1. Pre-installation Preparation: Ensure Structural Compatibility
Check the flatness of the roof purlins (supporting structure). The error should be controlled within ±5mm to prevent uneven stress and subsequent deformation of the panels due to an uneven foundation.
Confirm that the panel specifications match the design (e.g., length, thickness, overlap width), and prepare matching fasteners (e.g., self-tapping screws, elastic clips). The screws must have an anti-corrosion coating (e.g., galvanized, aluminum-zinc plated).
2. Core Installation: Focus on Sealing and Deformation Resistance
Overlap Sealing: The horizontal overlap width should be ≥100mm. The vertical overlaps must be aligned and filled with special sealant (e.g., butyl rubber sealant) to prevent rainwater infiltration. For high-risk areas (e.g., roof ridges, eaves), additional waterproof tape can be applied.
Expansion Joint Reservation: Due to the high thermal expansion and contraction coefficient of metal, an expansion joint (width 10-20mm) should be set every 10-15 meters. Meanwhile, sliding elastic clips should be used to avoid arching and cracking of the panels when they expand due to heat.
3. Fixing Specifications: Avoid Damage and Loosening
Fastening screws must be driven vertically into the purlins; tilting is strictly prohibited (to prevent damage to the panel coating and water seepage). The screw spacing should be uniform (usually 300-500mm horizontally, set along the purlin spacing vertically) to avoid panel sagging caused by excessive spacing.
Handle the panels gently during installation; avoid dragging to prevent scratches on the surface coating (coating damage will accelerate corrosion). If there are scratches, touch them up with matching repair paint in a timely manner.
4. Detail Handling: Cover High-Risk Areas
Install water deflectors at the eaves to prevent rainwater from flowing back along the eaves. Use special ridge covers to cover the roof ridges, with the cover overlapping the panels by ≥150mm on both sides and ensuring proper sealing.
For roof openings (e.g., smoke vents, pipe openings), first install special waterproof flanges, then cut the panels to fit over them, and fill the gaps with sealant to avoid water leakage at the openings.