The lightning protection belt and its connecting line pass through a settlement ditch (settlement ditch: a long multi-storey building, which often divides the building into several sections horizontally, leaving a gap between sections to prevent inconsistent settlement of each section. When causing damage to the building), a spanning cable with an expansion and contraction margin of 10-20cm or more should be provided.

For flat-topped houses with parapet walls, when the width is less than 24m, only need to lay lightning protection belts along the upper part of the parapet; When the distance is not more than 20m, only install lightning protection strips on the eaves; when the width is more than 20m, it is necessary to install exposed connecting strips on the roof, and the distance between the connecting strips is not more than 20m.

When the slope of the tile-roofed house is 27°-35° and the length does not exceed 75m, only the lightning protection belt is laid along the roof ridge. For houses with four slope roofs, lightning protection belts should be installed on each slope ridge. In order to protect the corners of the eaves, short lightning rods should be installed on the corners or the down conductor of the lightning protection belt should be wound from the corners of the eaves. If the height of the eaves is greater than 12m and the length is greater than 75m, lightning protection belts shall be laid on the roof ridge and eaves.

When the roof area is very large, a metal grid, that is, a lightning protection net, should be laid. Lightning protection nets are divided into clear nets and dark nets. The denser the grid, the better the reliability. The density of the grid depends on the importance of the building. Important buildings use dense grids of 5×5m, and general buildings use 20×20m. The grid is fine.

On non-concrete structures, exposed lightning protection nets can be used. The method is to first install the main net of lightning protection belt on the protruding edge part of the roof ridge, eaves, etc., and then add an auxiliary net on the main net. The size of the lightning protection grid shall be in accordance with the above requirements. When using lightning protection belts and lightning protection nets, the chimneys, concrete parapets, exhaust buildings, skylights and architectural decorations on the roof that protrude from the upper part of the roof and other protruding parts should be protected by short lightning rods or lightning protection belts. Or conceal a protective line and connect it to the nearest lightning protection belt or lightning protection net.