Views: 0 Author: Site Editor Publish Time: 2026-07-04 Origin: Site
Project Background: The Leakage Nightmare
In early 2026, a 10,000m² logistics warehouse in Shandong was facing severe roof problems. The existing single-layer metal roof had degraded over 8 years, causing:
Water leakage during heavy rain, damaging stored goods worth over ¥500,000 annually
Heat loss in winter, with energy bills 40% higher than design specifications
Condensation on the underside, leading to rust and mold
The warehouse needed a complete roof replacement within 25 days to avoid business interruption. After evaluating multiple solutions, the facility manager chose sandwich panel roofing sheets from Glostar New Materials.
Why Sandwich Panel Roofing Sheets?
The metal roof sandwich panel (also known as insulated roofing sheets or PU sandwich panel roof) consists of two metal facings bonded to a rigid foam core. Glostar’s PU sandwich panel roof offers the following certified performance:
Parameter | PU Sandwich Panel Roof (Glostar) | Previous Single-Layer Metal Roof |
|---|---|---|
Thermal conductivity | ≤0.022 W/m·K | 0.058 W/m·K |
Fire rating | B1 (flame retardant) | B2 (combustible) |
Water absorption | ≤2% | ≥8% (through joints) |
Load capacity | ≥1.5 kN/m² | ≥0.8 kN/m² |
Installation speed | 150 m²/man/day | 60 m²/man/day |
The rock wool roof panel version was also considered for higher fire resistance, but the client prioritized thermal performance and cost-efficiency, so the PU sandwich panel roof was selected.
Solution Design: Full Roof System
Glostar’s technical team designed a complete prefabricated roof panel system:
Panel specification: 100mm thick sandwich panel roofing sheets with galvanized steel facings (0.6mm top, 0.5mm bottom), polyurethane foam core.
Joint system: Cam-lock hidden fastener design, with pre-applied butyl sealant for airtightness.
Flashings & accessories: Custom ridge caps, eaves flashings, and gutter systems made from matching pre-painted steel.
Insulation continuity: All joints were sealed with expanding foam to eliminate thermal bridges.
Installation Process: 20 Days to Completion
Day 1-2: Demolition of old roof, surface cleaning, and structural reinforcement.
Day 3-12: Installation of metal roof sandwich panel – panels were lifted by crane and locked into place using the cam-lock system. Each panel was aligned with laser guides to ensure straightness.
Day 13-16: Flashing installation, ridge capping, and gutter fitting.
Day 17-18: Sealant application and final inspection of all joints using infrared thermography to detect air leaks.
Day 19-20: Commissioning – water spray test, thermal imaging survey, and client sign-off.
Key Data:
Total panel area: 10,200 m²
Panel waste rate: <1.5% (factory pre-cut to exact lengths)
Installation crew: 12 workers
Average daily output: 510 m²
Results: Zero Leakage, 35% Energy Savings
After 6 months of operation, the warehouse reported:
Leakage: Absolutely zero, even during typhoon-level rainstorms.
Energy consumption: Reduced by 35% compared to the old roof, saving ¥280,000 annually.
Temperature stability: Interior temperature remained within ±2°C of setpoint, vs ±5°C before.
Condensation: No condensation observed on the underside, thanks to the closed-cell foam core.
Customer Feedback
Mr. Zhang, the warehouse operations manager, commented:
“The sandwich panel roofing sheets from Glostar completely solved our leakage problem. The installation was incredibly fast – we were back in business in just 20 days. The energy savings alone will pay for the investment in less than 3 years. We’re now planning to use the same metal roof sandwich panel for our other facilities.”
Conclusion: Why Sandwich Panel Roofing Sheets Are the Future
For any industrial or commercial roof replacement, sandwich panel roofing sheets offer the best combination of thermal performance, moisture resistance, and installation speed. Glostar New Materials provides a full range of insulated roofing sheets, from PU sandwich panel roof to rock wool roof panel, backed by CNAS lab data and over 20 years of industry experience.
