Among the owners of private houses and cottages, and sometimes even among professional builders there is an opinion that houses with a metal roof do not need lightning protection. This is a very large and dangerous misconception.
Lightning protection of a metal roof is necessary, both external and internal.
Why do houses with a metal roof need it?
The roof is made of metal rolling, clean steel, but in most cases it is installed on a wooden crate and a black wooden roof (in the case of a metal tile).
When lightning enters, the metal roof heats up to a temperature, much larger than the burning temperature of the wood. There is a fire, which is local.
Why is internal lightning protection of a metal roof needed?
It is needed:
to reduce the effects of electric discharge and electromagnetic radiation indoors during a thunderstorm, if lightning strokes into the roof;
to reduce the risk of sparks;
to ensure a stable voltage in electric networks;
To ensure the normal operation of household electrical appliances.
How to establish internal lightning protection in a wooden house?
For a metal roof, it is installed directly under the roof. Its task is to ensure the transfer of excess electricity deep into the ground through a complex of thunderbones or a special device.
It is quite difficult to establish internal lightning protection of a metal roof, certain skills and knowledge are required. Given the importance of this device, it is necessary to invite a specialist.
There are craftsmen, at their own peril and risk, exposing the metal rods and connecting them with grounding in the yard. If you decide on an independent installation, you must have:
metal reinforced bar with a thickness of at least 0, 7 cm;
an introductory-distribution shield with thunderclines (resistors);
metal tank for instillation underground as deep as possible;
welding machine;
Clamps and brackets.
The cost of the work of an invited specialist for installing an introductory-distribution shield with thunderstorms and eyeliner to ground and lightning receiver costs an average of one and a half thousand, depending on the region, the area of the house, the area of the metal roof, its nature (flat or sloping) and the quantity) and the amount floors in the house. In general, this is not such a large amount to save on their own safety, the safety of the house and the safety of property.