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Monday, August 25, 2003
Running Electrical Conduit

The barn requires good electrical service, of course.  Several weeks earlier, before any of the barn work had actually gotten underway, I had consulted with an electrical that I use from time to time about what would be required to get power out to the barn, and the best way to go about it.  He came over and chatted with me for a time, and we worked out a plan.  I planned to do most of the electrical work myself, but wanted a professional to deal with the main feed and panel, especially since it involved reworking the main service panel in the house.

The distance between the closest corner of the barn and the house was about 115', including about 15' of run directly beneath the deck on the back of the house.  Connecting the new cable run to the barn with the house service would require some fiddling, as access from the outside to where the panel is is a little interesting because of a 14' house addition that was added sometime in the past.

In any event, the plan we came up with involved installing a new master panel in the house, and moving the existing house panel out to the barn for the service there.  To run the cable, I was to install PVC electrical conduit underground between the house and barn.

Once the new slab was poured and in place, I could install the conduit at almost any time.  I had to wait for the slab, obviously, so that I knew exactly where to run the conduit.  For ease and convenience, I chose the front right corner (near the entry door) for my eventual panel location, and decided to run the conduit to that location.

Even though the trench required for electrical conduit  only needed to be 12" or 16" below the surface (unlike the 48" required for plumbing--which I am not installing to the barn), the distance involved was too great to dig by hand.  I decided to rent a trencher, usually referred to as a Ditch Witch (for a common name brand).

It was kind of amusing, actually.  The rental place I use is 20 or 25 minutes away, usually.  By the time I drove there, waited for the machine, and returned, over an hour had elapsed since I had placed a phone call to inquire about renting the machine.  I arrived back at the house and unloaded the huge Ditch Witch.  Driving one of these things is interesting; they steer with the rear wheels (there is only one front wheel to steady the tool), so turning involves a sort of crab walk.  This takes some getting used to.

It was anticlimactic, really.  In short order, I had the machine loaded back on the trailer, and went to return it--another 20 minute trip.  $63.60 later (despite the shortness of time I actually used the tool, I felt this was money well spent), I was done, and headed to the nearby  warehouse store for some electrical conduit.  I picked up 12, 10' sections of 2" conduit (for the main cable), and 24, 10' sections of 1" conduit (for two runs for phone, cable, Internet, or future additions), along with some elbow fittings and a new, longer electrician's snake that I'd need to pull wires through.  I also found some polypropylene messenger line designed for pulling wires, so I picked some up so I could run some through each conduit for ready use in any future addition later.

Now, I had the best part left to complete:  digging a trench under the deck.  The distance from the edge to the side of the house where I wanted to stub up the conduit was about 18', and there was not standing headroom beneath the deck.  Fortunately, though, it is about 4-5' off the ground, so there was adequate room to work--on my knees.

The ground beneath the deck was happily sandy and quite loose, so digging by hand wasn't bad.  I used a garden trowel to dig, along with my hands for scooping out loose dirt once it was freed by the trowel.  After some time (I don't know how long it took--not too bad), the trench was complete, and I finished the three sections of conduit, cutting the final pieces to length as needed and adding stubs at the house end like the ones at the barn end.

When I was sure all the joints were complete, I ran an electrician's snake through one of the pieces of 1" conduit to ensure that it would pass through unimpeded the whole way.  It did, meaning that I would be able to pull wires through as necessary later, so I began burying the conduit.  Using a metal rake, I pulled some of the piled dirt into the trench and tamped it down with the rake and my foot as necessary.  This was tiring work, much harder than any other aspect of the job.  There was excess dirt, as some had been displaced by the three lengths of conduit, so I piled the excess here and there as necessary for later removal.

After a few weeks' delay waiting for the barn construction to progress to a point where wiring could be installed, a flurry of activity over a few days saw the installation of most of the wiring inside the barn, as well as a new  panel and main electrical feed out from the house.

