How to Identify Prefabricated Panel Houses

To determine whether a house is a prefabricated panel house, a comprehensive analysis can be conducted using the following methods:

1. Observe the Construction Year
Prefabricated panel houses are mostly concentrated in residential buildings constructed during specific historical periods. According to industry experience, commercial housing built after 2003 generally uses cast-in-place slab structures, while older houses built before 2003, especially those before 1998, often use prefabricated panels due to the limitations of construction technology at the time. If the house was built during this period, further verification is needed in combination with other characteristics.

2. Examine the Physical Characteristics of the Floor Slab

• Crack Patterns: The floor slab of a prefabricated panel house is composed of multiple prefabricated components joined together, often resulting in regular parallel cracks on the ceiling, distributed in a blocky manner with visible gaps between the panels. In contrast, the cast-in-place slab, being poured as a whole, tends to have irregular cracks with a smooth and flat surface and no obvious joint marks.
• Knocking Sound and Vibration Transmission: When lightly tapping the floor slab with a hard object, the prefabricated panel will produce a clear 'ding-ding' sound with a long echo, and the vibration will transmit only in a single direction. The cast-in-place slab, due to its strong structural integrity, will produce a dull sound with vibrations spreading in all directions.

3. Inspect the Wall Structure
Prefabricated panel houses, due to their lower load-bearing requirements, typically have no obvious beam-column structures in the walls, relying solely on the prefabricated panels for support. In contrast, cast-in-place slab houses often have reinforced concrete beams and columns incorporated into the walls to enhance overall stability. If large beams and columns are visible inside the house, it is likely a cast-in-place structure.

4. Look for Characteristic Holes in the Floor Slab
Some prefabricated panels are manufactured with circular holes approximately 8 centimeters in diameter (used to reduce weight or for wiring). If such regular holes are present on the surface of the floor slab, it can be preliminarily determined to be a prefabricated panel.

5. Check the Original Design Drawings
If the original design drawings of the house can be obtained, the type of floor slab structure can be directly identified from the annotations. Drawings that clearly indicate 'prefabricated panel' or 'assembled floor slab' refer to prefabricated panel houses, while those indicating 'cast-in-place slab' or 'reinforced concrete monolithic pouring' refer to cast-in-place structures.

Precautions:

• A single characteristic may have errors, so a comprehensive judgment should be made by combining multiple methods. For example, some older houses may have their original structural features concealed due to renovations, requiring careful analysis.
• If identification cannot be confirmed through observation, it is recommended to contact a professional agency for structural testing to obtain an accurate conclusion.