Estimate time to install conduit

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I have a job were I have to install about 3K feet of 3/4" emt on a roof. This appears to be a fairly easy install. Attached to brick approx 3 feet off of roof, then along rooftop on stand-offs and attached to HVAC units. Can anyone advise how many man-hours to charge per x feet of conduit? Thanks.
 

GUNNING

Senior Member
Land mines

Land mines

Triple material costs. Wire? Brick wall part of owners building or common area or neighborer building?? Are you going to warrant roof after job? Is the site easily accessible and materials stage-able?
 

SBuck

Member
EMT? I would think in Maryland you should use IMC or GRC. When the snow sits on that EMT it will rust though quickly, you will be back in a couple years to replace that conduit.
 

SBuck

Member
I have worked the majority of my electrical career in northern Indiana. Any time EMT is installed outside in short time it will rust through. I have been down to southern Texas and seen all the EMT installed outdoors, which was doing just fine it just would get surface rust after a while.

Different methods for different climates.
 

GUNNING

Senior Member
i agree

i agree

Different methods different places. I have seen PVC exposed running on roofs blackened, wavey, seperated, but installed, inspected and acceptable. Sometimes it is just cost and nothing else. You get what you pay for and lowest bidder gets the job.

Speaking to the perspective of the property owner it's steels too expensive, and we are going the turn a quick profit and flip the property. Can't argue with that if you want the job.
 
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ASK_EDDIE

Member
Location
TEXAS
ARTICLE 358
Electrical Metallic Tubing: Type EMT

358.10 Uses Permitted

(C) Wet Locations. All supports, bolts, straps, screws, and
so forth shall be of corrosion-resistant materials or protected
against corrosion by corrosion-resistant materials
 

tkb

Senior Member
Location
MA
ARTICLE 358
Electrical Metallic Tubing: Type EMT

358.10 Uses Permitted

(C) Wet Locations. All supports, bolts, straps, screws, and
so forth shall be of corrosion-resistant materials or protected
against corrosion by corrosion-resistant materials

Pretty much any straps and hardware you get from the supply house will be plated and meet the code requirement.
You will just have to make sure the fittings are rain-tite.
 

jmellc

Senior Member
Location
Durham, NC
Occupation
Facility Maintenance Tech. Licensed Electrician
I haven't done roof work like that in awhile, but my rough estimate is 200 man hours, max, to install 3,000 feet of EMT. Thinking 2 man crew, 300 feet a day, most days. Sounds like minimal bends, no precision leveling, etc. until you cross the roof. I assume you are using standoffs such as 4x4 lumber? Drilling brick may be quick or slow. I've seen soft brick, easily drilled & harder brick that took a while. Mortar joints sometimes do well, sometimes crumble when drilled.

Probably a day to pull wire, a day to terminate equipment.
 

SBuck

Member
ARTICLE 358
Electrical Metallic Tubing: Type EMT

358.10 Uses Permitted

(C) Wet Locations. All supports, bolts, straps, screws, and
so forth shall be of corrosion-resistant materials or protected
against corrosion by corrosion-resistant materials

Most people on this website should know the code. But the code is a minimum requirement, like I have said before EMT can and probably will last in the south because it will rain and the rain just trickles right off. But in the north the snow will just accumulate on the brackets and EMT, it would be no different than installing EMT under water.

I am not saying people installing EMT outside are wrong. It just does not work well in the snow.
 

jmellc

Senior Member
Location
Durham, NC
Occupation
Facility Maintenance Tech. Licensed Electrician
I've seen outdoor EMT last a long time in some locations, but rust quickly in others. I need to read up again; didn't NEC used to specify that outdoor EMT had to be coated or protected for outdoors, similar to straps, bolts, etc.? I for sure have never seen it do well underground. Never dug up any that hadn't corroded to onionskin. In some cases, sections were gone altogether.

I know for sure it won't last long in areas with some types of fumes. I used to do a lot of work in a plant nearby. Angle iron supports would rust to fragility in less than 2 years if not painted with epoxy. We used all rigid or PVC on that roof. We used painted angle for most of our stands, brackets, etc.
 
EMT as opposed to PVC

EMT as opposed to PVC

I am putting in an alarm system for the HVAC units. The dealer rep suggested EMT as opposed to PVC due to grounding issues. If I used PVC, I would have to put surge protection at each alarm expansion board (28 of them) and run the ground wire back to the head end. It may be a wash due to the higher cost of EMT as opposed to PVC. I always look forward to hearing different suggestions.
 
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