1. Water leakage at roof screws and fastenershenomenon mainly occurs in the double-layer color steel plate and single-layer color steel plate roof. In the construction process, the tapping force is too heavy, too light, self screw deviation, skew, etc., which may make the self tapping rubber gasket deformation, fall off or form a concave surface, causing the roof drip water leakage, and accumulating through the insulation cotton, the accumulation makes a lot, forming multi-point water leakage. In addition, the position of the self tapping wire is not right, missing the purlin under the color steel plate and directly forming holes is also one of the important reasons for water leakage. This kind of leakage phenomenon may not be obvious in the roof structure of single-layer color steel plate without thermal insulation system, mainly because the rain water directly disperses through the contact part of steel plate and purlin, and does not necessarily drop rapidly.
2. Leakage at the lap joint of color steel plate
If the tile wave of the color steel plate is too low or the rainfall is too large, it is easy to form a large area of water leakage, and it is not easy to find the leakage point. Once it is formed, it is not easy to repair, this situation is more common in the arc roof. The main reason is that the overlap between the two plates is not tight, the self tapping wire is not full, forming a gap and so on.
3. Roof tile leaking
In the construction of light steel structure roof, water leakage caused by roof ridge tile is also a common phenomenon. In the rainy season, especially when the amount of rain is large, the rain splashes through the gap between the two color steel plates at the lower part of the ridge tile, forming a large area of leakage.