Trenching epiphany

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Coppersmith

Coppersmith

Senior Member
Location
Tampa, FL, USA
Occupation
Electrical Contractor
I am not fond of trenching at all. Usually, the trench I need is 20 feet or less so I hand dig, and minimize the work by using IMC conduit which only has to be buried 6" but costs four times as much. This is well worth it IMHO as it saves lots of labor costs and old electrician effort.

I'm doing a job now that requires a 90 ft trench and decided hand trenching 90 ft in this heat would kill me (literally) so I rented a trenching machine. And since the trenching machine can go down 24", I decided to save money and use PVC. Here's where things went horribly wrong. Although the machine can go down 24" and all I needed was 20" it got hung up in spots (a lot of spots actually) and so I spent two hours hand digging to clean up the trench before I could dump the PVC in.

After I have the pipe in the ground and spend another hour measuring to make sure it's buried deep enough and then covering parts of it so it won't float when it rains before the inspection I have the epiphany: If I had just used IMC with the deep trench I would have avoided hours of hand digging to clean up the trench, measuring depth, and covering for rain. And I could have shot for 18" deep and saved a lot of covering work. I could have assembled and dumped the IMC and been done. Plus the machine chopped right through the roots I usually have to cut.

So my new trenching method is rent a small trencher (18" deep max), dump IMC in the trench, cover. Boom! Done! Loving it!

Perhaps this is old news to you guys and gals. If so, feel free to comment on my ignorance or spoil my good mood with facts not in evidence. Before you comment on cutting, threading, and bending, let me say this: threadless compression connectors, factory 45's/90's.
 
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Coppersmith said:
I am not fond of trenching at all. Usually, the trench I need is 20 feet or less so I hand dig, and minimize the work by using IMC conduit which only has to be buried 6" but costs four times as much. This is well worth it IMHO as it saves lots of labor costs and old electrician effort.

I'm doing a job now that requires a 90 ft trench and decided hand trenching 90 ft in this heat would kill me (literally) so I rented a trenching machine. And since the trenching machine can go down 24", I decided to save money and use PVC. Here's where things went horribly wrong. Although the machine can down 24" and all I needed was 20" it got hung up in spots (a lot of spots actually) and so I spent two hours hand digging to clean up the trench before I could dump the PVC in.

After I have the pipe in the ground and spend another hour measuring to make sure it's buried deep enough and then covering parts of it so it won't float when it rains before the inspection I have the epiphany: If I had just used IMC with the deep trench I would have avoided hours of hand digging to clean up the trench, measuring depth, and covering for rain. And I could have shot for 18" deep and saved a lot of covering work. I could have assembled and dumped the IMC and been done. Plus the machine chopped right through the roots I usually have to cut.

So my new trenching method is rent a small trencher (18" deep max), dump IMC in the trench, cover. Boom! Done! Loving it!

Perhaps this is old news to you guys and gals. If so, feel free to comment on my ignorance or spoil my good mood with facts not in evidence. Before you comment on cutting, threading, and bending, let me say this: threadless compression connectors, factory 45's/90's.
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um...... schedule 80 pvc. purple primer. glue. factory 90's.
schedule 80 pvc around here is a direct replacement for GRC.
and you can get schedule 80 pvc couplings as well.

i'm also fond of just gluing it up and then throwing it in the ditch. but i'm lazy.

just a thought....
 
Fulthrotl said:
um...... schedule 80 pvc. purple primer. glue. factory 90's.
schedule 80 pvc around here is a direct replacement for GRC.
and you can get schedule 80 pvc couplings as well.

i'm also fond of just gluing it up and then throwing it in the ditch. but i'm lazy.

just a thought....
Click to expand...

Is that an amendment? Table 300.5 says only rigid and IMC can be buried 6" deep. I would gladly use schedule 80 otherwise.
 
Coppersmith said:
Is that an amendment? Table 300.5 says only rigid and IMC can be buried 6" deep. I would gladly use schedule 80 otherwise.
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well, in the port of long beach, stuff ran exposed must be GRC or Schedule 80 PVC.

so if it's ok exposed.... :? be patient. we have a budding 9 page thread here in the making.
someone else will chime in yay or nay..... my assumption was if they were interchangeable
above ground, they would be interchangeable below ground.
 
Fulthrotl said:
well, in the port of long beach, stuff ran exposed must be GRC or Schedule 80 PVC.

so if it's ok exposed.... :? be patient. we have a budding 9 page thread here in the making.
someone else will chime in yay or nay..... my assumption was if they were interchangeable
above ground, they would be interchangeable below ground.
Click to expand...
IIRC Schedule 80 PVC used to be called Rigid Nonmetallic Conduit, so I can see how it could be allowed.
 
I asked a guy one time who was digging the trench him or me? He said he figured I would do it? OK but I charge $60 an hour whether I'm doing electrical work or digging ditches. And? I don't dig very fast. :happyno:
 
We must be gluttons for punishment here in New England because almost nobody ever runs IMC or RMC for trenches to get around the cover requirements despite having the rockiest soil known to exist. We just dig up the rocks and put in our PVC, though truthfully sometimes pipes aren't buried to code depth. ;)
 
peter d said:
We must be gluttons for punishment here in New England because almost nobody ever runs IMC or RMC for trenches to get around the cover requirements despite having the rockiest soil known to exist. We just dig up the rocks and put in our PVC, though truthfully sometimes pipes aren't buried to code depth. ;)
Click to expand...

Noooooooooo, really?!? :roll:
 
We bought a mini ex two years ago, it paid for itself a year ago.

It's usually already on the trailer or can be loaded in a few minutes and strapped down. I will run it down the road to a job even if the trench is only 20', because it literally takes about 8 minutes to dig, and that's if I'm going slow.

Before we had this, we used to do a lot of hand digging. And by that I mean apprentices and shop help. I think they love the mini more than me.:lol:
 
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