When the single slope length is less than 12M, the roof can not be set with transverse joints; when the slope length of one side is greater than 12M, transverse joints should be set between color steel plates. The transverse joints are generally overlapped along the water. To ensure the waterproof effect, a certain lap length must be met, and the length of the lap length is related to the roof slope. When the slope is less than or equal to 1 / 10, it should not be less than 300 mm; when the slope is greater than 1 / 10, it should not be less than 200 mm. The height of the lap joint should be staggered, and the waterproof sealant strip should be pasted between the upper and lower plates. This can not only effectively prevent water seepage, but also prevent oxidation and corrosion of steel plate incision. At the same time, it should be noted that the lap joint is generally fixed in the wave crest position with self tapping screws. If it is set on the trough, reliable waterproof measures must be taken.
Roof low wave color steel plate is directly connected with purlin by connectors, one for each wave or every other wave, but connectors must be set at overlapping wave. The roof high wave color steel plate is connected with the fixed support by connecting pieces, one for each wave. Another method of connecting the upper and lower plates is the pressing plate pressing method. A galvanized steel plate with the same type as the color steel plate is set at the top and bottom of the two color steel plates, and the waterproof sealing strip is set between the two plates, which are tightly squeezed together by the fastening bolts. In order to avoid water leakage caused by the long-term lap joint of the plate, the profiled plate production equipment can also be transported to the site for installation. The whole roof panel from the roof ridge to the cornice can be rolled and installed while rolling. There is no need for long-term lapping to avoid unnecessary leakage. In general, it is best to choose the long plate without overlapping, but it is found in the actual project that when the plate is too long, the expansion of screw hole will be caused due to the influence of temperature on the expansion of screw hole; at the same time, because the plate is too long, it is easy to damage the coating in the process of manufacturing, transportation or construction, and affect the quality.
