When building a commercial greenhouse, picking the right covering material isn’t just about upfront costs. It directly affects your crop yield, energy efficiency, and long-term maintenance. That’s why many growers are starting to move away from traditional glass to lighter and tougher polycarbonate sheets. But here’s the tricky part: there are tons of polycarbonate sheet options out there, and not all are created equal. So, which one actually works best for a commercial greenhouse?
No worries. In this article, INSONGREEN will walk you through everything you need to know about polycarbonate sheets, their key features, popular types, and how to choose the best one. Whether you’re designing a large multi-span greenhouse or just looking to upgrade your current setup, you’ll find solid, practical advice right here.
Best Greenhouse Polycarbonate Sheets – Key Features
The polycarbonate sheets you choose will influence everything—from the amount of sunlight that enters to how well your greenhouse retains heat, withstands adverse weather, and the maintenance costs involved. So, what exactly makes a sheet “good” for greenhouse use? To assist you in making a decision, we’ve broken it down into six key factors. Once you understand what to look for, it’s much easier to compare products and select the one that best fits your needs.
1. Weather Resistance
Polycarbonate is a strong plastic, but long-term sun exposure can still cause it to yellow and break down. That’s why good greenhouse sheets come with UV-resistant coatings or co-extruded UV layers. These prevent sun damage and help your panels last longer. So always check if the sheet has proper UV protection.
2. Light Transmission
The ideal light transmission rate for greenhouse use is usually between 80% and 90%. Good polycarbonate sheets—especially those made with virgin material—can hit that range. Just keep in mind that if there’s no UV protection, the clarity will drop over time.
3. Insulation
If staying warm and cutting energy costs matter to you, insulation is key. Multi-wall polycarbonate sheets have built-in air pockets that help hold in heat—especially during cold months. If your greenhouse faces harsh winters or pricey heating bills, go with thicker, multi-layer panels made specifically for greenhouse use.
4. Strength and Impact Resistance
Polycarbonate is much tougher than materials like glass or polyfilm. When you choose high-quality sheets from trusted manufacturers, they can easily withstand hail, heavy wind, and snow without cracking. That’s a big deal if your area often gets hit with storms.
5. Lightweight Design
One big plus of polycarbonate is that it’s lightweight. That makes the panels easier to transport, lift, and install—which can save you both time and labor costs.
6. Anti-Drip Coating
Condensation happens all the time in greenhouses. But when water drips straight onto your plants, it can lead to disease or damage. That’s why high-quality polycarbonate sheets come with an inner anti-drip layer. It turns condensation into a thin film that slides off to the sides, instead of dripping down onto your crops.
Types of Polycarbonate Sheets for Greenhouses
Greenhouse polycarbonate sheets usually come in three main types. Each type has a different structure, which affects how much light it lets through, how well it insulates, and where it’s best used. Knowing these differences is key to choosing the right material.
1. Solid Sheets
Also known as clear or monolithic sheets, these are made from a single, solid layer. Thickness typically ranges from 1.8mm to 20mm. The main advantage is clarity—light transmission is excellent, almost like glass, but the sheet is stronger, lighter, and easier to handle.
The downside? It’s not very effective at retaining heat since it consists of only one layer. That’s why solid sheets are commonly used in small greenhouses or locations where maximizing light is essential. If you’re in a warm area and don’t have to worry about cold winters, this type is an excellent choice.
2. Multi-Wall Sheets
Also called twin-wall or structured sheets, these have hollow chambers between layers. Common designs include twin-wall, triple-wall, four-wall, X-shape, and honeycomb structures. They’re great for insulation and much lighter than solid sheets. While the light transmission is a bit lower, it’s still enough for plant growth. These sheets are widely used in large-scale commercial greenhouses where energy efficiency really matters.
3. Corrugated Sheets
These sheets are shaped like roofing tiles and are basically solid sheets molded into waves. Thanks to their shape, they’re tough and drain water well. However, insulation isn’t their strong suit. Because of that, corrugated sheets are mostly used for greenhouse roofing or rain covers—not as the main covering for commercial greenhouses.
How to Choose the Right Polycarbonate Sheets
Now that you’re familiar with the main types of polycarbonate sheets, the next step is choosing the right one based on your actual greenhouse project. You’ll want to consider your budget, local climate, and the crops you plan to grow.
1. Based on Climate
For areas with mild weather and a need for high-light transmission, twin-wall sheets with thicknesses between 6mm and 12mm are a great choice. These let in up to 80% of natural light—perfect for most crops. But if your greenhouse is located in a region with strong winds, heavy hail, or cold winters, you’ll need something stronger. Go with four-wall or honeycomb-style sheets. These provide better insulation, though they let in slightly less light.
2. Based on Budget
Polycarbonate sheets sit in the middle range when it comes to cost. They’re more expensive than plastic film but cheaper than glass. The upside? They last much longer and require less maintenance. So, if your budget allows, polycarbonate is a smart investment in the long run.
3. Based on Crop Needs
Different crops have different requirements. Make sure the sheet you choose offers the right balance of light transmission and insulation to keep your plants happy and healthy.
4. Brand & Certifications
Stick with reputable brands and experienced manufacturers. Look for sheets that meet international quality standards. It’s not just about durability—these choices also impact your maintenance needs and even crop performance down the road.
5. Don’t Forget the Details
Beyond the basics, choosing the best sheet depends on your unique situation. We’ve covered this in more detail in our article How to Choose Polycarbonate Panels for Greenhouses. If you want a deeper dive, be sure to check it out.
Conclusion
Choosing the right polycarbonate sheet for your greenhouse is more than just a material pick—it’s a smart, long-term investment. Every detail matters: weather resistance, light diffusion, insulation, sheet structure, and how well it fits your setup. At INSONGREEN, we’re dedicated to helping growers worldwide find better-performing, cost-effective polycarbonate greenhouse solutions. If you’re looking for tailored advice, samples, or sourcing support, feel free to reach out—we’re happy to help.
