Electrical for Tiny House on Wheels

I am designing a Tiny House On Wheels (THOW) that I am planning to build and am wondering what the electrical requirements are. Mainly, at this point I am trying to decide where I can put the electric panel and clearances it needs to have. I am treating this structure as a residence, not an RV, hoping that The Tiny House appendix of the IRC will be adopted by the time I'm ready to build. And, of course, I will be hiring a professional electrician to help me with this eventually, but I am trying to be on top of things as much as possible before then and have my design mostly done. I have some plans including a lighting plan and a rough draft of the electrical panel that you can check out here if you want and see my SketchUp model here.

 

Are you planning to move this from place to place or leave it permanently in one spot?

If you are leaving it in one spot, your panel and clearance should be the same as that of a mobile home.

If you are going to move it from place to place, you will need to treat the connections like an RV.



I'm not 100% certain but I believe you'll have to remove the wheels, set it on blocks and anchor it to the ground, before the county will issue a occupancy permit.

 

The NEC panel clearances are 30" side-to-side and 36" out from the face of the panel. The panel does not need to be centered in the 30". Making the panel accessible from the outside via a removable access panel may be the only way to meet the required clearance.

There is no provision in the NEC for what is essentially an RV as it is not a "building". Mobile homes are even a gray area when it comes to code. The manufacturers follow a similar code for manufactured housing in the initial construction, but then they are held to the NEC code once they are installed on the lot and you connect the service.

 

Ideally, I would be anchoring it to the ground and doing whatever else is needed to have it qualify as a residence under the tiny house appendix of the IRC. My understanding is that mobile homes (manufactured home) are legally different entities. They have size restrictions and cannot be built by DIYers, so if a mobile home (manufactured home) uses a different set of codes than residences in determining where the electrical panel can be and its clearances etc., I cannot use them for my Tiny House. I think what I am looking for is where I can put my electric panel, etc. in my tiny house when treated as a residence.

 

Thank you! That is very helpful. Are there any restrictions in the room? I think I read somewhere that it cannot be located in a bathroom, bedroom or closet. I believe this was the same place that said there needs to be a 36" clearance on sides and in the front. Also, is there requirement for distance off the floor?

 

90% of the time where I live main electric panel is mounted outside on a wall of the house. While it isn't as common the further north you go I don't think it is forbidden in most jurisdictions. Mounting it outside would make space considerations around the panel easy to meet.

 

Kitchens and bathrooms are forbidden; some cities or states limit bedrooms, but that is not in the NEC. Closets are OK if it is only a utility closet (no storage allowed), which probably isn't practical in a small house. I would think the only likely candidate inside a small house would be in a hallway or common area. Outside seems like a good option. You could use an exterior panel surface mounted on the outside wall or build a cubby into the exterior wall with a removable access panel that would allow access from the outside.

 

From your plans, your choices for where to place the electric panel are limited. As suggested, you could mount it outside the house, or beside/behind the front door.

 

That information is very helpful!
Thank you very much!

 

I'm assuming it can be recessed in the wall, but can you place something over the panel door like hang coats over it (behind the front door is where I plan to hang coats) or place a picture over it?

 

The panel has to have full access, you can put a cabinet type door over it to dress it up but nothing that restricts access [has to be moved first] no shelves or hangers.

 

You could probably design the height of it such that the coat rack does not obstruct the panel, which in my opinion would be OK but I could see an inspector having a problem with it. You can hang art or some other sort of decorative panel over it.

 

Just asking for personal knowledge. Could the OP mount a cabinet door over it, then place coat hooks on the door facing? To access the panel, he could open the door with any coats.

 

Details are all up to the local inspector's interpretation. The code language does allow for doors to be swung open or closed to meet the required clearances; however it also states that there should be no storage in front of a panel. It's a judgment call. My opinion is that your plan would be OK.

 

I think all your answers were very helpful. Thanks so much for your input.

 

I'll say again outside is a lot simpler IMHO. Do you have reasons why that might not work for you? Here it is directly below the meter so if you plan on having a meter that would make it simpler. You could even use a combo meater/breaker box.