Shop Utilities - in wall or on wall?

[nvbigblue]

Greetings!

My building is on it's way and will be going up sometime early next year when I get home. Since I've got plenty of time on my hands here, I've been drawing things up in Sketchup trying to get everything figured out.
My building is an S model arch building and the walls are straight up for about 9 feet. My plan is to line the metal with internal walls using 2X4 framing and 1/2" plywood. The shop is going to be sprayed with foam for insulation, so this will accomplish a couple of things:

1. Keep me from dinging the foam down low.
2. Allow me to mount peg board, etc. on the walls.
3. Prevent sparks from welding or cutting from contacting the foam.

So my question is this:

Should I run my utilities inside the 'sub-wall', like a normal house? Or should I conduit everything externally?

There should only be air, power and networking cables, but I have thought about a dust collection / general vacuum system as well.

The framing will be bolted to the metal prior to spraying foam, and then sheeted with the plywood. There will be some room on top of the walls, but with 3 separate runs, it might get tight with the foam. Or I run them along the length at some height off the floor. The only real benefit I see with using conduit is the ability to add another outlet or air drop a little easier if I needed to at some point. But if I ran things internally, I would save the cost of conduit and the walls would be a little 'cleaner' overall. I have not decided on pipe or something like the rapidair system, but I will NOT be using PVC for the air system.

So.... what are your guys thoughts on this?

NV

 

[CNGsaves]

If you can afford spray foam insulation, then I'd say do all the other systems top-notch as well.

Put all your electrical in-wall with Romex for the routine items like outlets, light switches, etc. For areas where you might want future expansion (ie more switches, power outlet, compressor, welder, hanging ceiling heater, etc) then run conduit in the "wall" and rough in the box. Include a pull string so that you've planned ahead.

For airline system, go with Lifetime quality (black pipe steel or copper) and PLAN it all out. Most all airline systems are surface mounted up around the perimeter of shop, with drops where needed. There is excellent thread by Stouty that you definitely need to read.
http://www.garagejournal.com/forum/showthread.php?t=214394

Plan out where you will have benches, tool boxes, storage, etc. Put your wall outlets at 49" off ground so they clear benchtops.

So the moral of story is Planning, Planning, PLANNING !!

Enjoy the planning process . . . this is YOUR best chance to make it right.

 

[spongerich]

I'm no expert, but I'd think that the cost of the conduit for external wiring would add up pretty quickly. I'd probably run mine in the wall and use the money saved to install "too many" receptacles and a bunch of extra junction boxes. If you end up needing to add circuits later, you could always run them outside the wall.

 

[fourjeepin]

Another vote for in the wall. Conduit doesn't look as good and is probably more expensive.

 

[p_mori7]

I will be doing "on-the-wall".

I like the look of metal boxes & cover plates.

I will be using the metal coil wrapped wiring.

I will be securing it to the wall with metal clips.

 

[Nowater]

Where I am, no romex or emt (thinwall) in a garage by code. I ran pvc conduit with a ground wire and surface mounted all my boxes and switches --easy to move that way despite all the "planning" before hand! Main runs are at the top of the wall and I made drops down to where I wanted a receptacle. I think it adds to an industrial look, and I can pull 220 volts where I want.

PVC can be bent using a heat gun and some patience. One can buy 45 and 90 degree ells. Glue goes quick and easy as long as you put the cap back on the can. No fish tape? Ball up a small piece of paper and tie a string on it. **** it through the conduit with your shop vac. Pull in a larger string to pull the wires. Pull in a spare or two!

 

[arturo7]

in-wall + romex

easy squeazy

 

[crewchief888]

on wall gets my vote,
heres my reasoning...

with a new structure, i'd rather have it insulated and closed in first, extremes of temp could be tolerated easier, while working on electrical and air lines.

i could "tolerate" 1 light bulb and outlet trying to work.
freezing my *** off in my garage isnt my idea of "fun", altho i do it every winter.

i had had planned on insulating and closing in my garage, adding lighting, air lines and a LOT more lights. however once everything got moved into the garage, i found out it wasnt gonna happen.

 

[shawnspeed]

I would do external...for a couple reasons...one you mentioned spray foam...once it is in , you are locked in to doing changes external...upgrading would be hard. I have had several shops in the last 20 odd years, and also worked for several people that moved there shop...more than once, and typically all that external wiring that was added to install machinery was removed & reused in the new shop...yes not all of it always was utilized, but the basics were always there. Conduit and THNN is a breeze to work with once you are used to it , and I have not found an inspector yet that turned his nose up at it...Air same thing , Black pipe, and make sure you plan your runs, put in moisture traps on the drops, and isolate the Pipe from the compressor with a 1' section of 3/4" hydraulic hose....Dust collection, be sure to separate the metal sander from any of the wood stuff...just saying ...it is also much easier to add or change any exposed system to one buried in a wall...