How do these homes respond to lightning?

TF;

that is a great question and one that is occasionally asked............

Steel built homes are less likely to be damaged by lightning strikes because they have superior grounding characteristics.  In fact, a steel frame building provides better protection from lightning than any other type of construction material.  This is because the steel frame provides a path to the ground, thus reducing the likelihood of secondary fire, or even personal injury.

as a side note:
A shorted romex wire in steel framing is also not likeley to  cause an electrical fire as it would immediately pop the circuit breaker,
where as a shorted wire in a wood frame assembly could continue to arc until the wood catches fire
 

TFreidman,

Lightning proof is a good description.  As is the case with any metal structure such as a car, or plane, the metal sip is your safest place to be in a lightning storm.  You are safe in you car not because as is commonly believed you have rubber tires, but because you are surrounded be metal.    A lightning rod is not there to attract lightning but to make a way for the structure to release the build up of ions that naturally accrue. Ion build up is what attracts lightning.  Also as is the case with an airplane or I have even seen demonstrations with a suit of armor, lightening will go around the outside circumference of any metal structure and dissipate into the ground. If properly grounded you have a greater chance of no damage what so ever in a steel sip structure than you do with any other type of construction, should a lightning strike ever happen.

CKavala   nice video, is there anyway isolate and download the video, I think it shows in a few minutes a wealth of info.

I would add that the only way lightning would hop off of a metal structure (stud or SIPs skin) and go through air, wood, or flesh instead would be if the metal were not grounded, and the other material provided the necessary path to ground.  So if there is a break between two metal members and you happen to be spanning that break (touching both at once), the current will flow through you.  A piece of wood could also provide the bridge, likely leading to a fire.

However, none of this makes metal any worse than wood construction, and in fact whatever breaks there are in a metal structre between the metal members and ground are likely small enough gaps that the path of least resistance will be the air between the members.  If you really care, make sure that metal fasteners connect the entire metal frame into a singly connected structure all the way to ground.  You can even add a grounding lug at the bottom to ensure a good connection.  Of course, by doing that you will also be creating what's called a "Faraday cage", which will pretty effectively block radio signals (including your cell phone).  Unless you are paranoid that the high voltage power lines and cell towers are giving you cancer, or that the CIA is reading your brain waves with spy satellites, you probably would rather be able to get a cell signal in your house.  So don't try too hard to ground the metal skin.   Studs are not spaced closely enough to create a faraday cage; you need a solid skin or fine metal mesh to create a Faraday cage, and it has to have a good ground connection.  Anything less will attenuate but not completely block radio signals.

When the meter can and breaker panel are attached to the steel building it is automatically grounded with the electrical system

looks like a northern home?