you check the wiring before changing the breaker? Typically, 15A circuits will be wired with 14 gauge wire. Code for 20A is 12ga wire. The larger gauge wire carries more current. I would suggest going back to a 15A breaker. If not, be careful how much load you are running at one time. The extreme result would be overheating the jacketing of the wire, meltdown, fire and total loss of your home. It does happen.

What you might consider is contacting your electrician and having them run a line and install a sub-panel in the garage that you can then break out into different outlets with 20A circuits. That will be much safer. It's what I did in my garage.

Years ago, my electrician ran 3AWG aluminum wire to the garage from a 60A breaker in the main panel to an 8-space sub-panel in the garage. From there, I built a breakout panel running several different outlets to power whatever I needed, both in 220v and 120v.

This house is about 20 years old which I know I should be getting the panel inspected anyways. I had a friend who checked things to let me know if I should be fine with going to a 20. Then on a separate occasion with another guy verified I should be good with that as well.

Thank you for your input for that as well as the other information.

 

[Cheese]

First off  [welcome] to the FOG.  [big grin]

To put things into perspective, I just recently built a 750 sq ft 2 story detached garage & had been living with a 280 sq ft single story garage for the last 30 years.  [crying]

If the main electrical panel is inside the house (typical), remember it's the length of wire from the electrical panel to the garage that ultimately determines the amp rating of the electrical service for the garage.

If 14 ga wire runs from the house to the garage, that wiring while nominally rated at 15 amp service, needs to be derated for continuous service and also needs to be derated for total wire length.

I believe 14 ga wire/15 amp service needs to be deregulated to 12 amp for continuous service, while 12 ga wire/20 amp service needs to be deregulated to 15 amp for continuous service plus you need to factor in the wire run length.

For example, if the main 120/240 volt wire enters the electrical panel on the north side of the house and enters the garage from the south side of the house, that entire length of wire needs to be factored into the calculation.

It's great that you're competent to upgrade the electrical wiring as it's not difficult and you'll save a bundle. Just make sure to follow the local electrical codes as they were developed for a very good reason. I wire all my own stuff and have had no issues over 40 years.

For lighting use LED's...don't even think of alternate light systems. Between the amount of light projected and the expense that lighting costs...nothing else is even close.

So now you're twisting the knife... [big grin] ...the inclusion of an electrical vehicle charging station really complicates the situation. EV charging on 120V takes hours and that's ok if you don't use the vehicle much. Check on charging times for 120V charging...it can take days.

Most folks if considering EV charging capabilities in their garage, go for the 240V option which significantly reduces charging hours. That's one of the reasons I opted for a separate 200 amp service panel being installed in the garage. Besides, using the 240V option allows you to choose the charging hours when the charging rates are the cheapest. It's usually between 12:00 and 5:00 AM.

This is not a definitive list of suggestions...just a conversation starter.  [smile]

 

[RobLS]

First off  [welcome] to the FOG.  [big grin]

To put things into perspective, I just recently built a 750 sq ft 2 story detached garage & had been living with a 280 sq ft single story garage for the last 30 years.  [crying]

If the main electrical panel is inside the house (typical), remember it's the length of wire from the electrical panel to the garage that ultimately determines the amp rating of the electrical service for the garage.

If 14 ga wire runs from the house to the garage, that wiring while nominally rated at 15 amp service, needs to be derated for continuous service and also needs to be derated for total wire length.

I believe 14 ga wire/15 amp service needs to be deregulated to 12 amp for continuous service, while 12 ga wire/20 amp service needs to be deregulated to 15 amp for continuous service plus you need to factor in the wire run length.

For example, if the main 120/240 volt wire enters the electrical panel on the north side of the house and enters the garage from the south side of the house, that entire length of wire needs to be factored into the calculation.

It's great that you're competent to upgrade the electrical wiring as it's not difficult and you'll save a bundle. Just make sure to follow the local electrical codes as they were developed for a very good reason. I wire all my own stuff and have had no issues over 40 years.

For lighting use LED's...don't even think of alternate light systems. Between the amount of light projected and the expense that lighting costs...nothing else is even close.

So now you're twisting the knife... [big grin] ...the inclusion of an electrical vehicle charging station really complicates the situation. EV charging on 120V takes hours and that's ok if you don't use the vehicle much. Check on charging times for 120V charging...it can take days.

Most folks if considering EV charging capabilities in their garage, go for the 240V option which significantly reduces charging hours. That's one of the reasons I opted for a separate 200 amp service panel being installed in the garage. Besides, using the 240V option allows you to choose the charging hours when the charging rates are the cheapest. It's usually between 12:00 and 5:00 AM.

