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TOPIC: Hurricane Concerns

Metal roofs and LIGHTNING

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My wife wants a metal roof. We live in the Tampa area which I believe is the ligtning capital of the United States. My concern is that we have been hit by lightning which has knocked out our phone at least 3 times. Thank goodness for lightning rods. How will a metal roof handle such severe lightning????? Lance
Lance Ott

4/10/2005
Very common question. Metal roofing actually acts as a shock absorber if hit by lightening in that it is able to disperse the charge quickly over a larger area. I personally have witnessed a strike on a metal roof from 100 feet away and watched the energy discharge in a blanket across the roof and back into the rain with no damage.
Allan Reid
Dura-Loc Roofing Systems, Inc.

4/11/2005
Metal roofs must be well grounded to afford protection else they will provide a superior conductive path for the energy to enter and damage the structure's electrical and structural (rebar) systems. There is frequent evidence here in Florida where curbs have been damaged, large chunks of concrete curb blown for several yards, due to expansion from the nearly instantaneous heating when ground strikes are conducted through the curb's rebar. A direct hit on a concrete block structure can result in the block wall being similarly damaged. What studies have been conducted to support recommendations for the proper grounding and electrical bonding of metal roofs?
Guest User

7/6/2005
This almost sounds like a sales pitch for a lightning arrester system. When lightning strikes it is typically during a rin storm and it will tend to boil the moisture in the substrate that it strikes which causes the damage. Fact is that metal roofs do not hold any moisture and actually dissipate the electrical charge and unlike other products, so you will have significantly less damage with a metal roof. As to tests, we let mother nature do that and I for one have witnessed lightning strikes on metal roofs and they truly dissipate the charge with no damage.
Allan Reid
Dura-Loc Roofing Systems, Inc.

7/7/2005
If the house site had numerous trees previously struck and the house is now the tallest structure, therefore a lighting rod system would be installed if a non-metal roof were used, should a lighting rod system also be installed if a metal roof is used or is it unnecessary?
Guest User

12/30/2007
It would be fine to install it.
Todd Miller
Isaiah Industries, Inc.

12/30/2007