Construction Method for Flat Roofs of Prefabricated Panel Houses

The construction method for flat roofs of prefabricated panel houses mainly includes steps such as prefabricated panel production, roof laying, and insulation layer installation, but it is important to note some structural defects that may exist.

Prefabricated Panel Production

Prefabricated panels are pre-made in factories or on construction sites using materials such as crushed stone, cement, sand, and coiled rods (or cold-drawn wires). Crushed stone serves as the aggregate, enhancing the strength and stability of the panels; cement acts as the main binding material, holding all components together; sand fills the gaps, improving density; and coiled rods or cold-drawn wires function as reinforcement, increasing the tensile strength of the panels. During production, these materials are mixed in specific proportions, poured into molds, and compacted. After curing to achieve a certain strength, the prefabricated panels are ready for use.

Roof Laying

When constructing the roof, prefabricated panels are placed directly on the brick walls of the house and pieced together one by one. During the assembly process, concrete or cement mortar is used to fill and bond the gaps between the panels to ensure a secure connection. However, this laying method has some issues. Since the prefabricated panels and the walls are not an integrated structure, they lack effective connection and fixation, failing to provide tensile and stabilizing effects. Additionally, gaps are prone to appear at the joints, allowing rainwater to seep into the house during rainy weather, affecting normal use. Furthermore, when the foundation settles, cracks can easily form between the prefabricated panels and between the panels and the walls, exacerbating the leakage problem and potentially even affecting the structural safety of the house.

Insulation Layer Installation (Optional)

In the installation of insulation layers for flat roofs, if the method of suspending prefabricated panels to create an air gap is used, a "cold roof insulation system" can be formed. Specifically, an air gap is created between the waterproof layer and the insulation layer. This prevents the heat from indoor heating from directly affecting the roof waterproof layer, effectively reducing heat loss and improving the insulation performance of the house. However, this insulation system requires high construction techniques to ensure the airtightness and stability of the air gap; otherwise, the insulation effect will be compromised.