lightning rods

[grsthegreat]

Ground rods and lightning protection are two very different things.

 

[yanmars]

I should have given more info. The building is frame, no electricity yet but coming. Attached lean to is a metal roof, main roof is asphalt and siding is vinyl. I have copper ridge cap I wish to add. Just wondered how much concern with that. Hope it gets hot enough also to burn the feet of buzzards so they quit landing up there.

 

[PILOON]

We were once visiting friends that had a ceiling lamp hanging.
During an electric storm we all observed a bright streak of lightning flash its way down that ceiling fixture followed by the room going dark.
Scary!

 

[grsthegreat]

i know for things like cell towers, where they drive in a crazy number of ground rods for protection, most houses only use 2. i dont hear of many issues with lightning strikes hurting things. i have had a few generator repairs from lightning strikes, but very few considering the number of lightning storms we have here.

im thinking that modern houses have a much better grounding systems then those of the past where lightning rods were required.

 

[Rustyiron]

They are a real "thing". Mostly on commercial buildings now from what I've been told. This guy was in the mid Atlantic area and showed me pictures of inside the cast iron framework of the Capitol dome. They were doing service work on the lightning protection system.

 

[grsthegreat]

i did see one house up here years ago where the homeowner installed his own lightning rod system. he connected all the rods with a 2/0 bare copper wire. then he drilled every truss on the house at peak and ran the 2/0 thru the hole.... between rods.

the electrical and framing inspectors failed him. told him in a lightning strike the bare copper could heat up and burn the house down. PLUS...he was never allowed to drill a truss...i was working for another contractor at the time on an independent generator install, so never did find out what the final outcome was.

 

[BravoXray]

Probably 30 years or so back, I was in bed watching satellite TV (old school 10 foot dish with receiver and positioner) when a storm rolled in with lots of lightning. All of a sudden, the window facing the dish, just 20' from the house, lit up with a tremendous crash. TV went out and I soon smelled smoke. Yikes! Got up, turned on the overhead light, it on a separate circuit from the wall outlets, and saw smoke coming from the Sat receiver. I pulled it out and there was no fire, but I disconnected it and the positioner from the dish cables. Got dressed, went out in the rain to make sure the house wasn't on fire, it wasn't, so I went back in and eventually went back to bed.
Next day I looked the dish and LNB over and found the coax was blown apart in a couple of places, but no other damage. LNB was DOA though when I got a new receiver. Fortunately, insurance paid for everything.
Another time, about 15 years ago, lightning hit the utility pole by the road and took out the transformer, a couple insulators, a TV, microwave and some light bulbs. In my bedroom, it blew apart the molded plug on the night stand light and scorched the outlet. It also blew the bark off a strip 6 inches wide and 20 feet high on a large poplar tree near the pole. A root near the buried electrical service also burned a hole in the cable's insulation, and two years later, almost to the day, the corroded cable gave out and power to the house went out. The utility company ran a temporary line and later dug up the cable and found the bad area.

Still, there's nothing like a good storm with lots of lightning.

 

[tomplum]

here's a trick i learned the hard way. if you are having trouble pounding the rods into the ground, run a little water down the rod, just spill a little on the rod and it becomes much easier to drive.

Works. Though with one I had a bugger of a time. Made a water drill out of a piece of metal conduit which got the job done.

 

[MHarryE]

My dad and uncle built their barn in 1946, ran a heavy copper cable from the roof (bolted to one galvanized steel panel) to a long copper ground rod. Barn has been struck several times as witnessed by burned grass around the ground rod (and we were milking one time when it was hit - loud, socking experience). My place now has 4 large pole buildings with no provision for grounding roof. Is the difference painted panels not conducting between each other?

 

[CoyPatton]

i know for things like cell towers, where they drive in a crazy number of ground rods for protection, most houses only use 2. i dont hear of many issues with lightning strikes hurting things. i have had a few generator repairs from lightning strikes, but very few considering the number of lightning storms we have here.

im thinking that modern houses have a much better grounding systems then those of the past where lightning rods were required.

Since many homes build in the early 60’s and before basically had little to grounding system. Throughout the home, they are much better grounded today than in the past. I have been in homes that had no grounding system at all, others that had small gauge (18 ga at best) in the kitchen and bathrooms attached to the rear of the box. These were 2 prong 2 wire systems. So yes much better grounding in modern homes/buildings.
Now do you wish to consider grounding rods?
Many of those homes did not have ‘ground rods’ installed. Again often small gauge ground wire used for the panel in general, and this was often clamped to water lines potentially electrically charging the water fixtures in the home. Yes modern homes/buildings have much better grounding than homes from the early days of installed electricity in homes.
Praise GOD for these blessings!