Lightning rods & metal roofs

Related to previous query: We are installing a new Englert Metals galvalume with Kynar 500 metal roof on our house on the Chesapeake Bay. I read somewhere that we should not use a lightning rod because it can damage the chemistry of this material and cause damage to the paint bond. Is this true? If not, what kind of lightning rod system should we use? The house is an updated farm house originally built in 1880, with additions. I am unaware of any other "grounding" of the house or roof, other than the old lightning rod that our roof installer suggested we remove and replace. Our installer suggested using a new lightning rod that gets installed by inserting it up thru the roof from the attic. Any suggestions?

While dissimilar metals will have some galvanic interaction, there are grounding systems that are designed to work with galvanized steel.

Give your location, did they run aluminum or galvanized steel in this case?

Thanks. My location is in Kilmarnock VA and our house is right on a point of land on brackish water that feeds directly to the Chesapeake, which is visible from our house. We are in an area with strong storms, high winds, and presumably significant lightning exposure -- a neighbor not too far from us relates how their 35 ft sailboat got destroyed by lightning a few years ago.

If you are asking about the new roofing material, Englert Metals galvalume is produced in the factory by "coating steel with a special Aluminum-Zinc alloy that provides more than twice the corrosion resistance of galvanized steel by delivering the optimum combination of the features of aluminum and zinc." (from Englert's website)

I was asking about the roof being based on a steel panel or aluminum

In that proximity to salt water, the roof really should have been formed with the base material being aluminum in this case.

I may not pose you any problems in this case and there are lightning grounding systems that are designed to work with steel that will work just fine.