Adding new overhead outlets in garage - conduit required?

Question

I plan to install 3 new GFCI breakers in my electrical panel in my garage, and pull three dedicated runs through storage space above my garage to my woodworking power tools (overhead outlets). I thought this task would be simple: the electrical panel's existing wiring exits up the garage wall behind drywall, and I had assumed that the wiring exits into the storage space above my garage. However, when I looked closely, the storage space above my garage is NOT directly above the electrical panel. I have accepted the fact that I will need to cut out some drywall from around the top of the electrical panel, punch out three knockouts, and route the new wiring at least 4' horizontally (drilling thru several studs) before I can route the wiring upwards and into the space above my garage. THIS is where I need assistance.  The garage wall where the electrical panel resides is an exterior wall. The top plate of this wall is not exposed to the elements, but it is directly beside a rather wide, long roof/soffit ventilation "trough" (which runs all the way around my house). Is this ventilation trough considered "exposure to the elements"??? Is there anything in the NEC 2015 (my town uses the 2015 electrical guidelines) that prohibits me from drilling through the top plate of this exterior garage wall, and running my 12 gauge wiring directly to the desired outlet locations - without using conduit?

The original wiring (1993) that feeds the garage lights, outlets, and garage door openers does NOT use conduit, but that old wiring was installed before the garage drywall was installed, and thus does not follow the path through the exterior wall's top plate. I would prefer to avoid conduit, as the wiring runs are less than 15' each - seems like overkill to run conduit. I'm a do-it-yourselfer, have significant experience with both AC and DC in an industrial environment, but I do not want to fail a home inspection when I move away some day.  I believe in "doing it the right way the first time", but I'm hoping the right way is "conduit not required"! Thanks... John in Dallas

Answer 1

The vent is under the roof and you said you have Sheetrock inside so that would make the location “dry” by code standards. Can you run NMB exposed on a ceiling, actually you can if it is over 8’. Code has no specific height some states allow over 7’. Most inspectors use the height protected by elevation of 8’ as a basis for the 8’.

I would suggest using metal clad type MC it is a little more expensive but exposed it is more common and most consider that first finished compared to nmb or Romex.

Believe me for resale metal clad or MC makes a difference. As someone that has been part of a team that flipped old houses this is one of the “upgrades” we commonly did in garages a 250’ roll 12-2 (3wire) is under 100$ You can get smaller coils but 250’ was usually the best price and a manageable spool (1000’ sucks because of the weight and size and is not much less per foot). The realtor we used said ~10k price increase compared to open wiring of cloth or nmb that is common in my area in the older homes. Note your home would Not be considered older and the nmb on the outside screams DIY and no permits. Conduit or metal clad if installed neat looks much more like a pro job.

Answer 2

Texas does not generally require conduit. When I moved from Chicago ( all conduit) to Houston , I was shocked to see a cobweb of plastic covered wire coming out of the main box in a new home. You get accustomed to it and it apparently does not cause problems. A big labor saver over adding lines in conduit for Chicago. Conduit is not required in TX ( daughter-in-law house in DFW - no conduit). I use conduit whenever outside.