This question is from new user Dfitzen and spouse.  When should lightning rods
be used?  They live in the  country near Chelsea, and it hits all around them,
the well, and their neighbors lost a barn.  ANother one lost a well, it burned
their well up.  Some trees have been hit.  And of course their son was in the
shower and he got hit, and then it went down to the neighbor's house and took
concrete off the porch.  It knocked out the telephone in the house, and the
retaining wall.  They were lucky and have not been hit yet, it was in the yard
someplace but did not hit the house.  Any information would be helpful.

12 responses total.

The fact that you get no reduction on your homeowner's insurance for having
lightning protection should tell you something. From the insurance industry's
viewpoint, lightning rods on dwellings are not worth it. 

I've seen the result of lightning strikes on trees, but I've never experineced
a strike close enough to observe effects (other than light and noise), nor
has any house I have lived in been struck or even anything damaged by
lightning. The only person I know that was hit by lightning was climbing in
a cave, and got knocked off his perch. 

I have been on top of a mountain when a storm came over in August, and my
hair stood on end and buzzed (probably would have looked very weird if it
had been night - the only time I would ever have a halo), but there was
no strike. 

The most serious instances of damage from lightning that I know of is to
sailboats without grounding of the mast to the keel. Lightning will blow
a hole through the bottom of the boat and sink it, if there is not a
grounding strap to conduct it outside or through the hull safely.

I don't doubt the instances of which you speak, but from what I know the
best personal protection is to stay away from conductors (antennas, water
pipes, electric circuits, etc) in houses during lightning storms, and the
best equipment protection is normal electrical grounding practices. 

Hmmm.  Buildings out in the countryside have traditionally been well-
equipped with lightning rods.  No neighbors to notice a fire or help
put it out, fire department's a long ways away, and the phone you need
to call 'em may have been knocked out by the storm, too.  My bet would
be that those old-time farmers were right to put up lightning rods. 

The best person to ask would probably be the local fire chief or an
agent experienced in rural property insurance.  But being insured is
usually a poor second to not suffering a fire. 

Adding a lightning rod couldn't hurt, though.

Unless they didn't maintain it, and after a few years the ground connection
was lost somehow.  

I had read some time ago that the prevalence of lightning rods in the past
on barns and buildings was primarily due to some very aggressive sales people
for lightning rod manufacturers. It is easy to scare people about this and
sell them something that actually doesn't do much good at all. But,
if anyone can come up with actuarial statistics to show a connection between
lightning rods and a lower incidence of lightning damage, I'd be glad to
see it. Consider, though, that no lightning rods are installed as a matter
of course is all the new development that is occurring.

You won't win anything by portraying mass developers as people who would
spend money to add a feature that is not on most people's checklist, Rane.
;)

I just can`t imagine getting struck by lightning in the shower!  Would it
matter if it had plastic plumbing?   Would it matter if you had a metal drain
or not?  Or visa versa?  On another note, what about cordless phones?  Is
there any danger there, besides the unit?  It's common knowledge that the
tallest structure will get hit or "grab lightning".  If your house is next
to a tree bigger than your house (2x) (black walnut tree), does the house need
protection?  SIDEBAR. -- You could use a lightning rod to generate electricity
from the wind passing the sharp point of it.  It actually "bleeds" off a
charge that you could store in a battery.  If the lightning rod is hit by
lightning although, it wouldn't be good.  Someone recently watched a PBS
special on lightning (deigert) and said that underground cables are as prone
to be hit than overhead cables.  Where is the rational for this.  He doesn`t
remember.   Message thought up by Jim Deigert and typed by D.D.

Stay out of the shower in thunderstorms! Water makes a fine path for
a stroke to follow, regardless of the pipe material. A metal pipe might
actually help direct the stroke to ground so you are friend a little less.

There would be no hazard from cordless phones. 

The ground is not a particularly good conductor. The lightning stroke is
between charge differences between the cloud and the ground, but the
charge is disseminated throughout the ground above the water table. Thus
the stroke behaves in the ground somewhat like it does in the air - following
the most conductive paths. Underground cables above the water table are
much better conductors than the ground, so will attract the discharge,
especially if their insulation can be pierced by the discharge.

Generally the higher tree will attract the stroke better than the adjacent
house, but not necessarily. It also depends upon the ability of the structure
to either bleed off the local charge difference in corona discharges or
create the leader by that same corona discharge. Buildings have wiring
in them which is much better at creating high local fields than are the
less conductive and pointy trees. 

My 8 year old daughter saw ball lightning outside our front window not
too long ago.  Our neighbors tell us that our house took an indirect hit
about 3' from the foundation (No damage) before I moved there.  A neighbor
lost a *huge* American Elm a few summers ago from a strike. (The siding
on their house was plastered by wood debris.)  I've heard plenty of stories
of families huddled in the middle of a living room while lightning dances
around the outlets and in the kitchen.  Houses seem to survive lightning
pretty well.  The house we are currently in is in a 1950's suburb in Ann
Arbor.  The house I'm building is in a very high and exposed area in Dexter
township.  None of the neighbors have lightning rods and nor will I.  I
have also read some pretty interesting studies on lightning protection
that indicate to me that the lightning rods you do see are totally
inadequate.  The have far too few points on them and require a far better
ground.  (10" wide Cu strip with only gentle bends and all joins bolted
together.  This would then have to be attached to a significant ground
system consisting of several ground rods driven into the ground.)

thank you we have printed your reply we will read  thank you 

They showed us where the lightning hit, even though they are surrounded by
trees.  Jim thinks there may be underground water that the lightning strike
followed.  Dorothy printed out the whole item (on some rather strange paper
- it comes three sheets together and makes its own light copies) and they will
read it at their leisure.

I've often wondered how effective those lightning rods on barns are.  As Klaus
has pointed out, you would need a pretty big conductor to effectively ground
the rod.  It does seem to me that the best sources of information would be the
insurance companies.

See #1.

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