Sub Panel Size

[Derek Tuchscherer]

Good afternoon to all the Creekers out there! I am fairly new to the forum...well, new member, but been following along as a lurker for quite a while. And I have a question for you all. I am currently planning out running power to my newly build garage/shop. it is 18' x 24'. My question is this, What size subpanel should I put in??? Will a 60 amp be sufficient or do I really need 100 amp sub. I essentially want 1 circuit for lighting, 2-3 circuits for general outlets and one 220 circuit for a small heater. I do not have any 220 volt tools so this is not a major priority for me. What do you all think? One elctrician has told me 60 amp would be more than enough and another said I should have 100 amp. What should I do????

[Dick Bringhurst]

I put a 100 amp in mine. Sounds like you could get along (for now) with a 60 amp. BUT that is now. You need to consider the future expansion needs and I'll bet you a dollar to a donut there will be expansion needs. Dick B.

[Tyler Howell]

Derek,
I'd do at least 100 amp service now.
A number of your 100 amp panels are actually cheaper than the smaller ones because they are so common.
I suspect that many of your stationary tools can be converted to 220 now for a cooler, more efficient operating system.
I don't think you will be disappointed and there is more room for expansion.:cool:

[Paul Kinneberg]

I would put in a 100 amp the cost is minimal if any, and having to much will not be an issue where as not having enough would be. Also I would consider having two lighting circuits you will be running power tools if all the lights go out it could be problamatic by spliting them I beleive you will reduce the risk of a mishap.

[Derek Tuchscherer]

Thanks for the responses,

As of right now the only hesitation I have with going with 100 amps is the costs associated. I am upgrading the current 100 amp house panel to 200 amp, therefore I can use the 100 amp panel in the garage. So the difference in cost between 60 amp and 100 amp will be the 100 amp breaker for in the main panel, and the increased size and cost for the cable to the subpanel. I am estimating $75-100 dollars for the 100 amp breaker and the cable difference would be $7.50/foot for the 100 amp cable vs. $4.85 for the 60 amp cable, and I need approximately 60' of cable.

As far as two circuits for lights...the lighting will be on it's own circuit as it is. The only way these should go out is if i were to trip the main breaker.

[Kent Fitzgerald]

Welcome, Derek, and congrats on the new shop!

I think the 100 A breaker should run more like $40-60. The price difference in cable works out to about $150, which I think is money well spent. A 60 A supply would probably be enough, but going to the higher amp service gives room for future expansion, and it will produce less voltage drop.

If this is going to be an underground run, I would definitely go with the 100 A service, becasue the labor to re-do it will be much greater than the initial outlay for materials.

[Jeff Horton]

I take a different tack on this (whats new). Yes 60 amps is plenty. Odds are slim of you ever running enough at one time to pull close to 60 amps. What you really need to think about is how many circuits will that 60 amp panel have?

Sure you only need __ cicuits now . But if you are remotely serious your needs will grow and remember that each 220v circuit will take 2 slots out of your panel. Suddenly your out of space! So go with a panel that has as many slots as you can get.

Now, after saying that, I would still do the 100 amp panel. You will never regret it down the road. But you might the 60 amp. If you do it will end up costing you more than putting the 100 amp in now if you afford the difference that is. It's really the smart money.

[Bruce Wrenn]

Another thought. You could get a 100 amp panel without a main breaker. Then using a 100 amp breaker (labeled as "main") feed the panel. You would give up two spaces in panel though. I would definately get a panel with at least 20 spaces in it. Life changes and so does your electrical needs.

[Steve Rowe]

I have 200 amp service to my 1000 sq ft shop. I have absolutely zero worries that I will run out of power. Don't size your service based on what your current needs are, base it on what your needs may be in the future. The incremental cost difference between 60 and 100 amp (or even 200) should be relatively small. You could easily be regretting paying for a larger service in the future in addition to the service you add today if you make it too small.
Steve

[Bruce Shiverdecker]

I put a 100 Amp sub feed panel and fed it (for now) with a 70 Amp Breaker. I can expand it if necessary.

Bruce

BTW, my TOTAL shop is now 200 Sq/Ft.

[Greg Narozniak]

I installed a 125amp GE "Shop Panel" fed with a 100amp breaker. My sub is mounted right next to my main panel so I only needed 3 - 4 feet of feeder cables. I added 3 20amp 220v circuits (TS, cyclone, jointer) I also ran 2 sets of 20amp 110v circuits, 1 15amp 110v circuit for the overhead cord reel, 1 Single 20amp 110v mounted between the overhead doors, and will be adding another set of lights off one more 15amp 110v. Will probably add another 220v in the future just for convience.

It is amazing how fast the box fills up. I can always change to slim line breakers (The panel came with with 4 full size 20amp 110v breakers) but for the $150 extra it would be a no brainer for me to know you will have enough for the future.

When I my old house's main panel was upgraded I could have went with a 32 slot or a 40 slot. I went with the 40 to the disagreement of the electrician helping me. When we were all done he looked and said "I guess it's a good think you went with the 40" as I had used up 36 slots. :)

[Jeffrey Makiel]

100A seems unnecessary and costly especially with the recent cost increase of copper recently. Aluminum conductor is an alternative, but not my preference.

I have a 50amp subpanel and it is more than adequate. I would also like to qualify my opinion by stating that if the machine can run on dual voltage (120 or 240), I wire it for 240V.

Here's the lineup for me:
3 hp Unisaw (18A at 240V)
1 hp jointer (8A at 240)
2 hp edgesander (10A at 240)
2 hp dust collector (10A at 240V)
2 hp bandsaw (10A at 240V)
1 hp radial arm saw (8A at 240)
1 hp drill press (14A at 120V)
3 hp routertable (15A at 120V)
12" portable planer (15A at 120V)

I kept the lighting circuits as direct feeds from the main panel, this eliminated any flicker during machine startup.

I usually run only one machine at a time plus the dust collector. This is less than 30A. At most, two machines plus a dust collector at less than 35A. Also, the amps shown above are full load rating of the motor which is seldom the case.

Unless I was planning on running something huge like a 36" wide belt sander with a rotary phase converter, I do not see me ever upgrading my electrical panel. My shop has been in use for over 15 years and is only used as a hobby. It is the same size as yours ~17' x 27'.

-Jeff :)