Shanghai Gokai Industry Co,.Ltd.
Call Us: +86-18918606548
Call Us: +86-18918606548
- Product Name
- Product Keyword
- Product Model
- Product Summary
- Product Description
- Multi Field Search
Views: 269 Author: Gokai Publish Time: 2026-10-22 Origin: Site
Content Menu
● What Are Polycarbonate Hollow Roofing Sheets?
● Main Advantages of Polycarbonate Roofing Panels
>> Lightweight Handling and Lower Roof Dead Load
>> Impact Resistance for Exposed Applications
>> Daylight Without a Fully Open Roof
>> Insulation From a Cellular Structure
>> Flexibility in Appearance and Roof Design
● How to Choose Polycarbonate Hollow Sheet for Roofing
>> Begin With the Application and Climate
>> Match Thickness to Load and Support Conditions
>> Specify UV Protection Clearly
● Installation Details That Protect Long-Term Performance
>> Allow for Thermal Expansion
>> Orient Channels for Drainage
>> Use Appropriate End Closures
>> Check Chemical Compatibility
● Limitations Buyers Should Consider
● A Practical OEM Purchasing Workflow With Gokai
>> 1. Prepare a Complete Inquiry
>> 2. Compare Equivalent Specifications
>> 3. Approve Samples and Acceptance Criteria
>> 4. Confirm Export Packing and Receiving Checks
● Request a Project-Specific Roofing Proposal
>> Are Polycarbonate Hollow Sheets Suitable for Greenhouse Roofing?
>> What Thickness of Polycarbonate Roofing Panel Should I Choose?
>> Will Polycarbonate Roofing Turn Yellow?
>> Can Polycarbonate Roofing Panels Withstand Hail?
>> Can I Walk on Multiwall Polycarbonate Roofing?
>> Can Gokai Provide OEM Polycarbonate Hollow Sheet?
Polycarbonate roofing panels combine daylight transmission, impact resistance, and lightweight construction. For greenhouse operators, building contractors, and distributors, polycarbonate hollow sheet offers another important advantage: its cellular structure improves thermal insulation without the weight of solid glazing.
However, a successful roof depends on more than the material name. Sheet structure, UV protection, support spacing, drainage, and installation details all influence performance.
My starting point when comparing specifications is simple: evaluate the complete roofing system, not just the sheet price. This guide explains the advantages, limitations, and purchasing checks that help buyers select suitable panels and prepare an effective OEM inquiry for Gokai.
Polycarbonate hollow sheet contains parallel internal channels separated by thin ribs. Common configurations include twinwall, triplewall, and more complex multiwall structures.
These cavities reduce material weight and improve resistance to heat transfer. The ribs also contribute stiffness, although actual load capacity depends on the complete sheet design and installation.
Three product categories should not be confused:
- Hollow or multiwall sheet prioritizes lightweight glazing and thermal insulation.
- Solid polycarbonate sheet provides uninterrupted transparency without internal channels.
- Corrugated polycarbonate uses a profiled shape and requires its own fixing and overlap details.
Installation instructions are not interchangeable. Select the sheet and its compatible connection system together.
Multiwall panels can substantially reduce glazing weight. As an illustrative manufacturer example, a published 10 mm twinwall product weighs approximately 1.7 kg/m².
Lower weight can simplify handling, reduce lifting requirements, and ease replacement work. It may also reduce the permanent load imposed on the supporting structure.
However, lightweight sheets do not automatically justify a lighter frame. Wind uplift, snow, connections, and local building requirements still govern structural design.
For international buyers, compare packing dimensions and container utilization as well as sheet weight. Bulky panels can occupy considerable shipping space.
Polycarbonate offers strong impact resistance, making it useful for canopies, covered walkways, greenhouses, and rooflights.
Compared with brittle glazing, it can reduce the risk of dangerous shattered fragments. Nevertheless, "impact resistant" does not mean immune to damage.
Hail performance depends on sheet thickness, structure, temperature, weathering, and test conditions. Request product-specific evidence instead of relying on a universal strength multiplier against glass.
Roof panels are also not walking surfaces. Installation and maintenance require suitable access equipment supported by the building structure.
Transparent and translucent panels introduce natural light while providing weather protection.
Clear sheets generally prioritize light transmission. Opal, tinted, and solar-control grades offer different combinations of brightness, diffusion, and solar transmission.
The brightest option is not always the most comfortable. A clear canopy may admit unwanted summer heat, while a dark panel may reduce useful daylight excessively.
Evaluate visible light transmission and solar heat gain separately. UV protection alone does not establish how cool the space below will feel.
The air spaces inside hollow panels improve thermal insulation compared with single-layer glazing.
