这种现象主要发生在双层 彩钢板和单层彩钢板屋面。施工过程中，自攻力过大过轻，自攻螺钉偏斜等，可能导致自攻胶垫变形、脱落或形成凹面，造成屋面滴水渗漏，并通过保温棉积聚，积聚越来越多，形成多点漏水。另外，自攻丝位置不对， 彩钢板下檩条漏掉直接形成孔洞，也是漏水的重要原因之一。这种漏水现象在没有保温系统的单层彩钢板屋面结构中可能不明显，主要原因是雨水渗漏后通过钢板与檩条的接触部分直接分散，不一定滴水迅速。
The slope of color steel sheet roof is generally small, often below 6%. This kind of structure is common in the areas with more rain in central and southern China, with large area of water leakage, light window and roof ridge joint. It is necessary to
understand and analyze the structure, leakage point and cause of color steel sheet roof when it is used to treat the leakage water.
Generally speaking, the water leakage of color steel plate roof is mainly caused by self tapping screw, color steel plate lapping, ridge tile, pop rivets, color steel plate deformation caused by people on the roof and rain proof glue falling off of lighting windows and other decorative parts. The corresponding leakage points can be divided into the following points:
1. Water leakage at roof screws and fasteners
This phenomenon mainly occurs in the double-layer color steel plate and the single-layer color steel plate roof. In the construction process, the tapping force is too heavy and light, and the self screw is biased and skewed, etc., which may cause the self tapping rubber gasket to deform, fall off or form concave surface, causing the roof drip water leakage and accumulate through the heat preservation cotton, accumulating more and more, forming multi-point water leakage. In addition, the position of self tapping wire is not right, and the purlin under the color steel plate is missed to form holes directly, which is also one of the important reasons for water leakage. This kind of water leakage may not be obvious in the roof structure of single-layer color steel plate without thermal insulation system, mainly because the rainwater is directly dispersed after leakage through the contact part of steel plate and purlin, and does not necessarily drip rapidly.
2. Water leakage at the joint of color steel plate
The horizontal and vertical lap joints and the lap joints of color steel plates leak. If the tile wave of color steel plate is too low or the rain water is too large to pass the tile wave, it is easy to form a large area of water leakage, and it is not easy to detect the water leakage point. Once formed, it is not easy to repair, which is often seen in the arc roof. The main reasons are that the lap between the two plates is not tight, and the self tapping wire is not full to form a gap, etc.
3. Roof tiles leaking
In the construction of light steel structure roof, water leakage caused by roof ridge tile is also a common phenomenon. In rainy season, especially when there is a large amount of rain, the splash of rain water passes through the joint of two color steel plates at the lower part of the ridge tile, forming a large area of leakage.
After understanding the structure of color steel sheet roof, possible leakage points and causes of water leakage, we will talk about the treatment plan. Based on years of construction experience, two leakage schemes are proposed:
1. Waterproofing of the whole roof
This scheme can make the color steel sheet roof form a whole connected waterproof layer, and self-adhesive membrane is recommended for urban waterproofing. Self adhesive roll is a kind of waterproof and sealing material which can be bonded with the base surface by itself. It can be divided into two types: self adhesive with tire and self adhesive without tire. There are tire self-adhesive upper and lower self-adhesive intermediate clamping tire bases, the upper covering is vinyl film, and the lower covering is peelable silicone oil film. Tire free self-adhesive is composed of self-adhesive, upper vinyl film and lower silicone oil film. The product has self-healing property, that is, when the coil is punctured or embedded with hard objects, it will automatically integrate with these objects, and still can maintain good waterproof performance. See: self adhesive rubber asphalt waterproof roll for product details
2. Waterproof treatment shall be carried out for roof screws and fasteners, color steel plate lap joint and roof ridge tile. The construction process is: cleaning the base course → brushing the base course to treat the waterproof material → construction of additional reinforcement layer → brushing the waterproof coating.
The above two schemes can effectively control the water leakage of color steel sheet roof. The specific selection can be judged according to the construction area and other factors.