Generally speaking, water leakage in the color steel roof of steel structure building is mainly caused by self-tapping screws, color steel lap joints, roof tiles, blind rivets, deformation of the color steel plate caused by people on the roof, and rainproof glue falling on decoration parts such as lighting windows. The corresponding leakage points can be divided into the following points:
1.Water leakage at roof screws and fasteners
This phenomenon mainly occurs in double-layer color steel plate and single-layer color steel roof. During the construction process, the self-tapping screw is too heavy or too light, the self-tapping screw is deflected or skewed, and etc., which may cause the self-tapping screw rubber gasket to deform, fall, or form a concave surface, and resulting in dripping and leakage of the roof. After accumulation of thermal insulation cotton to constitute more leaks. In addition, the misalignment of the self-tapping screw will miss the purlin under the color steel plate and directly forming a hole is also one of the important reasons for water leakage. This kind of water leakage may not be significant in the roof structure of single-layer color steel plate without thermal insulation system, which mainly because the rainwater flows directly after leaking through the part where the steel plate and the purlin joint.
2.Water leakage at the overlap of color steel plates
The water leakage at horizontal lap joints and vertical lap joints, and the color steel plate lap joints. If the color steel plate tile wave is too low or the rainwater volume is too large, it will simply form a large area of water leakage, and it is difficult to find water leakage points. It is not easy to repair, and this situation is more common in curved roofs. The main reason is that the overlap between the two boards is not tight, and the self-tapping screws are not full to form an open space.
3.Water leakage at the roof tiles
In the construction of light steel structure roofs, water leakage caused by roof ridge tiles is also a common phenomenon. In the rainy season, especially when the amount of rain is large, the splash of rainwater passes through the gap between the two color steel plates under the ridge tile, and forming a large area of leakage.
1.Re-waterproof the entire roof
This plan can make the color steel plate roof form a waterproof layer. And the self-adhesive coils will be recommended to use. Self-adhesive coil is a kind of waterproof and sealing material that can bond with the base surface. It is divided into two types: self-adhesive with tire and self-adhesive without tire. The self-adhesive with tire is composed of the upper and lower self-adhesive glue and the middle sandwiched tire base. The upper covering surface is a vinyl film, and the lower covering surface is a peelable silicone oil film. Tireless self-adhesive is composed of self-adhesive glue, upper vinyl film and lower silicone oil film. This coil has self-healing properties, that is, when the coil encounters punctures or embedding of hard objects, it will actively integrate with these objects and still maintain a good waterproof function. And the upper skin is made of pure metal aluminum foil, which has the effect of heat resistance and heat insulation. The temperature of the color steel tile can drop by 5-10 degrees in summer.
2.Waterproof the roof screws and fasteners, color steel plate lap joints and roof ridge tiles
The construction process is: finishing the bottom layer → painting the bottom layer to treat the waterproof materials → construction of the additional reinforcement layer → painting the waterproof coating.
The above two plans can effectively control the leakage of the color steel roof. The specific selection can be judged according to the construction area and other factors.