kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
My question is what do you bond a very thin piece of metal with that can take thousands of amps without destruction of the bonding point?
If lightning strikes the far corner of roof from where the bond is made you will also have potentially hundreds of pieces for current to travel through to get to the grounding conductor, each with poor electrical joints between them.
There will likely be burn marks at every joint, that is if you are lucky enough there was no fire afterwards and everything is still intact.
Metal roofs are not really that new - just a newer concept on dwellings. They have been around on farm buildings for years and have no more or less lightning incidents than asphalt or wood shingles AFAIK. I have seen more houses on farms with severe lightning damage than I have seen outbuildings over the past 20 years or so.
I do see other lightning damage on farms away from the house - there is just typically more in the house subject to damage. I remember a few years back lightning struck a customer side distribution pole on a farm. There was buldings with metal roofs around, some taller than the pole, yet the pole was obviously the direct hit as it was split pretty good.
There was damage of a few items here and there of electrical items in some nearby buildings. The house was one of the farther away structures yet had the most items effected. Somewhere it crossed to the telephone lines and about every phone and phone jack needed replaced. The phone companies surge protector on outside of house had cover completely blown off of it.
If lightning strikes the far corner of roof from where the bond is made you will also have potentially hundreds of pieces for current to travel through to get to the grounding conductor, each with poor electrical joints between them.
There will likely be burn marks at every joint, that is if you are lucky enough there was no fire afterwards and everything is still intact.
Metal roofs are not really that new - just a newer concept on dwellings. They have been around on farm buildings for years and have no more or less lightning incidents than asphalt or wood shingles AFAIK. I have seen more houses on farms with severe lightning damage than I have seen outbuildings over the past 20 years or so.
I do see other lightning damage on farms away from the house - there is just typically more in the house subject to damage. I remember a few years back lightning struck a customer side distribution pole on a farm. There was buldings with metal roofs around, some taller than the pole, yet the pole was obviously the direct hit as it was split pretty good.
There was damage of a few items here and there of electrical items in some nearby buildings. The house was one of the farther away structures yet had the most items effected. Somewhere it crossed to the telephone lines and about every phone and phone jack needed replaced. The phone companies surge protector on outside of house had cover completely blown off of it.
