Electrical – How to run conduit from external wall into basement cellar

basementelectricalexterior

Context:
So I have recently had solar panels installed in a historic home and ran the electrical conduit from my roof down into the existing ingress into the ConEd and electrical panels in the front of the townhome. This is just like all the other historical townhouses on my block and in my neighborhood. Unfortunately, landmarks commission rejected the conduit saying it was in the front facade and that my neighbors were grandfathered into their existing conduits in the front and I would not be allowed to add a new one. Thus, they want me to reroute to the back of the house facade. My choice is to either do a community board appeal or figure out how to route it through the back of the building. It's been difficult to get the original solar installers along with construction work during the COVID stoppage so I'm trying to figure out the level of effort to run it through the back and get it inspected again by both the city and the landmarks commission vs going through the rigamarole of appeal.

My question are around my options for getting conduit into the basement from the exterior:

  1. I have a chimney from the roof to the water heaters in the basement with dual "clay-lined tubes" which I recently renovated, relining one with steel and blocking the other off at the basement. Can I re-purpose the unused clay lined chimney and run my metal conduit into the basement and have it be up to code?

  2. I can just create an ingress through the thick brick wall in back, but would I have to pull up the stone flooring in the backyard to dig a trench to get to the basement level and drill a hole below grade to run conduit? Would that cause possible moisture leaks into the basement – it's pretty dry currently and I don't want to introduce a new way for water to get in.

  3. Would I punch through from the ground floor wall above grade and then punch down through the interior floor into the basement? I have finished walls and a finished basement ceiling so that would require a lot of cutting and messing with walls and ceilings and paint and interior work. I do see an existing framed and finished run on the wall for a dryer vent from the basement to the outside which would save me from cutting into the interior floor if I can just open that part of the interior wall. Can I run a conduit alongside a rigid dryer vent in the same wall framed cavity? Would the conduit need to be insulated?

Which of these options seems like the least effort and risk.

Best Answer

The "unused chimney flue as electrical chase" seems like an ideal solution to both "historical appearance issues" and roof to basement access.

I can't see a code issue with that, if done properly.