I Think I Conduit

Little did I know that when my mother would read to me the story about the Little Engine That Could, (my favorite bedtime story) she was preparing me for building a double-wall, cordwood house. As I chugged and puffed around the house installing the electric tubing I kept saying to myself “I think I conduit, I think I conduit.”

I chose to use metal conduit (or as it is known in the trade as EMT – Electrical Metal Tubing) because once the cordwood walls are up, there’s no way to replace or repair electrical lines in a cordwood wall. Having the luxury of a double wall, I’m able to run the tubing in between the exterior and interior wall and the receptacles and switch boxes can be attached to any one of the 32 posts that are in place to help stabilize the internal wall. Besides running electrical wire, conduit can be used to run phone lines, TV/audio cable and whatever else your heart desires. Metal also readily adheres to mortar, so the metal conduit and electrical boxes will help tie the walls together.

Using EMT requires a pipe bender and can be challenging at times, especially to a neophyte like myself. I’ve used it a couple of times before to run new circuits to the sun room at our house in Illinois, but pipe bending is an art. (Chicago and most of the surrounding suburbs requires EMT in any new construction.)

Minnesota state code does not require EMT in new residential construction. Romex and rigid nonmetallic tubing is acceptable, but Romex is a one time shot in a cordwood wall. If it ever needs to be replaced, the wall would have to be destroyed to get to it. Nonmetallic plastic tubing is certainly an option, but I like EMT for the protection it provides.
To the left of the conduit, is a template that I used to mark the placement of the electrical boxes.

Another option, which may or may not be code in different areas is a blue flexible, plastic tubing sometimes referred to as “Smurf” tubing. I hadn’t thought of this option until someone brought it to my attention on the forum. Smurf tubing seems rather fragile though and I don’t think it could stand up to the abuse of fishing wire through long lengths of it. You could run the wire through the tubing before the cordwood walls were built, but if you had to replace the wiring somewhere down the line, it could be trouble.

Code requires that electrical receptacles be placed within 6′ of appliances in any given living space and with 4′ of appliances in kitchen areas. So by the end of the week, over 250′ of EMT was installed and over 30 electrical boxes just for the perimeter walls of the house. As with the rest of the house, some of the electrical boxes installed were overkill, but I’d rather have enough feeds for electric, phone and who knows what else before the walls go up and its too late to change things.

All of the conduit runs are incomplete at this time. In other words, the conduit leading away from the outer walls doesn’t terminate at the circuit panel. At this stage of the game, I just wanted to get the outer walls inspected so I can get back to cordwooding! Speaking of which, the electrical inspector is due out this coming Wednesday. He will be out to inspect new circuits to the utility area, bathroom area, hot water tank and of course, to give his blessing on the cordwood walls.

This coming week will find me putting my plumbing hat back on as I install the hot water tank and plumb in the vanity in the bathroom, the shower as well as the washtub in the utility area. I should be in “hot water” by the end of the week and maybe solar hot water to boot.

This week’s photo comes to us from a Mrs. Deborah Thomson of Cary, Illinois. She writes “I found this horrible beast in our bird feeder last weekend.” Well Mrs. Thomson, I’d be more concerned about those mutant carrots you’ve got growing in your yard.