During two evenings earlier in the week, I had installed the myriad plastic electrical boxes needed for the many outlets, switches, and ceiling fixtures that were to be installed in the barn shop.  Following a schematic that I had drawn up, I installed over 50 boxes in the walls and ceilings.

With that preparatory work complete, I enlisted the help of my friend Nathan to pull wires and complete the electrical rough-in.  Two sets of hands make for quicker work than one, and  the two of us managed to accomplish much--but not all--of the wiring in one productive day.  With a right-angle drill, we drilled holes through the studs to accommodate the wiring as needed, and pulled the 14/2 Romex cable through to each box as called for in my schematic.  Because outlets are cheap, I spec'd one approximately every six feet around the perimeter, with several extras here and there as seemed appropriate.  In addition, the ceiling features outlets for up to 25 ceiling fixtures (fluorescent shop lights) and three ceiling fans.  In a solid day of work between the two of us, we managed to rough in all of the wall outlets (which I mounted 42" off the floor--the same as the light switches--for ease of access), run bulk cable for two of the five banks of ceiling fixtures, and for several other applications.  

The next day, working alone, I worked on various aspects of the wiring without clear direction, as I needed some materials but couldn't really leave because I had an electrician on site pulling the main feed cable to the barn and reworking the main house service panel.  The plan  was to remove the older panel from the house and install the shell in the barn (it's a 20-circuit panel).  To better suit the house's needs, I had them install a new, larger panel in the house, so of course that required shutting down the power for much of the day.  

With the power out (though I could plug into Bob's generator as needed), I didn't end up getting that much done in the wiring, though I did install 10 ceiling outlets  that had been rough-wired the day before, and took care of some loose ends (no pun intended) by installing an outdoor outlet box on the south wall of the barn, where the 12' wide boat pad is located.

Much of the morning was spent setting up some pipe staging that Bob had offered to bring down--he needed it for a little later in the project in order to strap the bottoms of the trusses, but offered its use to me for completing the wiring.  Setting up the two, five-foot sections was easy enough, but then it required a platform on top.  I chose three of my old homemade staging planks (a pair of 8'  2x4s on edge with plywood screwed to the tops) and heaved them up on top of the staging.  Then, I had to brace things in place to prevent the staging from racking, so I screwed more 2x4s to the bottoms of my three evenly-spaced planks.  Finally, I laid a sheet of 1/2" plywood over the whole arrangement and screwed it down.  Success!  The staging platform ended up about 12' above the floor, between the planks I had laid on top and the large rolling casters on the bottom.  The casters were the key to the whole setup:  the staging could now be rolled around whilst perched atop, making it extremely useful.

I couldn't imagine having done the job without the rolling staging.  Oh, it would have gotten done, but it sure would have been less convenient, and more time-consuming.  Having the right tool for the job is simply priceless.

Unfortunately, Bob and I spent a good part of the day chatting, slowing up both of our respective work schedules.  Oh well...

The next day, Saturday, I attacked the wiring with a vengeance.  Early in the morning I purchased several more rolls of wire that I needed, and some other things, and got to work at once.  My plan was to complete the raw wiring runs, so as to be ready to wire the breaker panel the next day.  I worked alone on the wiring all day, beginning with running 5 lengths of 14/3 cable for the three-way light switches I wanted for the overhead lighting.  I thought it would be useful to have the lights controllable from either the man door on the north wall, or the smaller rolling door on the south wall.  Great idea on paper...but in practice it required 5 runs of this heavy, kinky, unwieldy cable, each one ending up using about 70' of cable.  It took me most of the morning to complete the job.  With that done, I moved on to running a dedicated 20 amp circuit for my table saw, dropping a pair of 20-amp outlets near the electrical panel, and completing the remaining three banks of overhead outlet--15 in all, plus associated wiring and connections.  The overhead outlets will be used to install the shop lighting; the fixtures I chose feature a normal wiring plug and are not hardwired.  

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