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Ufer for "lightning" protection

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Tizzle

New User
Location
Wet Coast
Occupation
Spreadsheet Wrangler
Hi all,

I have a bit of an oddball set of questions and am hoping someone here could lend some guidance.

Short story: A property out in the boonies has a 15KV line going very close to the rooflines of several buildings. This is in a heavily forested area, and there are a ton of trees that could very easily take this line down. The buildings that this line runs close to are all getting major renovations, and among other things, will be getting metal roofs and solar panels.

Removing or burying the line is not practical, and it’s really a question of when (not if) a tree goes down and takes the line down with it. If the line goes down, given its location, it’s likely it’s going to come into contact with one of those roofs. So, the question has come up regarding what can be done to mitigate damage if it does hit a roof. Also, there's a 3amp fuse lower down in the property. What has been proposed is to essentially run the equivalent of a lightning protection grid along the leading edges of the roofs that could come into contact, and then dump all of those into an overbuilt Ufer run into a soon to be poured retaining wall that runs between the buildings. Then tie the Ufer back to the main ground where the 400-amp service enters the first building (other buildings are all on sub panels of this service).

As for the Ufer itself, the current plan was to embed a larger than normal line (4/0) in ~80’ of wall. Adding to this, the wall is relatively tall (15’), so a side question is: Is it okay/a good idea to loop or branch the 4/0 to cover more surface area? Yes, it will be tied to the rebar (5/8") everywhere, but “probably” the copper is going to have a better chance of spreading a large discharge without damaging the concrete if it has more surface area to use, correct?

Does any of this sound like a good idea?

Thanks.
 

tom baker

First Chief Moderator & NEC Expert
Staff member
Location
Bremerton, Washington
Occupation
Master Electrician
Your user profile suggest you are a DIYer and we are unable to assist per forum rules. There are a number of companies that specialize in lightning protection that can assist.
 
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