No Grounding Rod for Office Bldg?

[qdvuu]

The facilities mgr of my office bldg and I were talking and he realized that he's never seen a grounding rod for it, so we went for a walk around it to take a look and didn't see one. The ground surrounding the bldg is mainly dirt with some shrubs and mulch with some concrete sidewalks at the doorways, so maybe the rod is below grade.

Bldg specs:
- 42,000 sq ft
- 2 story
- Concrete slab floor
- Built in mid-1980s
- Located in Silicon Valley CA area
- Designed and always used as a high tech office building to house mainly programmers and a handful of electronics technicians
- Houses a data center of approx 2000 sq ft with approx 50 racks
- Has an external diesel generator with an indoors automatic transfer switch in an electrical room.

Is the lack of a visible (above grade) grounding rod normal for this kind of building?

Thanks!

 

[bmwpowere36m3]

Ufer

 

[green.bubbly]

Ufer

That is how my metal building home is grounded.

 

[Slackerzinc]

Definitely Ufer. Best way to ground

 

[tfi racing]

The facilities mgr of my office bldg and I were talking and he realized that he's never seen a grounding rod for it, so we went for a walk around it to take a look and didn't see one. The ground surrounding the bldg is mainly dirt with some shrubs and mulch with some concrete sidewalks at the doorways, so maybe the rod is below grade.

Bldg specs:
- 42,000 sq ft
- 2 story
- Concrete slab floor
- Built in mid-1980s
- Located in Silicon Valley CA area
- Designed and always used as a high tech office building to house mainly programmers and a handful of electronics technicians
- Houses a data center of approx 2000 sq ft with approx 50 racks
- Has an external diesel generator with an indoors automatic transfer switch in an electrical room.

Is the lack of a visible (above grade) grounding rod normal for this kind of building?

Thanks!

So why didn't you two geniuses just pull out the as built drawings for the building, have a look at them,look at what is there now, then determine whether further investigation was necessary? Probably more answers there than a bunch of guesses from keyboard jockeys that have never been to your building,city,state or even your country...

 

[fatfillup]

So why didn't you two geniuses just pull out the as built drawings for the building, have a look at them,look at what is there now, then determine whether further investigation was necessary? Probably more answers there than a bunch of guesses from keyboard jockeys that have never been to your building,city,state or even your country...

What a sweetheart! Having a challenging day?

 

[mike93lx]

You are concerned that a 42k sq ft building didn't have a ground rod because you walked around outside and didn't see one?

I want a job where I can do stuff like this.

 

[Showkey]

It is interesting the fascination with ground rods or grounding system in the GJ. Any legit building was built and and inspected several times during the process.

 

[steel 35]

What will you get done next week?

 

[Dragfluid]

It appears that several folks haven't had their morning coffee yet.

 

[coljar]

Come on guys, that's what we're all here for. He asked a question about something he's not familiar with. Let's not beat him down. The buildings at the plant have the ufer grounding coming up out of the floor next to and attaching to the vertical "I" beam structure. In an office building like you described, you should see the wire piped out of the concrete in a electrical/utility room. It's easier to spot in unfinished rooms. If the wire is coated, it will be green.

 

[Stuart in MN]

Is the lack of a visible (above grade) grounding rod normal for this kind of building?

Yes, it's entirely possible. The ground rod (rods) and ground wire may be covered up so you can't see them, or as others have suggested the building may use an Ufer ground, where the ground wire is connected to rebar in the building footing.

Find the main service disconnect in the electrical room, and trace the ground wire from there to see where it goes.

 

[16again]

Funny that this question comes up now. We are having lightening protection "upgrades" this past week. Men came and put in a few new grounding rods. Had I not seen where they installed them, I would never know. They removed a section of grass and pounded them down a few inches below the surface. They placed the section of grass perfectly back in place.

 

[johnnyradiant]

I've been in a couple legit multi inspected buildings to encounter life threatening electrical issues that leaves one questioning why, let alone what the electrical contractor was thinking in doing what he did, and why was the inspector soooo lazy to not look and see. Just 'cause it was inspected doesn't always mean things are good to go. There are no doubt countless stories in every field in every region about cut corners with the size of missing corners likely quite surprising in some cases.

 

[toplessHO]

Ive found ground wires just stuck in the ground,no rod attached.
I guess they meant to come back and finish..... but didnt.Doing a lot of Telco work,its grounded 3 ways to Sunday.Ive seen lightning do some pretty awful things. Its usually speced in those buildings to get it down to 2 ohms or less.

