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flyboy771
04-22-2007, 08:59 PM
This question has more to do with the "Home Shop" part. I have 10x14 shed/shop in the back yard that I'll be adding electrical, water, compressed air, and ethernet to it by means of buried lines from the house. The problem is, I'm not sure the best way to do that.

My initial inclination is to use 1/2" copper pipe for both the air and water, and then running the two #6 wires and two CAT-6 cables in their own PVC conduit. I'm not entirely comfortable directly burying copper pipe in the ground, and I'm wondering, would it be best to use PVC instead of copper for the air and water, or can the copper be painted or otherwise coated/wrapped/protected so that it can then be buried?

Does anyone have success/failure stories regarding this kind of setup?

Todd Tolhurst
04-22-2007, 09:05 PM
Copper pipe is fine for burial, but use type K, not the light stuff.

Don't put the CAT-6 in the same conduit with the power.

MTNGUN
04-22-2007, 09:06 PM
I can't imagine why you'd have a problem with buried copper lines, at least, not for 50 years or so. Before plastics caught on, most water service entrances were copper.

I recently started fooling around with pex, and if had to do my shop over again, I'd go pex all the way. You do have to buy at least one crimping tool, around $100, and fittings are hard to find in a small town (but can be ordered). However, it goes really fast and easy.

Wareagle
04-22-2007, 09:10 PM
For the water, PVC would be the way to go. Your air could be ran with PVC underground as well, but I would use schedule 80 pipe for that. Once above the surface, I would convert it to copper, stainless, or thick walled pipe for safety. We had a PVC air line blow up a few years back, and it was a pretty scary experience. Lots of high velocity plastic shards going everywhere, and enough force to penetrate the skin of the building! :eek:

Your electrical and phone/data each need to be in their own conduits. You are asking for trouble if you put them together in one conduit.

flyboy771
04-22-2007, 09:17 PM
Yes, I meant that the data and power cables would be separated, I just didn't say it clearly. Networking is one thing I've done a lot of, just never outdoors.

PVC for everything would certainly be convenient. Thanks for the quick replies.

J. Tranter
04-22-2007, 09:26 PM
For the water and the air you can use 3/4 to 1 in. rolled copper. This keeps you from needing to make any connections under ground. You could also use a poly pipe thats what alot of the plumbers are using now. All you have to do is just roll it out also.
For the electical and cat six they have a grey pvc designed for burying.

flyboy771
04-22-2007, 09:28 PM
I don't mind the underground connections, I have to go almost 50ft, so any one-piece solution would be...unwieldy at best. I'll take a fresh look tomorrow and see what seems reasonable.

Alguy
04-22-2007, 10:22 PM
You might consider laying a 1 inch plastic irrigation line in the ditch when it is open, cap both ends above ground and you will have a run for what ever you wish to add later, i put cable tv and phone lines in mine, that was long after the electric was buried

flyboy771
04-22-2007, 10:54 PM
Good idea, though for the life of me I can't think of anything I'd want to add later. The plan so far is two #6-4 electrical wires (anything you CAN'T run off of that?), two CAT-6 ethernet, compressed air, and water... I suppose I could also run a piece of coax, but what for? Where I live (Orem, UT), there is (or will be soon) fiber optic service covering internet, phone, and TV...and all that will be deliverable over ethernet.

I suppose it couldn't possibly hurt to throw in a strand or two of CAT-3 phone wire I already have laying around. But heck, PVC is darn near free, compared to what I'll be spending to rent a trencher and all the support hardware for the electrical service. Might as well! Sure beats digging up the yard twice or doing something ugly above ground.

scott96088
04-22-2007, 11:00 PM
Good idea, though for the life of me I can't think of anything I'd want to add later. The plan so far is two #6-4 electrical wires (anything you CAN'T run off of that?), .

I would run 3 #4 plus ground total of 4 wires. The power company here wants the ground in sub panels to come from main panel and you need a neutral wire so you can have 220 service for a welder or mill.


Scott

RollaJohn
04-22-2007, 11:19 PM
I would run 3 #4 plus ground total of 4 wires. The power company here wants the ground in sub panels to come from main panel and you need a neutral wire so you can have 220 service for a welder or mill.


Scott

That grounding method is a requirement of the National Electrical Code.

Ron Horton
04-22-2007, 11:54 PM
Greetings everybody--
When I built my shop 3 years ago, I used 3/4" pvc for the air inside the shop-- It's rated 350 PSI, and I only use 150#--
This is the 3rd shop we've used PVC for air, and never had a problem-- One thing you may wish to consider is that with a run of 50+ ft, I'd run at least a 1 inch line for your air-- Your friction loss in 1/2" would be so great, you will not be happy with your air supply as you'd never have enough air--
Best regards, Ron


I know I just had it a minute ago--

dalesvp
04-23-2007, 05:04 AM
Put in an extra fish line before burial might be a good move. If you need to thread something later you're all set.

