Background: My main service panel is located in my garage on an outside corner wall... ie its not convienent in any way to add branch circuits. I want to add a sub-panel in my crawlspace (40 feet from main panel) to feed a couple of new circuits for outdoor lighting and a hot tub. I also want to add a sub-panel in a detached garage (140 feet from proposed crawlspace sub-panel) and be able to add other outdoor lighting circuits and a pond/waterfall pump from there as well. No heavy shop equipment at all.

Since it is going to be a pain in the *** to wire anything from the main panel, I was only wanting to run one set of wires to feed the sub-panel from the main and then run from that sub-panel to the sub-panel at the detached garage. I know there are the rules about isolating the neutral and ground and all of these intended circuits are going to need GFI protection.

Questions:

1. Is putting a sub-panel in the crawlspace allowed?
2. If question 1 is OK, can a run another sub-panel off the first for the detached garage?
3. If questions 1 and 2 are Ok, would this be MLO type panels with one breaker back at the main only? Or would I need a breaker in the first sub to feed the second sub?
4. My intended loads for each panel would not exceed probably 40 amps and certainly not close to that in continuous operation. With that in mind, what size wire is suggested?
5. My local code is anywhere from 12" burial if GFI to 24" if not GFI. I pretty much want to bury anything outdoors to 24" regardless. For the 140 feet run from the crawlspace sub to the detached sub, what is the most recommend option... 2 inch conduit with THHN wire or the direct burial wire or direct burial in the conduit?
6. Lastly, is there some type of outdoor rated junction box to use above grade that actually has lugs to gang wires together as opposed to pig tailing with wire nuts?

Thanks in advance and waiting for some good replys!

My answers follow your questions:



1. Is putting a sub-panel in the crawlspace allowed?

Yes. Minimum headroom is to be 6.5 feet, however, there is an exception for a panel that does not exceed 200 amps and is in an existing home, less than 6.5 feet is allowed.


2. If question 1 is OK, can a run another sub-panel off the first for the detached garage?

Yes.


3. If questions 1 and 2 are Ok, would this be MLO type panels with one breaker back at the main only? Or would I need a breaker in the first sub to feed the second sub?

A breaker needs to be in the main panel to protect the feeder to the first subpanel, then a breaker needs to be in the subpanel to protedct the feeder to the next panel.

4. My intended loads for each panel would not exceed probably 40 amps and certainly not close to that in continuous operation. With that in mind, what size wire is suggested?

40 amp total? Hot tubs that I am familiar with need 50 amp alone, plus you mention outdoor lighting, then the garage along with more outdoor lighting and a pump. Based on your details, I don't think 40 amp is sufficient.


5. My local code is anywhere from 12" burial if GFI to 24" if not GFI. I pretty much want to bury anything outdoors to 24" regardless. For the 140 feet run from the crawlspace sub to the detached sub, what is the most recommend option... 2 inch conduit with THHN wire or the direct burial wire or direct burial in the conduit?

The 12 inch deep rule is limited to 120 volt 20 amp GFI protected.

18 inch deep is allowed for conduit

24 inch deep is required for direct burial cable.

6. Lastly, is there some type of outdoor rated junction box to use above grade that actually has lugs to gang wires together as opposed to pig tailing with wire nuts?

No.

6. I was just looking into this briefly and I forget the manufacturer. There is available a splice kit that allows many wires to enter from the same side. Each wire has an available clamp onto an insulated bar.

Some applications of the larger sizes are transformer vaults and underground splice kits without a box. Smaller sizes are used for low-voltage sprinkler lines.

This pruduct from Burndy Burndy Products BIBS4-3 Multiple Wire Terminal, Clear - Grounding and Wiring Accessories @ AltE is available for more than 3 taps. Probably up to 12 or so.