Prefabricated Panels for Sloped Roofs of Houses
The use of prefabricated panels for sloped roofs was once relatively common in rural self-built houses, but it has numerous drawbacks. Current building codes have phased out this practice, and if it must be used, strict adherence to construction specifications is required.
Poor Seismic Performance: Prefabricated panels are directly placed on walls without the restraint of ring beams and structural columns. During an earthquake, the house is subjected to horizontal shaking forces, and the prefabricated panels are prone to displacement due to these horizontal forces, leading to collapse. For example, in a case where a sloped roof used 5-hole prefabricated panels with only horizontal fixation at the ends, this simple fixation method could not effectively resist seismic forces, posing a risk of sliding and seriously threatening the lives of occupants.
Prominent Waterproofing Issues: During the assembly of prefabricated panels, gaps exist between the panels. These gaps are clearly visible and allow light to pass through. Even if cement is applied later for gap filling, it is difficult to completely solve the problem of rain leakage. According to relevant statistics, the rain leakage rate of rural houses with prefabricated panel roofs is as high as 80%. This not only affects the normal use of the house but may also cause damage to the interior decoration and items.
Insufficient Thermal Insulation: The thickness of prefabricated panels is usually about 12 centimeters, and they have a hollow structure. This structure cannot effectively block the transfer of heat. In summer, outdoor high temperatures can easily enter the interior, raising the indoor temperature; in winter, indoor heat quickly dissipates, causing the indoor temperature to drop. To improve this situation, additional materials such as cinder are often required to cover the panels to compensate for their thermal insulation deficiencies, increasing usage costs and construction complexity.
Low Structural Safety: Some construction units, in order to save costs, even omit the construction of inter-story ring beams. Inter-story ring beams play an important role in enhancing the overall stability of the house. Omitting them makes the house structure more fragile and further weakens the house's resistance to natural disasters or other external forces.
Current building codes have phased out prefabricated panel roofs and recommend the use of cast-in-place reinforced concrete structures. Although the cost of cast-in-place reinforced concrete structures is relatively high, they can significantly improve the seismic, waterproof, and thermal insulation performance of the house. If the use of prefabricated panels is necessary due to budget constraints, strict construction specifications must be ensured, such as adding ring beams and strengthening joint waterproofing treatments, to reduce safety risks.
