How to Prefabricate House Eaves

The prefabrication of house eaves requires operation in accordance with standardized procedures, with a focus on controlling technical, material, construction, and acceptance aspects. Details are as follows:

I. Construction Preparation

1. Technical Preparation:

   • Organize a drawing review to verify the dimensions of eave components, the construction of anchor nodes, drainage slopes (≥2%), and methods for handling waterproof nodes. Based on the on-site structural dimensions, conduct detailed design to clarify component numbers, installation sequences, and locations of reserved holes.
   • Prepare technical disclosure documents specifying installation accuracy (axial deviation ≤3mm, elevation deviation ±5mm), welding parameters (E43 welding rods, current 100-140A), waterproofing procedures, and acceptance criteria. Ensure process execution through three-level technical disclosures.

2. Material Preparation:

   • Prefabricated Components: Use C30 concrete eave panels with built-in φ8mm HRB400 steel mesh (spacing 150mm×150mm). Provide compressive strength reports (≥30MPa) and structural performance test reports upon delivery. Ensure surfaces are flat, corners are undamaged, and embedded parts have deviations ≤10mm.
   • Auxiliary Materials: Select 4mm thick SBS modified asphalt waterproof membranes (polyester base) for waterproofing, along with matching base treatment agents and sealants (weather resistance ≥20 years). Welding materials include E43 welding rods and φ10mm galvanized metal straps. Use epoxy resin construction adhesive (tensile bond strength ≥3.0MPa) for structural bonding. Other materials include polymer cement mortar (crack resistance P8) and eagle-beak drip moldings (15mm×10mm).

3. On-site Preparation:

   • Surveying and Layout: Mark control lines for overhang dimensions (deviation ±10mm), side lines (straightness ≤5mm/2m), and elevation control lines (points set every 5m). Chisel out and straighten reserved anchor rebars in the main structure (diameter ≥φ12mm, exposed length ≥30d).
   • Base Treatment: Clean the installation surface and level it with 1:3 cement mortar (flatness ≤5mm/2m). Round internal and external corners with a 50mm radius. After drying, apply a base treatment agent (0.2kg/㎡) and cure for ≥4h.
   • Temporary Support: Erect a full-hall scaffold (post spacing 1.2m×1.2m, crossbar spacing 1.5m) with adjustable top jacks (bearing capacity ≥10kN). Lay 50mm thick wooden planks and conduct a load test with 1.2 times the component's self-weight, holding for 1h without settlement.

II. Construction Process
Surveying and layout → Base treatment → Mortar bedding → Prefabricated component hoisting → Position correction → Welding and anchoring → Temporary fixation → Waterproofing → Drip molding installation → Acceptance.

III. Key Operation Points

1. Mortar Bedding: Use 1:2 dry-hard cement mortar (water-cement ratio 0.5) with a thickness of 20mm, extending 50mm beyond the component edges. Apply a plain cement paste bonding layer before laying and complete component installation within 30min.
2. Component Installation: Hoist prefabricated eaves according to design requirements, ensuring firm connection with the roof. Correct the position and weld anchor rebars, using temporary fixation measures to prevent displacement.
3. Waterproofing: Apply waterproof coating evenly without omission and fill joints with sealant to ensure proper sealing.

IV. Quality Control
Materials must comply with national standards, and construction must strictly follow the process. Acceptance should be based on national and local regulations, with a focus on inspecting installation accuracy, welding quality, and waterproofing effectiveness.