Category: high quality PPGI corrugated roofing sheet
By Alisajpq, 2019-03-20
1. "Technical Regulations for Steel Structures of Lightweight Houses with Portal Frames" stipulates: The slope of the roof of light-weight houses should be 1/8~1/20, and the larger value should be taken in areas with more rain. In the actual design project, due to the small slope of many engineering roofs, the rainwater on the high quality PPGI corrugated roofing sheet could not be discharged into the gutters in time, which caused the water in the house to cause water seepage. 2. The designer's lack of understanding of the rainfall location of the project site is also an important factor causing the design of the roof slope to be too slow and the cross-section of the gutter to be too small. At present, in China's steel structure design, different waterproof measures are adopted without considering regional climate differences. 3. At present, most of the steel structure design drawings lack nodes and large-scale design drawings. The flooding edging is controlled by the construction unit at random. The roof is narrow and the height of the parapet is not enough. The position of the device is not proper or the height is not enough, which may affect the construction of the waterproof layer of the roof panel. It is easy to cause water seepage in these parts. 4. The design of the roof panel holes is not considered well. Try not to cut holes at the construction site, and it is difficult to make holes in the hole.
By Alisajpq, 2019-03-14
Under the high quality PPGI corrugated roofing sheet and the wall surface, the glass fiber mat is usually used for insulation. If the steel sheet and the fiber mat are in contact, the moisture absorption under the film will occur, especially near the end of the fixed plate steel plate and the color coated plate under the eaves. Submembrane corrosion occurs. Therefore, the insulating felt should be mounted on the fixed backing plate to keep it dry to avoid the occurrence of capillary phenomenon and under-film corrosion.
Similarly, if the insulating felt on the roof and upper wall is improperly installed, it will cause corrosion on the back side of the high-quality PPGI corrugated roofing sheet under the action of condensation and wind and rain. During the installation process, the insulating felt should be protected from continuous moisture. The correct roofing sheet insulation felt installation method should seal all the sealing film joints, repair all the holes and other defects on the sealing film to avoid water seepage because the water vapor condensation on the back of the roofing sheet panel Absorbing moisture with the insulating film will cause under-film corrosion.