Most of the squatter's shelter are made of zinc, why is it safer than a shelter made of wood? Good question.
1. Wood is termite's food except teak wood.
2. Zinc forms what scientist call a "Faraday's Cage" whereby the charges are resided to the surface the zinc shelter & leaving the occupant inside safe in case of a lightning strikes.
3. A test shown that when the voltage is increased to a certain limit, wood actually got struck & blown to smithereens.
An important device in applied electromagnetic study and research and the applied science of the same field is the Faraday cage. The Faraday cage is a device that cancels out all electrostatic fields within the space that it encloses. Typically it is a metallic enclosure or cage that eliminates all electric fields of static nature by rearranging the charges within itself to such an extent such that there is no electric field. This is an intrinsic property of conductors and has been used ever since it was first discovered in the early 19th century. (Plucked from: www.faraday-cage.com)
However, zinc is a good conductor of heat & vibrations making inside an oven during the day & a tin can of noise.