Lightning Strike Maryland

Denise and Mark Moynahan
Backbone Mountain, Maryland
Lightning Strikes Dome (1991)

(June 2008 update – make that 3 lightning strikes)

Denise and Mark build a 46′ dome mid-profile dome about 200′ away from the top of Backbone Mountain, the highest point in Maryland.

Mark is an engineer, inventor, and imaginative owner builder.

They have an open dome framework and a second floor deck hung from the outer dome struts along with a view cupola.

Now, a 3,360′ high mountain top may seem like a foothill in other parts of the country. But the views from the 2nd floor deck and cupola are mighty breath taking.

So, back to the story of the lightning strike. It occurred during construction. The dome shell was up, the exterior was finished and the interior was being insulated. Mark and his helper were up on top of the dome completing a project. With this view you can see across the valley for 40+ miles. They saw a storm approaching and decided to take a coffee break and see if the storm would pass by.

Mark, the creative inventor, had installed a lightning protection system on the top of this cupola. There was a lightning rod at the top center and 5 copper wires leading down to 5 ground rods. They had connected all of the major metal dome components to these 5 grounding wires.


As they were sitting in the dome watching the storm go by, there was a lightning flash and there was no pause to the loud “crack” after the flash. They looked up to the cupola and could tell from the “air” around the cupola that it had been a direct hit. They waited for the storm to get far enough away and then went out on top of the dome cupola. They figured the lightning strike had vaporized over ¼” of the lightning rod! After checking the other parts of the system, they saw no other damage – and began to ponder what would have happened without the lightning protection system!

June 2008 update :

Mark has informed us that there have been 3 lightning strikes over the life of the dome. All of them have been dissipated through the lightning protection system he had installed. There has been no damage to his dome home. We can start a new adage : People who live in dome homes on mountain tops should always install lightning protection.