What Are The Causes Of Water Leakage in Metal Roof Plate System

1. Hidden water leakage caused by material characteristics:
(1) The roof metal plate itself has large thermal conductivity. When the external temperature changes greatly, the roof is also very sensitive to the ambient temperature because of the large change in the ambient temperature difference. The displacement is large, the metal material has many thermal expansion and cold contraction, so that the elasticity and cohesion of the sealant becomes smaller, and the effect is soon lost. Therefore, water leakage is very likely to occur in the metal plate interface position.
(2) In the steel structure system, because the structure itself is prone to elastic deformation under the action of external forces such as temperature change, wind load and snow load, the roof metal plate will be displaced at the connection site, causing potential water leakage.
(3) Special parts, due to the use of different materials for connection, such as parapet and steel plate made of gutter, roof lighting strip and other parts of the connection, due to the force change is not synchronized, there is a potential water leakage.
(4) The main reasons for the deformation of color steel tile roof: first: the roof span is large, the middle water for a long time, the middle gravity increases. For cotton roofs, mineral wool absorbs water. On rainy days, the roof leaks all the rainwater will gather in the mineral wool, the weight will increase.
(5) wind, rain and other external forces make the color steel tile roof long-term vibration, resulting in nail holes, iron joints long-term wear, rain rust. Then wear and rust, worse and worse, leading to water leakage.
2. Hidden water leakage caused by roof design or plate shape defects:
(1) In the fierce market competition, the construction side blindly reduces the cost in order to undertake the task. In order to save raw materials, the slope of the house is reduced in the structural design, some of which are even lower than 1/20, which is easy to cause water and water leakage.
(2) The roof structure system is unreasonable, the roof panel will crack under the repeated action of thermal expansion and cold contraction, which will inevitably cause roof water leakage and cannot be completely solved.
(3) Due to the cost factor, at present, the profiles used in light steel houses are mostly plate types with wave height (large effective area) and small lap width. When the house is flooded, it is easy to overflow.
(4) The structural design does not fully consider the regional characteristics, resulting in waterproof defects: At present, in the design of light steel structure, no different waterproof measures are taken for regional climate differences. For example, the waterproof measures in the environment of Meiyu in the south, monsoon typhoon in the coastal area and the waterproof measures when the snow melt in the northeast have structural characteristics. We should choose the waterproof material suitable for this region.
(5) High, low span roof, wall foot of the flushing part, the corner with cement wipe, sealant or waterproof coating waterproof protection. Cracks occur when cement and metal do not bond. The elongation of smaller paints or sealants can also lead to larger cracks and leaks.
3. Waterproof defects caused by construction factors:
(1) aluminum magnesium manganese metal roof plate in the process of production and transportation inadvertently deformation.
(2) In the construction process, the pressure of body weight causes the gap between the metal plates to widen and deform.
(3) The self-tapping screw damaged the rubber pad during construction, and soon lost its waterproof function, causing water leakage.
(4) return water phenomenon is a unique phenomenon of color steel roofing, the formation of the necessary conditions are: return water inside and outside ventilation. First: in rainy days, there is a pressure difference between indoor and outdoor, and the indoor pressure is low. Second: the outdoor strong wind in the ventilation area to form a duct, the wind will force the rain back into. The main reason is improper treatment of construction joints.
According to the above situation, horizontal lap joint, vertical lap joint, fan outlet, roof protruding pipe, air conditioning pipe, light plate around, ridge, gutter, metal plate and parapet joint flash point, screw fasteners and other metal roof waterproof weak link.