Wiring a Shop

David Ripley asked on WoodCentral:

“Any good web sites and or books on wiring a garage workshop?”

Clint Serl responded, saying:

“Check the Taunton website. They publish a good one by Rex Cauldwell.”

My response was (more or less; I've since expanded on the original):

If you're looking for how-to information on electrical wiring in general, The Cauldwell book Clint mentioned (Wiring a House) is good, as is another one I've used for more than 30 years; Wiring Simplified, by Richter, Schwann, and Hartwell (I haven't used the same one for 30 years; my current one is the 40th edition based on the 2002 NEC). I recommend having both on hand.

If you're looking for shop specific information, I don't know of any books in particular. I have, however, gleaned a lot of ideas over the years from threads on this and other fora, as well as rec.woodworking, and I can summarize by mentioning a few points to consider:

• Think subpanel. Not so much for isolation from the rest of the house service, but for the added capacity for circuits
  
  
• Plan more 120V receptacles than you think you could possibly use, and then put in twice as many. How many times do you think you'll have access to add wiring? Do it now, while it's easy
  
  
• Similarly, don't think your table saw will be the only user of 240V service: how about a compressor, dust collector, large planer, large jointer, shaper, honkin' lathe, wide belt sander, welder, or other future acquisition? Put in several.
  
  
• Some people have suggested wiring your 240V circuits with 10 ga wire (although on 20A breakers) for future machines that may need the capacity (like 5 hp motors; then put in a 30A breaker, although there's nothing wrong with a 30A breaker from the beginning; it's protecting the wire, not the load). Working with 10 ga is a real pain, but if you only have to do it once…
  
  
• Do you lean sheet goods against walls? Put your receptacles > 48" above the finished floor to keep them free for use. Use Baltic Birch much? Put your receptacles > 60" above the finished floor.
  
  
• What kind of receptacles? Avoid 79¢ big box contractor specials. Spend a couple bucks and buy commercial duty receptacles (I like the rear connect, not back stab, type; no more wire loops for me)
  
  
• A lot of people recommend twist lock for 240V receptacles.
  
  
• Consider ceiling drops for your floor tools that are fixed or frequently moved to areas away from the walls.
  
  
• Extension cords on overhead reels are handy over benches where you sand or use other hand held tools-with-tails.
  
  
• Think zone lighting. Don't wire so that you have to light up the whole shop to tinker with a tool at the back bench.
  
  
• Fluorescent is a convenient, relatively efficient light source. Install lots of them. Right now is as young as you will ever be, and your eyes will never be better. As you get older you will find there is no such thing as too much light.
  
  
• Make provisions for an incandescant light or two, especially for lathe lighting (stroboscopic effect with fluorescents).
  
  
• Don't worry about all of these circuits exceeding the amperage capacity of your panel. You are a one man shop with perhaps an occasional helper. Aside from lighting you'll unlikely ever have more than one big machine plus the dust collector and compressor (kicking in whenever it feels like it) running at one time.
  
  
• In the grand scheme of things, wire is cheap, but not as cheap as some woodworkers who try to skimp on a one-time $500 project which will support several $1000 tools.

Most of these are not my ideas; as I said, I gleaned them from dozens of threads over the years, and this list is not exhaustive. I'll add more as others chime in with their ideas.

I Hope this helps.

Last updated: 27 January 2009