The relevant measure is U-value, expressed in W/m²·K. A lower value indicates less heat transfer under the stated calculation or test conditions.
Importantly, thickness alone does not determine insulation.
For example, one published product range lists these values:
| Sheet construction | Thickness | Published U-value |
|---|---|---|
| Twinwall | 10 mm | 2.9 W/m²·K |
| Seven-wall | 10 mm | 2.3 W/m²·K |
These figures illustrate how internal structure affects performance. They are third-party product examples, not Gokai specifications.
Whole-roof performance also depends on framing, joints, air leakage, and installation quality.
Polycarbonate roofing sheets are available in different structures, colors, and light-transmission levels.
Some products can be cold-curved within a manufacturer-defined minimum radius. This can support arched greenhouses and curved canopies without heat forming.
However, bending limits vary with sheet construction. Confirm the permitted radius and bending direction for the exact product rather than applying a generic rule.
Define what the roof must achieve before selecting a thickness.
| Application | Main priority | Specification questions |
|---|---|---|
| Commercial greenhouse | Crop light and moisture management | What light diffusion, condensation control, and ventilation are needed? |
| Patio or walkway canopy | Comfort and weather protection | What daylight level and solar control are appropriate? |
| Industrial rooflight | Daylighting and compliance | What fire documentation, load resistance, and connections are required? |
| Enclosed sunroom | Thermal comfort | What U-value, solar heat gain, shading, and ventilation are necessary? |
A roof in a snowy climate needs a different assessment from an open canopy in a hot coastal location.
Provide the project location and intended use when requesting recommendations.
There is no universally correct thickness for a greenhouse, patio, or commercial roof.
Selection depends on:
- Local wind pressure and uplift.
- Snow load and possible accumulation.
- Panel dimensions and support spacing.
- Sheet structure and area weight.
- Edge restraint and connection details.
- Permitted deflection.
Request load-span information for the proposed product. A thickness recommendation without its support conditions is incomplete.
Outdoor sheets require appropriate protection against sunlight-driven degradation.
Some products have UV protection on one side; others have it on both sides. For single-sided products, the protected face must point toward the sun.
Confirm the protected surface, identification method, weathering documentation, and written warranty conditions.
Avoid interpreting a warranty period as an unconditional service-life guarantee. Coverage may depend on installation, maintenance, geography, and defined performance thresholds.
Polycarbonate changes dimensions with temperature. Restrained movement can contribute to distortion, stress, and connection problems.
For illustration, using a published expansion coefficient of 0.065 mm per meter per degree Celsius, a 3-meter panel experiencing a 50°C temperature change would change length by approximately 9.75 mm.
This is an explanatory calculation, not a universal installation gap. Actual allowances must follow the sheet and profile supplier's requirements.
Connections must accommodate movement while maintaining adequate edge engagement. Where through-fixing is permitted, follow the specified hole sizes, washers, and tightening instructions.
On a pitched roof, internal channels should follow the roof slope so condensation can drain toward the lower edge.
Set the roof pitch according to the selected system's instructions. Different products specify different minimum slopes; a single number should not be applied to every roof.
Address wall junctions, ridges, gutters, and end closures in the design. Sheets cannot compensate for inadequate flashing.
Open channels need protection against dirt, insects, and moisture contamination.
A typical pitched multiwall arrangement uses impermeable tape at the upper end and ventilating filter tape at the lower end, protected by suitable end profiles.
Follow the product instructions because curved roofs and other configurations may require different details.
Keep drainage openings clear. Filling every opening with sealant can trap moisture rather than solve the underlying problem.
Use only compatible sealants, gaskets, cleaners, and adjacent materials.
For routine cleaning, follow the supplier's approved method and avoid abrasive tools, dry rubbing, and unapproved solvents.
Never assume a sealant is suitable simply because it is sold for roofing. Chemical incompatibility can damage polycarbonate even when the joint initially looks satisfactory.
Polycarbonate hollow roofing sheet offers practical benefits, but it is not the best answer to every requirement.
Potential limitations include:
- Lower surface scratch resistance than glass.
- Visible ribs that interrupt clear views.
- Solar heat buildup under unsuitable glazing.
- Channel contamination if closures fail.
- Dependence on compatible profiles and installation workmanship.
Fire performance also requires careful verification. Polycarbonate is a thermoplastic, not a noncombustible material. Obtain documentation relevant to the exact grade, thickness, structure, and intended application.
Likewise, no credible cost comparison should declare polycarbonate universally cheaper than metal roofing. The materials serve different functions, particularly when daylight is required.