This is not a definitive list of suggestions...just a conversation starter.  [smile]

Thank you for such a warm welcome and your input!

My panel is not inside the house, it is on the side of the house. About 15-20 feet from the garage, specifically to where the first outlet is. I tried attaching a picture but I get an error with no reason why trying to post it.

I like the idea of the sub panel with a 200 amp rating.
But I am limited by the 100 amp rating of my main electrical panel right?
Does the utility company have to come out and bring in more power to the house to allow more to go to the garage/shop? I plan to keep the house ratings the same for now since I don’t plan on opening up the walls for that wiring. The detached garage has open walls so I can route cable in there and put up panels.

 

[luvmytoolz]

After many years of putting up with an 80A input to the board (after utility company changed over all the transformers and wiring in the street) but only a total of 15A supply from the board to sockets and lights in our 60+ year old house, I had the entire property rewired, and had a 32A sub board with two separate 15A outlets in each of the sheds.

Absolute best thing I ever did. Never have to worry again about the breaker tripping if the wife uses the kettle when I'm using tools outside, or not being able to use dust extraction whenever I used my thicknesser.

Good, decent and safe power cabling is gold in a workshop! And most exciting is that I can now use my Jet combo jointer I bought 5-6 years ago, but was just too much for the power board, so it sat covered up in the back corner of the shed.

I saw some of the old and perished rubber insulated wiring pulled out from the roof and walls, it's seriously a wonder our house never burnt down! Also explains why we kept blowing light globes so much.

 

[rvieceli]

[member=82974]RobLS[/member] Rob welcome to the FOG

Cheese actually had his power company (POCO) drop a new meter and add a separate service drop to his garage.

Some poco will do that others won't or they make you do very specific things to make it happen.

So you have some options. Drop a new meter and service at your existing garage. advantage is plenty of power May be costly and get you commercial rates

Upgrade your service at the house to 200 amps and then run a subpanel to the garage. Workable and not that hard. check with your poco.

another option would be to keep only one meter but install a 200 amp service panel and a new meter on the garage then connect your old house panel as a sub panel to the one in the garage. Advantage would be only one service at your address and the larger capacity panel would be where the EV charger would be located.

You would need to get in touch with your poco for those options.

Ron

 

[jeffinsgf]

My panel is not inside the house, it is on the side of the house. About 15-20 feet from the garage, specifically to where the first outlet is. I tried attaching a picture but I get an error with no reason why trying to post it.

I don't think I've ever heard of a service panel being on the outside of the house. Just from a security point of view, I would hate that. Unless it has a very secure lock, anyone could walk along and shut your house down. And with a lock, if you have a breaker trip you have to find the key and go out in the weather to reset.

It might be a major undertaking, but I would move the main panel inside, increase it to 200 amp service and run a 100 amp sub-panel to the garage.

 

[Packard]

Just one question:  Does the garage currently have air conditioning?  I was scanning for that in the posts and I did not see it.

 

[cpw]

I don't think I've ever heard of a service panel being on the outside of the house. Just from a security point of view, I would hate that. Unless it has a very secure lock, anyone could walk along and shut your house down. And with a lock, if you have a breaker trip you have to find the key and go out in the weather to reset.

It might be a major undertaking, but I would move the main panel inside, increase it to 200 amp service and run a 100 amp sub-panel to the garage.

I think this is a regional thing.  Mostly panels are inside the garage here, but some people do have a disconnect outside.  The meter is on the outside, so if someone is so inclined; they can just pull the meter on you.

I am surprised a house that is only 20 years old has a 100amp service.  Around here that is common in the houses from the 60s and 70s, but everything 80s/90s and later is 200 amp.

You should be able to run a subpanel off the main panel, without actually upgrading the service.  The main breaker is generally less than the sum of the individual breakers.

If you're seriously into woodworking, the minimum I would want is 60amps.  20 amps for a dust collector, 30 amps for a large power tool, and some head room for a convenience circuit and lighting.  And since you are in Texas, maybe think about having a mini split eventually.

 

[Packard]

From the Internet:

Houston has a subtropical climate with hot and humid summers and warm winters. […] Hot season: June 2 to September 22, with average daily highs above 89°F.

For me, this would not make a suitable workshop without A.C.

Unless it is well-insulated, I’m not sure a mini split would get the job done.

