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Just wanted to know what are some key things to remember/start with when Laying out and doing underground work. Seems like things can get overwhelming when all youve got are a set of prints and a dirt field

Whats the order it goes in?

What would you locate first or where would you start?

Just like to have an understanding as an apprentice of the big picture since ive only got about a month/half of UG experience. Sure my shovel game will be put to use again at some point. Never hurts. ;)

Thanks!
 

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Just wanted to know what are some key things to remember/start with when Laying out and doing underground work. Seems like things can get overwhelming when all youve got are a set of prints and a dirt field

Whats the order it goes in?

What would you locate first or where would you start?

Just like to have an understanding as an apprentice of the big picture since ive only got about a month/half of UG experience. Sure my shovel game will be put to use again at some point. Never hurts. ;)

Thanks!
Electricians are not surveyors. Get with the GC. He should be glad that you want his input so that the job goes well and you are off the hook.
 

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What would you locate first or where would you start?
The outside perimeter of the building? There will at least be corner markers. Hopefully a string all the way around.

Generally the plumbers would be in first because they need more depth for their waste lines.

I have only done one large UG job and, although it saved a LOT of time on the rough in, it was also a PITA. You have to measure and lay out string lines for the walls you want to hit and I missed a panel wall by 6" :jester: That killed a half day Saturday :rolleyes:
 

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IMO, we (electricians) need to verify the survey stakes make sense. In other words, if you get the walls of the building marked and strings pulled, pull a tape and make sure it matches the prints.

Put the bigger conduits in 1st. Think through the whole thing, before you put the 1st stick in the ground, you should know how the last one finishes.

Don't trust anyone (especially concrete guys) to watch out for your stuff. Make sure it's secure and won't move around during the pour (concrete).
 

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You have to measure and lay out string lines for the walls you want to hit and I missed a panel wall by 6" :jester: That killed a half day Saturday :rolleyes:
I roughed in an gas station for a prefabbed building. The building super showed me the survey stakes and told me what they represented. Well, we miss-communicated and the string I worked to was 3" off from the opening in the floor of the prefabbed building. I was lucky in that I could bend the conduits towards the floor opening then straighten them back up after the building was set.

Of course, the super denied he told me what I heard him tell me. I blame myself for not pulling all 4 strings for building walls and checking the layout myself. If I had, I would have discovered the discrepancy.
 
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Check the job specs. to see if they require rigid sweeps up through the crete.
And then get a letter from the EE to remove that stupidity :laughing:


I got a letter to remove the 18" deep specified requirement and ended up paying a small price when the saw cutters chopped thru a few 3/4" runs :rolleyes: The UG really should be down over 6" to avoid future issues with saw cuts.
 

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for most standalone (simple) buildings
1) decide whether to get in before footings, or if you need sleeves and install before the footing guys get going
2) service(s), outside tranny/em gen, outside feeders (parking lights, whatever) /coordinating with other trades, poco, and site utility guys so your stuff doesn't get fooked, buried wall sleeves if any
3) slab work for lowest level and risers if any are under the lowest slab
 

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Just wanted to know what are some key things to remember/start with when Laying out and doing underground work. Seems like things can get overwhelming when all youve got are a set of prints and a dirt field

Whats the order it goes in?

What would you locate first or where would you start?

Just like to have an understanding as an apprentice of the big picture since ive only got about a month/half of UG experience. Sure my shovel game will be put to use again at some point. Never hurts. ;)

Thanks!
Have all of you conduit runs drawn on your own drawing. Do this before you start. And don't just show arrows pointing to where this 2" goes. Draw them out from point A to point B with sizes tagged to the lines. Do a take-off of all material, and have them on the job.
The GC will determine "when" these goes in. Concrete takes precedent over EVERYTHING in the GC's mind.
When the GC says you can rough-in southeast corner of the parking lot tomorrow, then he tells you you can rough-in the south corner of the parking lot Thursday, that means you will have to run to a point, and stop.
Take those plans and color in what was installed where, where they are capped off, and when the work was done.
I hate doing it that way, but you have no choice. This drawing is your only protection of getting covered up, and you resource to protect you when conduits are damaged by others. It's also your documented as-built drawing which you will have to provide later anyway. So do it now!
 

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The biggest major problem I've witnessed with contract drawings is that they don't &
won't let go through a foundation wall or footer with your pipes!

You either have to go under the foundation or you have to stay above
finish floor/grade in what ever manner to get inside.

Digging a hole to get under a foundation can get complicated if not expessive
you have to usually back fill with crush and run or new clean dirt and compact it!

Once the run is out of the building you can stop short of the end run (exact
position) just 20' 30' if you need to! Tape the ends put a stick 2x 4 vertical
in the ground and cover it back up! The stake should also be flagged and spray painted-and of
course out of any traffic path. I've done this several times for various reason, site not ready, area of run
not even ready and under 30' of dirt.

You have to get in line to dig on a site, You also need to get "no cuts" if your
going to be anywhere near the edge of property(period). this can be up to ten feet inside properties edge.

You have get the GC either to stake or survey the final grade so that your work is to the correct depth(period) working to a correct or known grade is parimount!

Hope this helps.
 

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calispark said:
Just wanted to know what are some key things to remember/start with when Laying out and doing underground work. Seems like things can get overwhelming when all youve got are a set of prints and a dirt field Whats the order it goes in? What would you locate first or where would you start? Just like to have an understanding as an apprentice of the big picture since ive only got about a month/half of UG experience. Sure my shovel game will be put to use again at some point. Never hurts. ;) Thanks!
. I'll try to put this in order of importance and sequence . 1) don't waste time guessing where walls and column centers are until the GC / surveyor give you some good bench marks ! This is their job to tell where the building sits . 2) layout for footing sleeves and install before footers get poured 3) as stated before , have your service , feeder , and site ltg. Conduits mapped out on an architectural site plan . 4) get service and feeder conduits in first because they're larger and you want them deeper than the slab 5) smaller branch conduits usually get scratched into the stone , but I prefer them deeper . I've seen too many get cut up because they were too shallow . 6 ) never scale wall or equipment rough ins off of anything but a dimensioned architectural drawing . Scale off an electrical print , and you'll be sorry ! 7) never follow plumbers for wall locations . They're rarely right and a chipping hammer is their best friend , lol ! That being said , it's not hard , but it's all in the layout ! If you run out on a slab with a bunch of conduit , glue , and no real gameplan , it will get ugly .
 
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