Question 1: What are the commonly used lighting and ventilation materials?
Main lighting materials: The mainstream choices are FRP (fiberglass reinforced plastic) skylights and PC (polycarbonate) sun panels, each with its own characteristics.
FRP skylights: Made of fiberglass and unsaturated resin, they offer high cost-effectiveness and can be customized to match the waveform of color steel panels, allowing for easy overlapping installation along slopes. Their coefficient of thermal expansion is similar to steel, reducing the risk of gaps and leaks caused by temperature differences.
PC sun panels: Made with polycarbonate as the base material, they offer stronger impact resistance, and their hollow structure provides superior thermal insulation. Light transmittance can reach approximately 88%, but their coefficient of thermal expansion is relatively high, requiring expansion joints during installation.
Main ventilation equipment: Primarily includes two types: natural ventilators (louvers) and motorized skylights for lighting and smoke extraction.
Natural ventilators (louvers): Rely on thermal pressure and wind pressure to achieve continuous air exchange with zero energy consumption. Based on their shape, they can be divided into two types: streamlined (large throat, large ventilation volume) and thin (low height, good wind resistance).
Electric skylights for lighting and smoke extraction: These combine lighting, ventilation, and fire-fighting smoke extraction functions, can be opened as needed, and have a high degree of automation.
Question 2: How to choose the right material combination for different environments?
Material selection strategies should be tailored to local conditions. Here are some classic combination solutions:
Application Environment | Recommended Combination | Combination Advantages
Ordinary Indoor/General Factory Buildings | Aluminum-zinc coated steel sheet + FRP translucent panel | A durable combination with excellent cost performance. The FRP panel provides soft light transmission, suitable for general environments, meeting basic lighting and ventilation needs.
Hydraulic/Slightly Corrosive Environments | Aluminum alloy outer cladding + PC polycarbonate sheet | Aluminum alloy has excellent rust resistance, and the PC polycarbonate sheet is impact-resistant and provides insulation, suitable for workshops with high environmental requirements, such as food processing plants.
Chemical/Coastal Highly Corrosive Environments | Stainless steel outer cladding + Corrosion-resistant FRP translucent panel | Stainless steel has a corrosion resistance of over 15 years, combined with chemically resistant FRP panels, providing protection against harsh environments from the outside in.
Question 3: What are the most critical operational points during installation?
Improper installation is a major cause of leaks and damage. The following points require special attention:
**Compliance with Corrugated Steel Sheets:** The overlap length between the skylight and the roof along the slope must be no less than 250mm to effectively prevent leakage caused by "wind pressure backflow." The overlap length of the corrugated steel sheet itself should also be ≥200mm.
**Proper Sealing:** The overlap area must be fully coated with weather-resistant sealant, with a thickness of no less than 2mm. Fasteners must use self-tapping screws or rivets with waterproof washers, and the design spacing must be strictly adhered to.
**Suitable Sheet Selection:** In areas with strong winds, the skylight thickness should not be less than 1.5mm, and the steel edge trim thickness is recommended to be ≥1.2mm, with a tensile strength ≥125MPa. In coastal or chemical industrial areas, it is recommended to use FRP skylights with an anti-corrosion coating and double-corrosion-resistant steel edge trim. Note: The recommended thickness of the main color-coated sheet for ordinary roofs is 0.8-1.2mm, depending on the specific location.
Proper preparation is essential: Cutting should be done on a clean surface, and edges should be sanded to reduce burrs; before installation, check the coating condition of accessories, and promptly reapply anti-corrosion paint to any scratches or damage.
Question 4: How to Choose a Ventilator? What Materials Are Available?
Ventilators are key equipment, mainly composed of several systems: the outermost barrier, the frame support, and the transmission control. Different grades of materials can be selected based on the environment.
Structural Components | Material Options | Features and Applicable Scenarios
Outer Shelf / Rainproof Sheet | Aluminum-zinc coated steel sheet (commonly 0.5-0.6mm)
Stainless Steel / Aluminum Alloy Sheet
FRP (Fiberglass Reinforced Plastic) Translucent Panel | Preferred material. Aluminum-zinc coating ≥150g/m² on both sides ensures long-term corrosion resistance and acts as a rain barrier. Stainless steel or aluminum alloy is selected for highly corrosive environments. FRP can also be used for the rainproof panel, providing light transmission functionality.
Frame | Hot-dip galvanized steel
Aluminum Alloy / Stainless Steel | Core load-bearing structure; its strength and corrosion resistance are crucial. Commonly used are 1.2mm or 1.5mm thick hot-dip galvanized steel sheets.
Question 5: How to structurally prevent the "nine out of ten roofs leaking" problem?
Leaking is a common problem with precast concrete roofs and must be prevented through design and construction.
Optimize waterproofing design: Choose products with "structural waterproofing" design, avoiding components that rely solely on silicone waterproofing. For equipment such as ventilators, use factory-prefabricated integrated waterproof bases for rigid connection to the roof panels.
Strictly handle overlaps and joints: Apply a continuous sealant to overlaps before connecting them with self-locking rivets spaced 100-150mm apart. For skylights, a continuous sealant must also be applied between the dedicated steel side and the skylight panel.
Use high-quality sealing materials: Where possible, prioritize butyl rubber sealing tape or apply two coats of weather-resistant sealant to critical areas to maximize sealing performance.