Gokai supplies polycarbonate hollow sheet and other sheet materials and offers OEM services to global customers.
For procurement, my recommendation is to make verification the central step between quotation and bulk ordering.
Provide:
- Destination country and project application.
- Required dimensions, quantity, and preferred structure.
- Color and daylight requirements.
- Intended support spacing and design loads.
- UV-protection and documentation requirements.
- Packaging, labeling, and delivery expectations.
Ask Gokai to confirm available customization, minimum quantities, production tolerances, and lead times in writing.
Two panels with the same nominal thickness may have different wall structures, area weights, and performance.
Compare quotations against the same technical requirements. Include connection profiles, tapes, flashings, freight, cutting waste, and installation labor in the purchasing assessment.
The lowest sheet price is not necessarily the lowest installed cost.
Review samples before committing to volume.
Check dimensions, thickness, area weight, color consistency, channel condition, protective film, and identification of the UV-protected face.
Visual inspection cannot verify UV-layer performance or fire classification. Those requirements need appropriate documentation or agreed testing.
Record the approved sample and acceptance criteria so both parties understand what the shipment must meet.
Agree how sheets will be supported and protected during transport.
On arrival, inspect for crushed edges, scratches, contamination, moisture, and quantity discrepancies. Record damage before distribution or installation.
For repeat OEM orders, retain batch identification and inspection records to support traceability.
Send Gokai your project location, roof dimensions, application, estimated quantity, and preferred sheet structure.
Request confirmation of suitable supply options, available OEM customization, supporting technical documents, and export packing arrangements. A clear specification helps turn a general inquiry into a comparable, project-ready quotation.
Yes, when the selected product meets the greenhouse's light, load, insulation, and moisture-management requirements. Consider crop needs, ventilation, and whether a condensation-control surface would be useful.
Thickness must be selected alongside sheet structure, panel size, support spacing, wind, and snow loads. Use product-specific load-span information and obtain structural review where required.
Unprotected polycarbonate can degrade under sunlight. Suitable UV protection helps limit weathering, but performance varies by product and exposure. Check written coverage for yellowing, light-transmission loss, and other defined changes.
Suitable grades can provide strong hail resistance, but no general claim covers every hailstorm. Ask for test conditions, supported panel configurations, and applicable warranty exclusions.
No. Do not step directly on the panels. Use approved access equipment and fall-protection procedures, with working loads transferred safely to structural supports.
Gokai offers OEM services to global customers. Confirm the requested dimensions, colors, structures, labeling, packaging, quantities, and performance requirements directly before approving an order.
1. [Acme Plastics — "The Advantages of Polycarbonate Roofing Panels"]
Original article used to identify the main topic and content gaps. Its broad claims concerning comparative strength, roof costs, weather resistance, and service history were not adopted as universal product guarantees. [acmeplastics]
2. [Palram Industries — "SUNLITE® Multiwall Polycarbonate Sheet," Australia]
Supports the explanation of cellular construction, applications, product-specific area weight, UV-protection options, cleaning precautions, and selection factors. Its dimensions table lists 10 mm twinwall at 1.7 kg/m² with a U-value of 2.9 W/m²·K, and 10 mm seven-wall at 1.9 kg/m² with a U-value of 2.3 W/m²·K. The published thermal-expansion coefficient supplies the basis for the illustrative movement calculation. These values describe the referenced products, not Gokai products. [palram]
3. [SABIC — "LEXAN™ THERMOCLEAR™ Multiwall Polycarbonate Sheet: Technical Manual," March 2013]
Supports the distinction between sheet structures, U-value interpretation, solar transmission, impact-test limitations, UV weathering, and product-specific fire performance. This historical technical manual provides engineering background; buyers should request current documents for the actual product and destination market. [sabic]
4. [Palram Industries — "SUNLITE® Plus: Installation Instructions for Greenhouses"]
Supports recommendations on channel orientation, support conditions, slope, UV-side identification, protective-film removal, upper and lower end closures, drainage, compatible sealants, and safe access. Its fixing dimensions and bending limits are product-specific and should not be transferred automatically to other sheets. [palram]
5. [Palram Industries — "Thermal Expansion and Polycarbonate Roofing Sheets"]
Supports the discussion of thermal movement, installation clearances, fixing-hole allowances, and connections that accommodate expansion and contraction. [palram]
6. Gokai — Company information supplied in the project brief.
The statements that Gokai supplies polycarbonate hollow sheet and offers OEM services worldwide come from the supplied brief. No public company-page URL, customer reviews, product certificates, test reports, or warranty documents were provided for verification. Accordingly, no unsupported customer testimonials, completed projects, certifications, or guaranteed product values have been added.
