Is It Good to Use Prefabricated Panels for Flat House Roofs?

Prefabricated panels can be used for flat house roofs, but they are not recommended. Here is a detailed analysis:

Advantages:

1. Low cost: Prefabricated panels have a significant price advantage. For a roof area of 40 - 50 square meters, the material cost is only 800 to 1000 yuan, which is more than half cheaper than a cast-in-place concrete roof. This feature is highly attractive to users with limited budgets.
2. Efficient construction: Prefabricated panels are produced in a standardized factory setting. On-site installation only requires crane operations, and the roof can be laid in half a day, significantly shortening the construction period. This characteristic is especially suitable for projects with tight construction time requirements.

Disadvantages:

1. Poor waterproof performance: The joints of prefabricated panels are prone to becoming leakage隐患 (potential leakage points). In actual use, the probability of rain leakage is relatively high. Data shows that '8 out of 10 households experience rain leakage'. Long-term leakage may lead to damage to the roof structure and increase later maintenance costs.
2. Weak earthquake resistance: Prefabricated panels are assembled structures with poor integrity and a low seismic coefficient. Their use has been explicitly prohibited in earthquake-prone areas. Even in non-seismic zones, their deformation resistance is much weaker than that of cast-in-place roofs, posing safety hazards.
3. Poor thermal insulation performance: The material of prefabricated panels has high thermal conductivity. In summer, the indoor temperature rises significantly, and in winter, heat dissipates quickly, resulting in a large indoor temperature difference. Additional thermal insulation layers or air-conditioning equipment are required, indirectly increasing usage costs.
4. Insufficient structural integrity: Prefabricated panels are installed by splicing, and the joints are prone to cracks due to settlement or temperature changes, further exacerbating the risk of leakage and making it difficult to completely solve the problem through simple repairs.

Suggestions:
If the budget allows, a cast-in-place concrete roof is a better choice. A cast-in-place roof forms a seamless structure through integral pouring, with superior waterproof, earthquake-resistant, and thermal insulation performance compared to prefabricated panels, and a longer service life. Although the initial cost is higher, the long-term maintenance cost is low, and the overall cost-effectiveness is better. For users with a tight budget and in non-seismic zones, if prefabricated panels are selected, strict joint waterproofing treatment should be carried out, and a maintenance budget should be reserved.