Polycarbonate Sheet Span & Load Chart: How Far Can PC Panels Span? (2026)
4 mm twin-wall polycarbonate spans up to 700 mm between supports; 16 mm triple-wall spans 1,200–1,400 mm; 25 mm 5-wall reaches 1,800 mm. Use this span chart with the matching snow and wind load ratings before specifying any roofing or glazing project.
Multiwall polycarbonate: maximum span between supports
| Sheet thickness & structure | Maximum span between supports | Typical use |
|---|---|---|
| 4 mm twin-wall | 600–700 mm | Hobby greenhouse, mild climate |
| 6 mm twin-wall | 800–900 mm | Year-round growing, occasional snow |
| 10 mm twin-wall | 1,000–1,100 mm | Carport and patio roofs, commercial greenhouse |
| 16 mm triple-wall | 1,200–1,400 mm | Skylights, industrial roofing, snow >1.5 kPa |
| 25 mm 5-wall | 1,500–1,800 mm | Pool enclosures, long-span architectural roofs |
Solid polycarbonate: maximum span between supports
| Sheet thickness | Maximum span between supports | Typical use |
|---|---|---|
| 4 mm solid | up to 400 mm | Horizontal glazing — keep supports close |
| 12 mm solid | up to 900 mm | Security glazing, noise barriers |
Solid sheets deflect more than multiwall at the same span: for walkable or security glazing always use the conservative end of the range and confirm the design with our engineers.
Snow and wind load ratings (multiwall)
| Sheet | Support spacing | Snow load | Wind load |
|---|---|---|---|
| 10 mm multiwall | 1,000 mm | ~0.75 kPa | ~1.0 kPa |
| 16 mm multiwall | 1,000 mm | ~1.5 kPa | ~2.0 kPa |
kPa = kilonewtons per m²: 1 kPa ≈ 100 kg/m² of snow. Loads above these values require tighter support spacing or a thicker structure — send us your regional snow/wind zone and we will confirm suitability.
Recommended thickness by application (span-aware)
| Application | Recommended type | Recommended thickness |
|---|---|---|
| Hobby greenhouse | Multiwall (twin-wall) | 4–6 mm |
| Commercial greenhouse | Multiwall (twin/triple) | 8–16 mm |
| Carport / patio cover | Corrugated or twin-wall | 0.8 mm corr. / 6 mm twin |
| Skylight / rooflight | Multiwall or solid | 10–16 mm multiwall |
| Industrial roofing | Multiwall (triple/5-wall) | 16–32 mm |
| Noise barrier | Solid | 8–15 mm |
| Machine guard | Solid | 4–10 mm |
| Security glazing | Solid | 10–20 mm |
| Architectural facade | Multiwall or solid | 10–25 mm multiwall |
| Pool enclosure | Multiwall (triple-wall) | 16–25 mm |
| Indoor partition / display | Solid | 2–4 mm |
FAQ: Polycarbonate span and load
How far can 10 mm polycarbonate span between supports?
10 mm twin-wall polycarbonate spans 1,000–1,100 mm between supports for roof applications. At 1,000 mm support spacing it handles approximately 0.75 kPa snow load and 1.0 kPa wind load.
What thickness polycarbonate do I need for a greenhouse?
For hobby greenhouses 4–6 mm twin-wall is standard (spans up to 900 mm). Commercial greenhouses use 8–16 mm twin or triple-wall sheets spanning 1,000–1,400 mm, depending on the regional snow load.
Can polycarbonate carry a person or heavy snow?
Solid sheets are load-bearing: 12 mm solid spans up to 900 mm for security glazing. For walkable installations confirm the design with our engineers. Standard multiwall handles typical roof loads when spans stay within the chart above.
What does kPa mean for polycarbonate load ratings?
kPa (kilopascal) is load per square metre: 1 kPa ≈ 100 kg/m². A 16 mm multiwall sheet rated at 1.5 kPa snow load supports about 150 kg/m² at 1,000 mm spacing.
Do I need support battens at the end of the sheet?
Yes — always support the sheet ends (e.g. 40–50 mm bearing) and use aluminium profiles with EPDM gaskets. Unsupported ends are the most common cause of sheet failure under load.
What span is safe for a carport roof in 0.5 kPa snow zone?
6 mm twin-wall spans up to 800–900 mm and is suitable for carports in mild zones. For 0.5 kPa snow, use 10 mm twin-wall at 1,000 mm spacing — it keeps deflection well within limits.
Related: sheet weight calculator · U-value & insulation
Confirm the right thickness and span for your project. Send your roof dimensions, support spacing and regional snow/wind zone — our engineers will confirm the correct structure and quote within 24 hours.