 

[Cheese]

To build on what Ron & CPW have already mentioned, the houses in the Twin City area where I live, all have 250 amp service connected to the electrical service mast. So getting a larger amp electrical service is as simple as changing the electrical service panel on the inside/outside of the house. I suspect it is the same in other communities as swapping out complete overhead service lines from the electrical poles to the individual service mast would prove to be expensive and inefficient as folks are always upgrading their electrical service.

Contact your local POCO to find out what amperage is at your service mast.

If you decide to do a separate drop to the garage, they'll install a meter on the garage and you'll then pay 2 meter charges every month.  [sad]

A separate electrical service for the garage is nice if you decide to add welding to your portfolio or if you want to charge the EV at reduced electricity rates. Again, check with your POCO and find out what options they offer for EV charging.

A typical baseline is EV Level 1 charging uses 120V and charges in 12-24+ hours, while Level 2 charging uses 240V and charges in 3-8 hours. Level 1 charging only adds 5 miles to your battery every hour.  [blink]

 

[RobLS]

Good day to you all.

And a lot of info to go over. But I can’t believe I forgot about temperature of the garage. It is one of my biggest hurdles in the summer. Currently my strategy has been main garage door open and back door open with a fan to create a breeze, and hydrate haha.
I would love to have climate control in there at some point. But before that I would need to semi finish the walls which means insulation.
So yes, eventually power for AC.
I used to primarily do mechanical work, some on cars but specifically on motorcycles. Some of that will continue but I am shifting further into woodworking. Actually selling a couple motorcycles right now to make more space, one about to be sold tomorrow hopefully and the ad for the other coming soon. Will probably end up putting my 2 remaining (much smaller) motorcycles in a separate shed later.

As far as the location of the electrical panel, I too thought it was odd. I am trying to recollect all the places I’ve lived in and they all seemed to have the panel in the garage and if not in the garage it would be the house.
Adding on top of this, it is on the side of the house facing the street, so not behind our fence. Also the side of the house that gets the most sun. And being in Houston we get quite the weather so it gets beat up by all the elements.

But I will certainly reach out to the power company and see what options they have. If I had a full fledged business with woodworking I could see the benefit of having a separate meter and not having to work out what is home use vs business use. But I am not at that level yet. So I think I would end up doing a main and a sub and working with the poco will hopefully determine if the garage is the new main or if the houses main gets upgraded so I can install a sub.

A thing I gotta add. So far this has been a great and helpful first experience on this forum. I look forward to being more involved here. I got my first Festool stuff late last year as a surprise gift from the lady and boy is it helpful.

 

[Packard]

An amusing (to me) sidebar:

The company where I used to work added several spot welders as we had taken that operation in-house whereas in the past we contracted that work out. 

Strangely, despite the rather hefty additional electrical use, out electric bill did not increase in any noticeable amount. 

It turns out the the service meters were unable to react quickly enough to record the short duration electrical draw.  Apparently, it was only when several welders cycled in quick duration (that mimicked continuous draw) did the electrical usage get recorded. 

That was going back to the 1990s.  Perhaps solid state meters would do better.

 

[peter halle]

Just one question:  Does the garage currently have air conditioning?  I was scanning for that in the posts and I did not see it.

MY house has it on the outside.  Yes, we are in a remote area so security isn't an issue.  But Asian lady bug lookalikes are.  Several homes have had to replace their exterior panel boxes when those little critters took up residence and shorted / cooked the box.

My house is a smaller cape cod and having the box outside really helps by not having it mounted in a bedroom wall.

Peter

 

[smorgasbord]

I like the idea of the sub panel with a 200 amp rating.
But I am limited by the 100 amp rating of my main electrical panel right?
Does the utility company have to come out and bring in more power to the house to allow more to go to the garage/shop? ...

Please don't take this the wrong way, but you asking these questions tells me that you're not experienced enough to do the work you originally posted about wiring up sub-panels and the like. Unless you want to take the time to crash course electrical requirements, code compliance, the permitting process, etc., you should be hiring a professional electrician.

 

[RobLS]

I like the idea of the sub panel with a 200 amp rating.
But I am limited by the 100 amp rating of my main electrical panel right?
Does the utility company have to come out and bring in more power to the house to allow more to go to the garage/shop? ...

Please don't take this the wrong way, but you asking these questions tells me that you're not experienced enough to do the work you originally posted about wiring up sub-panels and the like. Unless you want to take the time to crash course electrical requirements, code compliance, the permitting process, etc., you should be hiring a professional electrician.

