Blitzschutzleiter / Lightning Conductor

Me again!

Do I really need a lightning conductor on a normal house?
Or is it just the usual paranoia going around, everybody watches a documentary on tv and suddenly everyone needs a lightning conductor.

I have never seen a conductor on a normal house, on a large building/church of course, but not on a 3 bedroom semi. But a friend says he has one on his house. We then looked at the houses nearby and decided that none of them had one.

Is it overkill, or is it just that we live in a very dangerous area?

Neil

Our neighbour's house was damaged by a lightening strike a couple of years ago. They live in a Fertighaus (pre-fab) and the force of the electricity caused the Rigips boards to come off the walls in the cellar, and the wiring burnt through and smouldered. They had to carry the cost for all the repairs, which took several weeks, themselves because they weren't insured.

As this wasn't a direct hit - the lightening actually struck the garden pump miles away at the bottom of the garden, and travelled through the connection into the cellar, a conductor would have been no use. They are also now insured for "Überspannung" (check your policy, not everyone is), and not for only a direct hit.

By the way, we have had three direct hits immediately around us during the past four years. I'm beginning to wonder if there is something in the ground around here ...

Buy one if when you hear the phrase 'Your chances of ... are about as high as getting struck by lightening', you think, 'Gee, that is pretty bad, isn't it.'

You know what these Germans are like. They see a reportage on Stern TV and the next day everyone is buying lightening rods (or not buying potatoes becasue they give you cancer, or banning cars because of the feinstaub that somehow hasn't killed them yet).

Unfortunately lightning is not predictable and the old adage that “lightning never strikes twice in the same place" is akin to saying a lead brick won’t sink if thrown into a lake.

Tall buildings, towers etc. are struck repeatedly by lightning. Lightning is indiscriminate and will seek whatever path offers the least resistance. So if your house is taller than those around you there is a greater chance that lightning may find your chimney stack offers the least resistance.

The lightning conductor is not an ‘attractor’ as some may think, just because your neighbour has one... he'll be hit and you won't is a false sense of security; however, it does give the current the easiest path to earth, avoiding the transfer of current through less conductive building materials and the consequent structural damage that this can cause.

The answer to not having your property damaged by a direct strike is to not be in the path lightning has chosen. And remember, as already said, the conductor is only any good for direct strikes.

Our house got hit by lightning twice within two weeks. The house next door has a lightning conductor, but one part of the lightning set the gable part of the roof on fire. We also had serious flood damage a month later. We're lucky aren't we!

A lightning protection system is apparently very expensive and way beyond our budget. I spoke to a profi about this and he suggests that lightning conductors only reduce damage. I stopped any more research afterwards, so any further opinions would be interesting. Some of our damage came through the telephone lines. One hit destroyed the telephone distribution box on the street outside.

Protection system

I havent read the above article, but I will later..

From what I understand, the "Lightning protection" is simply designed to bring the whole building the same electrical potential, ie, If your TV antenna, chimney etc are not earth bonded, then you are more likely to to get a lightning strike that if you do have the protection.

If you do get hit, these protection rigs are pretty useless.

A 16mm² earthing cable explodes as it takes a direct hit..

so, if your neighbour has it, and you dont, your house has a higher electrical potential and you house will"attract" the energy...

Morall of the story... "Keep up with the Jones"

:$

G

Most newer policies have this cover, however, until about five or ten years ago it wasn't so common, so if you have an older policy it's certainly worth checking.

Überspannung is much more common than a direct lightning strike and can occur when the lightening strikes 200m and more away from the house.

Lightning conductors, properly installed, do provide some protection, however, decent protection systems are expensive, as a rule a single mast is not enough, you really need a sort of net with multiple masts and substantial earth routes. Much more important, if not properly maintained, they can become more dangerous than no lightning conductor as high impedance connections where connections loosen and rust provide a high temperature source which can start a fire. Regular maintenance is not cheap!

As a process control engineer I have been involved in lightning protection of control rooms on many occasions. What I have learnt there leads me to the conclusion that domestically it's not worth the trouble - just make sure you're properly insured!

Thanks everyone. Don't think we will be getting one, not least as we dont have too much spare cash floating around.