eddie1261
So adding those things up Herb, obviously you know electricity, and I will also assume you wired your studio building. So my question is this. How big a circuit breaker does that studio run on? Knowing that not every piece of gear is not always powered on, and knowing what I typically have powered on at once running on a 15 amp breaker, can I then assume that I could tap off the power in the garage that runs on a 20 and pretty much only powers the garage door opener? (Which, of course, only draws power when it is going up or down.) If I could break off of that it would make life easy if I built that studio building. I'd only have to trench about 10 feet from the garage to bury the conduit. The power in the upstairs studio as it is right now powers the computer and monitor, 2 powered speakers, and a keyboard or guitar amp, depending on what I am doing. I don't pop the 15 amp breaker, so I can't imagine I'd pop a 20! I plan to have skylights for daytime use and the same lamp I have up there now if I work at night. I would use spray foam insulation so it won't be loud.
Really considering this! My local code allows me 200 sq ft without a permit, so I'd go 14x14 (192). And if there are no permits for size, I can have my friend run that electric over without a permit too since the city won't even know I am building. Probably looking at a mini split for HVAC, but still doing research. I don't even know yet if they run on 110 or if I'd need 220 for it. If it does, THEN the game plan changes. Though as I think about a 14x14 room, a mini split seems like WAY overkill. I heat a 12x14 bedroom with a portable heater. Logic would seem like a portable cooler would do the same. Even a 5000 BTU room AC would be way too much for that space. Before my house had central AC I cooled a 16x14 living room with a 5000 BTU window AC and it got TOO cold in there. I have 2 small ceramic room heaters. Room HVAC seems like it may be an expense I don't need to incur.
So.... I have a main service panel with 4 double pole spaces and a 200A main. The house is on the 200 amp lugs fed through. My water pump is on one double pole space, the garage is on another, a surge suppressor is on another and I wired my studio to another.
The studio is wired with #10 UF on a 30a breaker. It's approximately 150 feet or so from the service to the studio. I knew I was going to add heat and air with a ductless mini split. Trust me, you will want heat and air in your studio if for no other reason than to reduce the humidity your gear is living in. However, on cold winter nights and hot summer days, I can work on my music in 68 to 72 degree comfort. Window AC is really loud whereas a mini split is extremely quiet. You don't hardly know it's on which is really nice when you are tracking vocals.
I have a sub panel in the studio wired for 240v. All the normal stuff is on the 120v circuits single pole breakers. I run a pair of computers, a mini fridge (gotta have beer and water you know) and lights plus all the outboard stuff for the studio and a pair of lava lamps. I also feed the pole barn lights and fans from this sub panel. If you decide to get a mini split, get a 240v model since the power drawn is less than the some one in 120v models.
Given the info you provided.... Is the 20a cb for the garage a single or double? If it's a single.... you would want to consider swapping it to a 2 pole to get you 240v to the garage. Your friend ...who hopefully knows how to work with electricity and do things by code.... even though you're not pulling permits.... can look at the wiring and see how difficult or easy it would be switching from 120v to 240v. Going to 240 lets you double the available current and use a 240v mini split. If the garage is fed with #12 UF, it's not difficult to convert to 240v. The key is if you can get proper, code compliant, grounding at the sub panel in the garage. That is seriously important. Not only for safety, but to have quiet gear without those annoying ground loop hums.
Regarding the mini split sizing.... the companies that sell them have room size calculators on their websites. Calculate the room size and insulation values of the walls, and ceiling. There's a size that will be recommended. if it's close to the upper edge of the envelope.... size it up. However, don't go too big or you risk other issues.
Hopefully this helps answer some of your questions. If you have more, just ask.