I get where you’re coming from.
I am looking for direction when it comes to code/standards with power coming in and dividing that up, coming up with the plan.
Once the plan is in place, I can do the physical work. Which is why I had the concern of making sure I did things right.
I asked the question because I am not going to assume. I also spoke to a licensed electrician a couple months back and I didn’t feel comfortable with the information I got from him, which he just suggested to me to upgrade past a 20 amp for the garage and add more outlets just off that and it should support an electric vehicle.

I didn’t know where to go from there in making sure things were done right, such as what was provided up above about reaching out to the poco.
Through all of this, trust that I still know enough to consult licensed professionals where needed.

Again, the post is intended for input for direction, recommendations as well as some information. Being a forum I was expecting from potential professionals on here, people who have gone through this themselves or even people just giving their two cents.

Than You for your input

 

[smorgasbord]

Again, the post is intended for input for direction, recommendations as well as some information.

OK, find yourself a good professional electrician and get a quote for:
• Upgrading your service from 100 amp main to 200 amps.
• Adding a dedicated code-compliant EV charging circuit. That would be 220 volts and at least 40 amp rating (which means you cluld pull 32 amps continuous).
• Adding whatever else you want for AC, lighting, tool power circuits, etc.
• I'd recommend having at least 1 220 volt circuit for power tools in the future.
• I'd recommend the 110 outlets for power tools be 20amps.
• I'd recommend having your previously upgraded circuits re-looked at. They need to be 12 gauge wire, and it's not common to wire up with 12 gauge and yet put only 15 amp breakers in, as your story would have to be to be true. Possible, but given your experience with your previous electrician consultation, concerning.

This isn't going to be cheap, probably at least $2,000. Upgrading the main service and service panel is costly in terms of parts, takes time, including co-ordinating with your electricity provider to shut off power to your house while the main panel is replaced, then turning it back on after inspection (which normally can be done the same day).

 

[RobLS]

Again, the post is intended for input for direction, recommendations as well as some information.

OK, find yourself a good professional electrician and get a quote for:
• Upgrading your service from 100 amp main to 200 amps.
• Adding a dedicated code-compliant EV charging circuit. That would be 220 volts and at least 40 amp rating (which means you cluld pull 32 amps continuous).
• Adding whatever else you want for AC, lighting, tool power circuits, etc.
• I'd recommend having at least 1 220 volt circuit for power tools in the future.
• I'd recommend the 110 outlets for power tools be 20amps.
• I'd recommend having your previously upgraded circuits re-looked at. They need to be 12 gauge wire, and it's not common to wire up with 12 gauge and yet put only 15 amp breakers in, as your story would have to be to be true. Possible, but given your experience with your previous electrician consultation, concerning.

This isn't going to be cheap, probably at least $2,000. Upgrading the main service and service panel is costly in terms of parts, takes time, including co-ordinating with your electricity provider to shut off power to your house while the main panel is replaced, then turning it back on after inspection (which normally can be done the same day).

Thank you for the additional info and recommendations.
I had been anticipating a price in that ballpark, overall the cost will be above that anyways since I have more renovation to do beyond electrical. The benefit I have is time, I don’t need to do the entire garage/shop renovation in one go. I hope to get the power company to do their thing before the heat of the summer.

And as for the wiring in the garage, I plan to rip that out and run new. And plan for the future.
Regarding 220 in the shop, my initial idea would be to have a 220v circuit on each side of the shop to cover larger tools in the future as well as handle an electric vehicle.

However nothing is set in stone yet. I have the rough idea of power I’d like to have. And now that I know to reach out to the power company, I can get an official plan put in place. From there I can design the layout of things and then see what circuits go where.

I am already grateful for the help here. For example; I had already forgotten about power for ac in the future and being in Houston that would have been unfortunate to have missed that in calculation for power needs.
Sometimes focusing on the details of the project you’re working on you forget to look at the big picture. It helps when you can get additional input.

And to ramble a bit more, my expectations are low for when I talk to the power company here. I am from California and I have noticed a drop in standards for building out here in general. Everything from electricity to plumbing to general construction has just been a lower quality out here.

Ramble over, for now.

 

[smorgasbord]

1) The power company is not going to upgrade your service for you. You need to hire an electrician to do that, who will coordinate with the power company to turn off power, do his thing, then have them come back, inspect, and turn power back on.

2) Just upgrading the main panel alone will probably be over $1300. That's without new wiring of any kind, just the new line in (if not big enough, which it probably isn't), the new panel, and new breakers to the existing lines. And you'll probably need a panel that can hold more breakers than your existing 100 amp, so how that bigger panel fits into whatever space the old panel is there needs to happen, too.