Polycarbonate Sheets
Polycarbonate Panels for Greenhouse Construction
Polycarbonate is the best all-around greenhouse glazing for most growers: it resists impact up to 200x better than glass, insulates far better than single-pane glass, and weighs a fraction as much. Greenhouse Megastore carries clear, opal, and diffused polycarbonate panels in 6mm to 16mm twin-wall and multiwall constructions for hobby greenhouses, commercial structures, carports, and patio covers, all UV-protected and backed by our Low Price Guarantee.
Polycarbonate suits both commercial growers and backyard gardeners because it scales across panel thickness and structure size without changing materials. Commercial builds use thicker multiwall panels for span and snow load; hobby greenhouses use 6mm or 8mm twin-wall for easy handling. Order pre-cut sheets or request custom sizing to match your frame.
Polycarbonate Panel Thickness Comparison
| Thickness | Wall Type | R-Value | Light Transmission | Snow-Load Suitability | Best For |
|---|---|---|---|---|---|
| 6mm | Twin-wall | ~1.62 | ~80% | Light | Hobby greenhouses, patio covers, mild climates |
| 8mm | Twin-wall | ~1.72 | ~80% | Moderate | All-purpose greenhouses, moderate winters |
| 10mm | Twin-/Triple-wall | ~1.89 | ~79% | Heavy | Cold climates needing more insulation |
| 16mm | Multiwall (3–5 wall) | ~2.36 | ~76% | Very Heavy | Harsh winters, high snow loads, commercial builds |
Single-Wall vs. Twin-Wall vs. Multiwall
| Construction | Light Transmission | Insulation | Weight | Best Application |
|---|---|---|---|---|
| Single-wall (corrugated) | up to ~90% | Lowest | Lightest | Sheds, lean-tos, patio covers |
| Twin-wall | ~80% | ~1.72 | Light | Most greenhouses |
| Multiwall (triple/5-wall) | ~76% | Best | Moderate | Harsh climates, commercial |
Polycarbonate vs. Glass vs. Acrylic
| Factor | Polycarbonate | Glass | Acrylic |
|---|---|---|---|
| Impact resistance | Highest (near unbreakable) | Lowest (shatters) | Moderate |
| Insulation | High (multiwall) | Low (single pane) | Moderate |
| Weight | Light | Heavy | Light |
| Light transmission | ~76-82% | ~90%+ | ~92% |
| Relative cost | Low-moderate | High | Moderate |
| Lifespan | 10+ years | Decades | 10+ years |
Why Choose Polycarbonate Sheets
Polycarbonate is up to 250x more impact-resistant than tempered glass and insulates far better, while staying easy to cut, drill, and shape for custom greenhouse roofing, windows, and sidewalls. Twinwall and multiwall panels trap insulating air layers that hold steadier growing temperatures and diffuse light evenly across the canopy.
- Twinwall Polycarbonate Panels: Two air-trapping layers cut heat loss and lower energy costs versus single-wall glazing.
- Multiwall Polycarbonate Sheets:Extra walls raise the R-value further, built for larger structures and colder climates.
- Clear, opal, and diffused options: Clear maximizes light, opal reduces hot spots, diffused spreads coverage evenly — pick by plant and climate need.
All of our polycarbonate panels are UV-protected to prevent yellowing and degradation, ensuring years of clarity and strength. Panels are available in multiple thicknesses, widths, and lengths to fit any greenhouse or outdoor project.
Choosing Polycarbonate Panels by Climate Zone
Your USDA climate zone should guide panel thickness and wall count:
- Zones 7-9 (mild winters): 6mm or 8mm twin-wall: strong light transmission, easy handling.
- Zones 5-6 (cold winters, moderate snow): 8mm or 10mm twin-wall: balances insulation and cost.
- Zones 3-4 (harsh winters, heavy snow): 16mm multiwall: highest R-value and snow-load capacity.
Growers in heavy-snow regions should pair thicker multiwall panels with appropriate framing and purlin spacing. For commercial-scale builds, our team can spec panels and calculate bulk pricing: call 1-888-281-9337.
Trusted Source for Greenhouse Polycarbonate
Polycarbonate panels work across greenhouses, sunrooms, carports, pergolas, and patio covers because the same impact resistance and UV protection apply to any glazed structure. Greenhouse Megastore has supplied these panels to builders, growers, and hobbyists for more than 30 years, with bulk discounts that apply automatically on larger orders.
Shop our complete selection of greenhouse polycarbonate panels today and build a long-lasting, energy-efficient structure that looks great and performs even better.
FAQs About Polycarbonate Sheets
Which polycarbonate thickness is best for harsh winters?
For harsh winters and heavy snow, 16mm multiwall polycarbonate is the best choice. Its R-value near 2.5 retains more heat and its multiwall structure carries greater snow loads than 8mm twin-wall, which suits milder climates.
Is polycarbonate better than glass for cold-climate greenhouses?
Polycarbonate is generally better for cold climates. Twin-wall and multiwall panels trap insulating air that retains heat far better than single-pane glass, while resisting impact and weighing much less, which also lowers framing cost.
How much light transmission do twin-wall panels lose vs. single-layer?
Single-wall corrugated polycarbonate transmits up to about 90% of light; twin-wall transmits around 80%. You trade a modest amount of light for substantially better insulation, which benefits most plants in cooler conditions.
What thickness handles snow loads in zone 5?
In zone 5, 8mm or 10mm twin-wall handles typical snow loads for most hobby and mid-size greenhouses, while 16mm multiwall is the stronger choice for heavy-snow sites or commercial structures. Match panel thickness to your framing and local snow-load rating.