 

[dmdc411]

I was the maintenance tech at large warehouse facility. Responsible for maintaining mostly the equipment, then facilities as able. I did run the fire pump for sprinklers on a monthly preventive maintenance. Right next to the pump, was a 12 inch water main. The ground wiring attached to rod in the floor, then the water main, and daisy chained over to the main power panel. Building was built in 2007.

Sent from my SM-G970U using Tapatalk

 

[Higgins]

Large commercial buildings will have a ground plate in or near the mail power room. There could also be a cable that goes to a stud on the main water pipe as it comes into the building. Even if it is PVC, that section of pipe has a metal sleeve inside of it!

AL

 

[tab2]

We built a lab for an electrical testing company that wanted 1 ohm to ground; I believe normal is about 25. We hired a company to design it and they spec’ed (14) 40 feet grounding rods 40 feet apart in conductive clay that were drilled by a well rig after they tested the conductivity of the soil. We dug up the entire lot for it since they were all connected by bare copper 18” below grade. It went under the new parking lot and has a few man hole covers for inspection ports. We didn’t get 1 ohm, but they were fine with less than 3.

It also bonded to the water service, Ufer and building steel. And the building steel is connected to the Ufer with anchor bolts. Picture of equipment going in attached.

Moral of the story, if you don’t know about it, you’ll never find it and it has a better ground than everything but a cell tower.

 

[wyliesdiesels]

It is interesting the fascination with ground rods or grounding system in the GJ. Any legit building was built and inspected several times during the process.

HA! not so fast. Inspectors miss **** all the time.

Ive seen all kinds of messed up electrical that was "inspected".

Worked on a 2yr old mcdonalds doing an electrical inspection for NCR. discovered that the 2/0 cu wire GEC from the UFER, coming out of the concrete inside the MDP, was not only NOT connected to the neutral bus, but also half the strands were knicked right at the concrete.

Mind you the electrical inspector signed off on the city inspected panel tag....

I've been in a couple legit multi inspected buildings to encounter life threatening electrical issues that leaves one questioning why, let alone what the electrical contractor was thinking in doing what he did, and why was the inspector soooo lazy to not look and see. Just 'cause it was inspected doesn't always mean things are good to go. There are no doubt countless stories in every field in every region about cut corners with the size of missing corners likely quite surprising in some cases.

:this:

Large commercial buildings will have a ground plate in or near the mail power room. There could also be a cable that goes to a stud on the main water pipe as it comes into the building. Even if it is PVC, that section of pipe has a metal sleeve inside of it!

AL

perhaps theyre more common back east but plates arent used out here.

We built a lab for an electrical testing company that wanted 1 ohm to ground; I believe normal is about 25. We hired a company to design it and they spec’ed (14) 40 feet grounding rods 40 feet apart in conductive clay that were drilled by a well rig after they tested the conductivity of the soil. We dug up the entire lot for it since they were all connected by bare copper 18” below grade. It went under the new parking lot and has a few man hole covers for inspection ports. We didn’t get 1 ohm, but they were fine with less than 3.

It also bonded to the water service, Ufer and building steel. And the building steel is connected to the Ufer with anchor bolts. Picture of equipment going in attached.

Moral of the story, if you don’t know about it, you’ll never find it and it has a better ground than everything but a cell tower.

nope. 25ohms is simply the threshold where code requires a second rod. Most dont have the equipment to test for this so they simply just pound a second rod to meet the code requirement. And pounding a second rod doesnt even mean it will be less than 25ohms either....

 

[GTO]

Come on guys, that's what we're all here for. He asked a question about something he's not familiar with. Let's not beat him down. The buildings at the plant have the ufer grounding coming up out of the floor next to and attaching to the vertical "I" beam structure. In an office building like you described, you should see the wire piped out of the concrete in a electrical/utility room. It's easier to spot in unfinished rooms. If the wire is coated, it will be green.

Thanks for posting this.
I find, that if I can't contribute something worthwhile to a thread....move on.

 

[alfredeneuman]

We built a large 2 story BMW dealership adjoining the KNX-AM transmission tower's property.
The entire building was surrounded with a ring of 2/0 copper, ground rods every 10' and pigtails from the ring every 5' cadwelded to the building steel.
It was buried so you would never know it. Just because you can't see it doesn't mean it's not there