Conversion of Rural Tiled Roofs to Prefabricated Panels

In the past, it was relatively common to replace rural tiled roofs with prefabricated panels, but there are many drawbacks. If economic conditions permit, cast-in-place concrete roofs are a better choice; if prefabricated panels are to be used, their drawbacks must be accepted and addressed.

1. Prominent Waterproofing Issues
   Prefabricated panels are prefabricated components that require filling with mortar or concrete during assembly. However, factors such as material shrinkage and construction errors can lead to cracks at the joints. According to statistics, the probability of rain leakage in prefabricated panel roofs is relatively high, with some even saying that '8 out of 10 households experience rain leakage.' Even with waterproofing measures (such as laying waterproof membranes or applying waterproof coatings), it is difficult to completely eliminate leakage. Usually, the waterproofing effect can only be confirmed after testing during the rainy season, and some projects even delay settlement of fees due to this issue.

2. Poor Earthquake Resistance
   Prefabricated panels adopt a spliced structure, with the panels only fixed to each other through local connections (such as steel bar anchoring or mortar filling), resulting in low overall stability. In earthquake-prone areas, this structure is prone to joint fractures or overall collapse due to seismic waves, posing serious safety hazards. In contrast, cast-in-place concrete roofs form a continuous structure through integral pouring, with significantly better earthquake resistance than prefabricated panels.

3. Insufficient Thermal Insulation and Sound Insulation
   Prefabricated panels are typically 12 centimeters thick and mostly hollow structures, with weak heat insulation in summer and thermal insulation in winter. To improve this defect, additional thermal insulation materials such as cinder or lime need to be covered on the panel tops during construction, which increases costs and construction complexity. Additionally, the hollow structure easily transmits sound, resulting in poor sound insulation and affecting indoor comfort.

4. Other Potential Defects
   Some low-quality prefabricated panels may have reduced load-bearing capacity due to missing steel bars or insufficient concrete strength, posing structural safety risks. At the same time, prefabricated panels are relatively heavy, requiring high load-bearing capacity from the original house walls. If the walls are aged or inadequately designed, it may lead to wall cracking and other issues.

Improvement Suggestions: If prefabricated panels are to be used, waterproofing measures should be strengthened (such as using double-layer waterproof membranes), earthquake-resistant structural measures should be added (such as adding ring beams or structural columns), and thermal insulation materials should be covered to improve thermal performance. However, overall, cast-in-place concrete roofs are still a more recommended alternative due to their good integrity, strong earthquake resistance, and long-lasting waterproofing.