JCHannum
04-23-2007, 08:05 AM
PVC pipe is not suitable for compressed air service. There are some plastics that are suitable that have been developed recently, but standard Sch 40 & 80 PVC intended for water service should not be used.

http://www.osha.gov/dts/hib/hib_data/hib19880520.html

http://www.lni.wa.gov/Safety/Basics/HazAlerts/902.asp

charlie coghill
04-23-2007, 08:15 PM
If I might add to this thread. Mark all of your lines/pipes with some servayors tape an make a note of what is what and keep the note some place safe.
You never know what you will want to do in the future and having the pipes marked will be use full.

Where I once worked a co-worker drilled into an 480 volt under ground conduit.
Proper cacutions has been used just in case and that turned out to be good. This was in an oil refinery with many pipes being under ground with some being oil, water, gas, and electricty. Prints had either not been drawn out or the drawings had been lost.

wirewrkr
04-23-2007, 11:02 PM
My thanks to MR. HANNUM on the posting of the OSHA warnings concerning PVC pipe for air lines. I was just about to plum my shop with the stuff for air distribution, but perhaps now I'll compare the correct ABS plastics against the copper.
I originally was going to use copper but the fairly recent boom in price had caused me to look at plastic instead. Good timing on this thread, Never even heard of the ABS pipe. Any one know what color it is?
Robert

ckelloug
04-25-2007, 12:00 AM
I have a 1999 NEC companion Handbook to the electrical code from the same people who publish the NEC and they say there is some disagreement as to whether separate buildings fed from the same service should be grounded to the same ground rod or separate ones. From what I've read, it's a matter of interpretation of the code by the local building inspector.

Also, when running power wires, make sure not to run aluminum and copper in the same electrical conduit. NEC forbids it but only due the fact that some idiot electrician could bugger the conduit fill calculation on that basis. I got dinged by my local building inspector for that one although since the copper was a ground wire, he said he would overlook it as it in no way compromised safety.

From 2002 NEC table 310.15B for copper wire used as service entrance wiring:

#4 = 100A
#3 = 110A
#2 = 125A
#1 = 150A
#1/0 =175A
#2/0 =200A

One other thing to be wary of is grounding. Code says that grounding conductors need not be bigger than the largest service conductor. It also says that the wire can't be smaller than those listed in table 250.66. What nobody tells you is electrical service manufacturers serve contractors and that they build service entry equpment that won't fit grounds bigger than those in table 250.66.

From 2002 NEC table 250.66

service #2 Cu or smaller ground=#8
service #1 or 1/0 Cu ground= #6
service #2/0 or 3/0 ground= #4

On a 200 amp service box with 2/0 wire, the ground lug won't likely take a bigger wire than #4 as that is the size of the aluminum wire that would meet the grounding criteria. On a 100Amp box, the ground lug is likely sized only for number 6 wire. . . I had to rework this when I tried to run a 2/0 ground for 200A my service a few years back. . .

Finally, NEC 230.50 A states that the only PVC Non-Metallic Conduit that is acceptable is Schedule 80.

Hope this helps.

Mcgyver
04-25-2007, 07:23 AM
My thanks to MR. HANNUM on the posting of the OSHA warnings concerning PVC pipe for air lines. I was just about to plum my shop with the stuff for air distribution, but perhaps now I'll compare the correct ABS plastics against the copper.
I originally was going to use copper but the fairly recent boom in price had caused me to look at plastic instead. Good timing on this thread, Never even heard of the ABS pipe. Any one know what color it is?
Robert

glad you dodged that bullet, I must admit every time this comes up I'm amazed at how many are unaware of not using pvc for air, then again we all have to learn something for the first time so good for JC for posting it. ABS is the black rigid pipe commonly used for drains in single family res construction; that and potato guns. extremely common. copper's gone up, but the overall ease still makes it the best choice imo

ptjw7uk
04-25-2007, 10:59 AM
The best plastic pipe to use for air is nylon, this is what we used in the laboratory to carry all gases except acetylene which I think was iron.
Peter

Iceman Motorsports
04-25-2007, 02:35 PM
I don't think there is such a thing as good plastic to use for air line. Think high volume air usage air tool, gasoline vapors in shop, and static electricity. Happened in a aircraft repair facility, boom! I'll never use it.

oldtiffie
05-14-2007, 12:51 PM
Deleted/edited-out

yf
05-15-2007, 03:48 AM
About 20 years ago I bored a tunnel from the house to the garage (about 12') and put in 4" PVC pipe and ran all the electric phone air lines in it.

Any additions are easy as there is plenty of room left.

Electric was run in galvanized conduit run in the PVC.
I ran 100 amp single phase 220V in 1.25" conduit.
At the time I was leaning towards 6" PVC, but now I see that 4" is plenty big.

Your Old Dog
05-15-2007, 06:01 AM
A few more observations.

In New York they want ground wire in the shop separate from the house when doing a sub-panel. I had to buy a cheap plastic insulator for the circuit panel to accomplish this.

And when I queried the gas company about putting in copper lines in for nat gas they told me it was allowed in our community because we had low sulfur content in the earth. They still said the trench had to be lined with sand, the pipe laid in and then covered with sand. I never went through with project due to the cost. Instead, I started raising these little beetles, sent them all to Canada and now use a wood burning stove :D