Prefabricated House Gap Treatment

The treatment of gaps in prefabricated houses requires selecting appropriate methods based on the location, type, and severity of the cracks. Details are as follows:

1. Treatment of Common Cracks in Prefabricated Panel Buildings
If the cracks are non-structural and common, the adhesive reinforcement method can be used: First, fill the interior of the gaps with filling materials (such as cement mortar) to ensure there are no voids; then, paste Dacron cloth or mesh cloth on the crack surface to enhance crack resistance; finally, cover with carbon fiber cloth to improve overall structural stability. This method is suitable for scenarios where the crack width is small and there is no risk of leakage. During operation, ensure that the filling material is dense and the粘贴 (pasted) layer is flat without bubbles.

2. Repair of Horizontal Cracks

• Minor Cracks: If the number of cracks is small, the width is narrow, and there is no liquid leakage, they can be left untreated temporarily, but regular observation is required to check for expansion.
• Leaking Cracks: Immediate repair is necessary. The steps are as follows:
  • Chiseling the Gap: Chisel open the panel gap along the direction of the crack, removing 5 cm of the surface layer on both sides to make the joint surface slope-shaped, and chisel the surface and sides of the prefabricated panel to enhance bonding strength;
  • Cleaning the Base Layer: Use high-pressure air or a vacuum cleaner to remove debris and dust;
  • Applying Cement Slurry: Brush a layer of pure cement mortar (water-cement ratio 0.4-0.5) inside the panel gap;
  • Layered Pouring of Fine Aggregate Concrete: Pour for the first time to half the depth of the panel gap, and after absorption, pour for the second time to 1 cm from the panel surface, compacting and leveling;
  • Curing: After repair, cure for at least 2-3 days, during which stepping or loading is strictly prohibited.
    Note: Avoid drilling holes in the prefabricated panel to prevent damage to the load-bearing structure; if a ceiling is required, the hanging rod should be installed in the gap between two panels.

3. Waterproofing Treatment of Prefabricated Panel Houses
To prevent leakage, follow these steps:

• Cleaning the Gap: Use a vacuum cleaner to thoroughly remove dust and debris from the gaps in the prefabricated panels;
• Filling and Leveling: Use special tile adhesive to fill the gaps and level them, ensuring there are no depressions;
• Applying Waterproofing Agent: After the adhesive dries, evenly apply a waterproofing agent to cover all gap areas;
• Drying and Construction: After application, dry until the waterproof layer is completely cured before proceeding with subsequent decoration.

4. Treatment of Cracks at the Top or Joints
If the cracks are located on the roof prefabricated panels or joint areas, a professional construction team can be hired to operate:

• Widening the Crack: Use tools to widen the crack to a few millimeters;
• Filling with Putty: Fill the crack with putty and scrape it flat;
• Applying Anti-Crack Tape: Paste anti-crack tape on the putty surface to enhance tensile strength;
• Second Putty Application: Apply another layer of putty over the tape to ensure a flat surface.

5. Treatment of Ceiling Cracks in Old Houses
Ceiling cracks in old houses are often caused by joints in the prefabricated panels and require re-plastering:

• Dust Removal: Remove loose cement and dust from the joint area;
• Plastering Operation: Use high-strength cement mortar to complete the plastering in one go, avoiding re-cracking at the joints between new and old cement;
• Curing: After plastering, keep the environment moist to promote cement hardening.