Prefabricated Roofing Material for Flat Houses

Prefabricated roofing for flat houses offers the advantages of low cost and fast construction, but it has defects such as weak overall rigidity, susceptibility to cracking and leaking, poor earthquake resistance, and insufficient insulation. Its lifespan requires professional assessment, and regular maintenance is necessary to extend its service life.

Composition and Construction Characteristics of Prefabricated Roofs

Prefabricated roofs are made in advance from crushed stone, cement, sand, and coiled wire (or cold-drawn wire) and are produced in factories to form standardized components. Their core advantage lies in high construction efficiency, as they can typically be hoisted and installed in a day or half a day, significantly shortening the construction period. Additionally, they are cost-effective, with lower material and labor costs compared to cast-in-place roofs, making them suitable for projects with limited budgets.

Performance Defects of Prefabricated Roofs

1. Weak Overall Rigidity: Prefabricated panels are made in sections and connected with concrete or mortar between them, resulting in poor overall integrity. When the foundation experiences uneven settlement or encounters geological disasters (such as earthquakes or landslides), cracks are prone to appear at the connections, leading to water leakage.
2. Low Earthquake Resistance: The connection strength between prefabricated panels and the load-bearing structure is limited. In earthquake-prone areas, seismic waves can easily cause the panels to detach or the entire structure to collapse, posing a high safety risk.
3. Insufficient Insulation: The thermal insulation performance of prefabricated panels is poor. The interior tends to be stuffy in summer and lacks warmth in winter. Usually, additional covering materials such as cinder or lime or the installation of an insulation layer are required to improve the situation.

Lifespan Assessment and Policy Requirements

According to housing safety appraisal standards, the lifespan of prefabricated panel houses is not fixed at 30 years but needs to be determined through professional agency assessment:

• Grade A, Grade B: Structurally safe and can be used normally;
• Grade C: Requires local reinforcement (such as repairing cracks and strengthening connections);
• Grade D: Requires immediate demolition.
  The 2026 policy clearly stipulates classified governance for Grade C and Grade D prefabricated panel houses, prioritizing the demolition of Grade D dilapidated houses and promoting seismic reinforcement projects.

Daily Maintenance Recommendations

To extend the service life of prefabricated roofs, the following items need to be inspected regularly:

1. Panel Joints: Observe for cracks or water seepage, promptly repair them, and reapply a waterproof layer;
2. Load-Bearing Structure: Check for deformation or cracking in beams and columns and avoid overloading;
3. Usage Specifications: Prohibit randomly cutting holes in the roof or stacking heavy objects to prevent structural damage.

Through scientific assessment and regular maintenance, prefabricated roof houses can extend their service life under safe conditions, but their suitability needs to be weighed according to actual conditions.