Lightning protection and NFPA 780


Old 01-11-20, 09:35 AM
Thread Starter
Join Date: Oct 2005
Location: USA
Posts: 1,693
Received 47 Votes on 46 Posts
Lightning protection and NFPA 780

I am designing a lightning protection system for my new boathouse. it sits over salt water, around 5 feet water depth. NFPA 780:2008 doesn't really cover over water structures well. Although it does consider watercraft themselves.
My structure will be alongside a seawall, with clay under turf. I'm going to suspect that I don't need to drive ground rods underwater, but that a short horiz run of grounding conductor can cross the seawall to find non-submerged dirt. Note that I already need a #6 running from a subpanel in the boathouse to one or more ground rods.
Also, any comment on the idea of submerged copper sheathing around wood piles? The structure will have a dozen 10" dia piles driven in the canal.
There is a high chance of lightning strikes in this area; my friend's sailboat was hit directly last summer, one canal over. It devastated his shore power system, aboard and ashore.
Old 01-11-20, 01:53 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 60,786
Received 1,324 Votes on 1,224 Posts
Is your boathouse high over current terrain ?
A boathouse is not a typical building associated with lightning strikes.
A sailboat with a tall mast would be.

Is this a saltwater area ?
The salt will kill most anything in the ground near it.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: