The 4mm polycarbonate sheet offers the perfect balance between strength, flexibility, and light transmission, making it an ideal choice for a wide range of industrial, commercial, and architectural applications. Thicker and more durable than 3mm sheets, yet lighter and easier to handle than 6mm options, the 4mm panel delivers reliable impact resistance, excellent thermal and UV protection, and long-lasting performance in both indoor and outdoor environments.
Widely used in roofing, skylights, greenhouses, partitions, and protective glazing, 4mm polycarbonate sheets provide clarity, durability, and cost-effectiveness for contractors, builders, and distributors seeking high-quality solutions.
At G-Crystal Plastic Industries, we manufacture and export premium 4mm polycarbonate sheets in bulk, made from 100% virgin material, customizable for size, color, and coating, serving businesses, importers, and distributors in over 60 countries worldwide.
What is a 4mm Polycarbonate Sheet?
A 4mm polycarbonate sheet is a medium-thickness, high-performance thermoplastic panel known for its strength, clarity, and versatility. Thicker than 2mm and 3mm sheets, it offers enhanced impact resistance, thermal insulation, and weather durability, making it suitable for both commercial and industrial applications.
These sheets are commonly used in roofing, skylights, greenhouses, protective panels, partitions, and façades, providing an ideal balance between lightweight handling and long-term structural performance. With optional UV coating and surface finishes like frosted, tinted, embossed, or twin-wall designs, 4mm polycarbonate sheets can be tailored to meet a wide range of project requirements.
Key Features of 4mm Polycarbonate Sheets
- Exceptional Impact Resistance and Structural Strength
4mm polycarbonate sheets are remarkably strong, offering impact resistance far superior to glass or acrylic. This makes them ideal for protective panels, safety glazing, roofing, and partitions, ensuring both durability and safety in demanding environments. - Advanced Thermal and UV Protection
These sheets provide effective thermal insulation, helping to maintain energy efficiency indoors. UV-coated variants protect against yellowing and degradation, making them suitable for prolonged outdoor exposure without compromising clarity or performance. - Superior Light Transmission and Clarity
With high transparency, 4mm sheets allow optimal natural light while maintaining clear visibility. Perfect for skylights, façades, greenhouses, and commercial spaces that require both illumination and aesthetic appeal. - Excellent Weather Resistance and Longevity
Engineered to withstand moisture, extreme temperatures, and harsh weather conditions, these sheets deliver long-term durability for both indoor and outdoor installations. - Lightweight, Flexible, and Easy to Handle
Despite their strength, 4mm sheets are lightweight and easy to cut, drill, or bend, simplifying installation and allowing creative architectural applications without sacrificing durability.
What Makes 4mm Polycarbonate Sheet So Popular?
The 4mm thickness strikes an ideal balance between flexibility and durability. It is light enough to be installed without heavy equipment, yet strong enough to resist impact, harsh weather, and daily wear. This makes it suitable for both DIY and commercial-grade installations.
Key Advantages:
- Impact Resistance: 200x stronger than glass
- UV Protection: Optional single or double-layer UV coatings
- Thermal Insulation: Especially in twin-wall format
- Weatherproof: No warping, corrosion, or yellowing
- Sustainable: Fully recyclable and ISO 14001 certified
- Lifespan: Up to 15+ years under outdoor exposure
Types of 4mm Polycarbonate Sheets
- Solid Clear: Transparent panels for maximum clarity and protection.
- Tinted: Colored sheets to reduce glare and enhance aesthetics.
- Frosted: Matte finish for privacy while allowing light diffusion.
- Embossed: Textured surface for decorative effects and diffused light.
- UV-Coated: Enhanced protection against UV rays for outdoor durability.
- Anti-Scratch: Hard-coated surfaces to resist abrasion, ideal for frequently handled panels.
- Twin Wall (Hollow) 4mm: Lightweight, thermally insulating sheets suitable for roofing, greenhouses, and partitions, providing strength while reducing material weight.
| Type | Description | Best For |
|---|---|---|
| Solid Clear Sheet | Transparent like glass, rigid and strong | Safety glazing, skylights, canopies |
| Twin-Wall Sheet | Hollow structure for insulation and weight reduction | Greenhouses, partitions, roofing |
| Embossed Sheet | Textured surface for privacy and glare control | Decorative walls, patio covers |
Sizes, Formats, and Customization
We manufacture 4mm polycarbonate sheets in global standard dimensions, with full flexibility for OEM and large projects:
| Specification | Options Available |
| Width | 1050 mm, 1220 mm, 2100 mm |
| Length | 6m, 12m, or any cut-to-size dimensions |
| Colors | Clear, Opal, Blue, Bronze, Green, Grey, or Custom RAL shades |
| UV Coating | Single side or double side |
| Special Finishes | Anti-fog, anti-scratch, crystal texture, DIVA embossing |
Use Cases of 4mm Polycarbonate Sheet
- Greenhouse and Agricultural Structures: 4mm twin-wall polycarbonate is widely used in agricultural greenhouses across Europe, Africa, and Latin America. It ensures optimal light diffusion, minimizes heat loss, and lowers energy usage — all while withstanding storms, moisture, and pests.
- Skylights and Roof Panels: G-Crystal’s 4mm solid and twin-wall sheets are perfect for skylights in industrial buildings, showrooms, and transportation terminals. They provide daylighting without compromising on strength or safety.
- Pergolas, Carports, and Outdoor Covers: The lightweight nature of 4mm sheets makes them ideal for residential and light-commercial roofs. Clear or opal sheets offer a modern aesthetic with sun and rain protection.
- Safety Glazing and Partitions: Solid 4mm panels are commonly used as impact-resistant glazing in schools, offices, and factories — a safer, lighter alternative to glass.
- DIY Projects and Signboards: 4mm polycarbonate is easy to cut, drill, and bend cold, making it ideal for display boxes, protective screens, and signage that must endure heat, UV, and repeated handling.
Thermal, Acoustic, and Environmental Performance
1. Thermal Performance
4mm polycarbonate sheets provide effective heat insulation, reducing indoor temperature fluctuations and enhancing energy efficiency. This makes them ideal for greenhouses, roofing, and partitions where maintaining a stable environment is important.
2. Acoustic Performance
The thickness and density of 4mm sheets help reduce noise transmission, offering improved sound insulation for offices, industrial spaces, and urban environments. While not as insulating as twin-wall designs, they still provide significant noise reduction compared to glass.
3. Environmental Performance
- UV Resistance: UV-coated 4mm sheets prevent yellowing and degradation under prolonged sunlight, ensuring long-term clarity.
- Durability: Resistant to moisture, extreme temperatures, and harsh weather conditions.
- Eco-Friendly: Made from 100% virgin polycarbonate, sheets are fully recyclable and engineered for a service life exceeding 15 years, supporting sustainable construction practices.
Installation and Recommended Accessories
We supply full installation support with every order. For 4mm polycarbonate sheets, we recommend:
- Framing: Aluminum or galvanized steel
- Sealing: Aluminum tape (top), vent tape (bottom)
- Joining: H-profiles and U-profiles for clean, watertight joints
- Fastening: Screws with rubber washers (do not overtighten)
- Slope: Install with a minimum 10° pitch to ensure drainage
All accessories are UV-stabilized and color-matched.36+
Real-World Project Example
A commercial garden center chain in Kenya installed 4mm opal twin-wall sheets across 4 retail greenhouses. After 18 months, they reported:
- 22% drop in HVAC energy costs
- No damage from seasonal storms
- Uniform crop and plant growth
Certifications and Global Export Support
G-Crystal Plastic Industries delivers 4mm polycarbonate solutions with international compliance:
- CE Mark for EU markets
- ISO 9001 – Quality Management
- ISO 14001 – Environmental Management
- ISO 45001 – Occupational Safety
We offer full FOB pricing, optimized container loads, export documentation, and multilingual support for distributors and wholesalers.
4mm Polycarbonate Sheet vs Acrylic and Fiberglass Sheets
When comparing clear materials at 4mm thickness, polycarbonate offers the best all-around performance compared to acrylic (PMMA) and fiberglass (FRP).
| Property | Polycarbonate | Acrylic (PMMA) | Fiberglass (FRP) |
|---|---|---|---|
| Impact Resistance | Very High (200× glass) | Moderate (15× glass) | Moderate |
| Light Transmission | 85–89% (UV-stable) | 92% (but yellows) | 70–80% (diffused) |
| UV Protection | Built-in | Limited | Poor |
| Flexibility | Cold-bendable | Rigid, cracks easily | Low |
| Lifespan | 15–20 years | 5–10 years | 3–7 years |
| Fire Resistance | Self-extinguishing | Flammable | Produces toxic fumes |
| Eco-Friendliness | Fully recyclable | Partially recyclable | Not recyclable |
Comparison Table: Polycarbonate Sheets by Thickness
| Thickness | Weight & Handling | Impact Resistance | Thermal Insulation | Applications | Cost |
|---|---|---|---|---|---|
| 2mm | Very lightweight, extremely easy to cut and install | Moderate, suitable for light-duty use | Low | DIY projects, indoor signage, partitions | Most cost-effective |
| 3mm | Lightweight, easy to handle | High, suitable for medium-duty applications | Moderate | Signage, protective glazing, roofing, indoor partitions | Balanced cost for performance |
| 4mm | Medium weight, manageable for manual installation | Very high, ideal for commercial and light industrial use | Good | Roofing, skylights, greenhouses, partitions, façades | Slightly higher than 3mm |
| 6mm | Heavier, requires more effort to handle | Extremely high, heavy-duty applications | Excellent | Industrial roofing, heavy-duty glazing, greenhouses | Highest cost due to material thickness |
Factors Affecting the Price of 4mm Polycarbonate Sheet
Several factors influence the price of 4mm polycarbonate sheets:
- Material Quality: Sheets made from 100% virgin polycarbonate are more expensive than recycled or blended alternatives.
- Surface Finish & Color: Clear, tinted, frosted, embossed, or UV-coated sheets have different costs depending on complexity.
- Protective Coatings: Anti-scratch, UV protection, or special treatments increase production cost.
- Quantity Ordered: Bulk purchases reduce unit price, offering better value for distributors and large projects.
- Customization: Special dimensions, colors, or finishes can affect pricing.
- Shipping & Export Terms: FOB pricing, logistics, and distance to the destination impact the final cost.
How to Cut 4mm Polycarbonate Sheets?
Cutting 4mm polycarbonate sheets is straightforward with the right tools and techniques, ensuring clean, precise edges without cracking or chipping.
Recommended Tools:
- Fine-tooth circular saw (best for straight cuts)
- Jigsaw with fine-tooth blade (for curves or detailed cuts)
- Utility knife (for scoring very short cuts)
- Clamps and a stable workbench
Step-by-Step Guide:
- Measure and Mark: Use a non-permanent marker and straightedge to outline the cut.
- Secure the Sheet: Clamp it firmly to prevent movement or vibration.
- Select the Right Blade: Use a fine-tooth or carbide-tipped blade to avoid chipping.
- Cut at Moderate Speed: Too fast can melt the sheet; too slow may create rough edges.
- Keep Protective Film On: Prevent scratches by leaving the film during cutting.
- Smooth Edges if Needed: Light sanding gives a professional finish.
Safety Tips:
- Always wear gloves and safety goggles.
- Ensure proper support to avoid cracking during cutting.
How to Install 4mm Polycarbonate Sheets
Proper installation ensures long-term performance, especially for roofing, partitions, and greenhouses.
Installation Steps:
- Prepare the Structure: Ensure the frame is level, clean, and strong enough to support the sheet.
- Allow for Thermal Expansion: Leave small gaps (3–5 mm) around edges for expansion.
- Use Compatible Fasteners: Screws with rubber washers prevent stress cracks and maintain waterproofing.
- Drill Oversized Holes: Holes slightly larger than screws allow for movement due to heat changes.
- Install with UV Side Out: Always place the UV-coated side facing sunlight.
- Avoid Overtightening: Fasten just enough to secure without distorting or cracking.
- Seal Edges if Needed: Use appropriate silicone or tape for outdoor applications to prevent water ingress.
These steps ensure durable, safe, and high-performing installations for a wide range of projects.
Frequently Asked Questions
Is 4mm polycarbonate strong enough for roofing?
Yes, especially in twin-wall form. It handles wind, UV, and light impact well for residential and light commercial roofing.
Can it be curved?
Yes. 4mm sheets can be cold-bent for arched roofing, domes, and decorative shapes.
How long does it last?
Up to 15–20 years when installed correctly with UV protection.
Is it more affordable than thicker sheets?
Yes, 4mm sheets offer excellent value per square meter for light-duty projects.
Bulk Orders & Custom Manufacturing Options
At G-Crystal Plastic Industries, we offer flexible solutions for bulk orders and custom manufacturing, ensuring that businesses, distributors, and importers get exactly what they need.
- Custom Dimensions, Colors, and Coatings: Sheets can be tailored to specific sizes, colors, UV coatings, or surface finishes (frosted, embossed, tinted, twin-wall).
- Fast Lead Times and Worldwide Shipping: We ensure timely production and delivery to over 60 countries, supporting international projects efficiently.
- Dedicated Support for Distributors and Importers: Our team provides guidance on product selection, installation tips, and optimized ordering for large-scale or repeat shipments.
As a global leader in polycarbonate sheet manufacturing, G-Crystal Plastic Industries delivers certified, export-ready products in large volumes. Our commitment to quality, fast lead times, and flexible customization make us the trusted partner for businesses worldwide.
Contact us today to request:
- Product catalogs and technical specs
- Free samples for testing
- Custom production schedules
- Full accessory kits and FOB quotes
