Polycarbonate for Vehicle Weight and Heavy Point Loads: Thickness Tables for Access Panels
Can Polycarbonate Support Vehicle and Equipment Weight?
Yes — when the panel is thick enough and the support spacing is controlled. Polycarbonate is the only transparent sheet that can carry vehicle wheel loads in access covers, inspection pits and plant-room walkways. The rule that governs these applications is simple: point loads, not distributed loads, set the required thickness. A 10–12 mm solid panel that easily carries 150 kg of people may fail under a single forklift wheel carrying 1,500 kg concentrated on a small contact patch.
Point Load vs Distributed Load: Why It Matters
- Distributed load (people, snow, storage): load spreads across the panel — thickness driven by span and deflection limit
- Point load (vehicle wheel, machine foot, ladder base): force concentrates on a small area — requires far greater thickness, or local reinforcement
A standard forklift wheel contact patch is roughly 150 mm × 60 mm. A 3.5 t axle puts ~1.75 t on that patch — roughly 10× the load of a walking person on a similar area.
Thickness Table for Vehicle / Heavy Point Loads
| Load case | Max wheel/foot load | Solid PC thickness | Max span |
|---|---|---|---|
| Pedestrian maintenance (1 person) | 1.5 kN | 16 mm | 900 mm |
| Pallet jack / hand truck | 10–15 kN | 20–25 mm | 600–700 mm |
| Forklift (2–3 t capacity, loaded) | 20–35 kN per wheel | 25 mm + steel frame | 400–500 mm |
| Stationary equipment foot | Per machine spec | 25 mm + load-spreading plate | Design check |
Critical rule: for wheel loads above ~15 kN, polycarbonate must sit in a steel or aluminium sub-frame that carries the load around the panel. The sheet then works as a transparent insert, not the primary structural member.
Standards for Heavy-Load Polycarbonate
- EN 1991-1-1 — imposed loads (vehicle categories per EN 1991-1-1 Table 6.4)
- ASCE 7-22 — live loads and concentrated load provisions
- ISO 178 / ASTM D790 — flexural modulus for deflection calculation
- ISO 527 / ASTM D638 — tensile properties for yield-limit checks
- ASTM D256 — Izod impact (polycarbonate ≈ 850 J/m, ~27× glass and ~28× acrylic)
Design Checklist for Vehicle-Weight Access Panels
- Identify the worst point load — not the average; the heaviest single wheel or foot
- Size the sub-frame first — steel perimeter frame carries the vehicle; panel is the infill
- Keep the panel span ≤ 500 mm for forklift traffic
- Use 25 mm solid or thicker — 20 mm is marginal for repeated wheel passes
- Specify edge bearing — panels need full-width bearing on the frame, not point fixing
- Add a load-spreading plate under stationary machine feet
- Confirm with a deflection check — send load, span, thickness and support detail to the factory
FAQ: Polycarbonate Under Heavy Loads
What is the wind load rating of polycarbonate sheet?
Wind load is a distributed pressure (e.g. 0.5–2.0 kPa depending on region). A 10 mm multiwall panel with supports at 1.0–1.2 m typically resists the standard wind loads; the limit is deflection and fixing, not material strength. Use the wind zone map for your project and check the supplier’s span table.
Can a forklift drive over polycarbonate?
Only over 25 mm solid polycarbonate in a steel frame with spans under ~500 mm, and even then only for occasional crossing. Continuous forklift traffic should use steel covers with polycarbonate windows.
How much weight can a 12 mm solid polycarbonate sheet hold?
As a distributed load on a 600 mm span, roughly 2–4 kPa (200–400 kg/m²). As a point load, far less — a concentrated 10–15 kN load is already near the limit. Point load cases need 20–25 mm.
Does polycarbonate creep under constant heavy load?
Yes — polycarbonate creeps under sustained load at elevated temperature. For permanently loaded panels (equipment standing on the sheet), apply a safety factor of 2–3 to the short-term table values and confirm with the supplier.
Get a Verified Load Answer
Send your access-panel drawing with the heaviest wheel or foot load, span, support detail and thickness to Bakway. We respond with a verified thickness recommendation and mill certificate on request — no guesswork on load-bearing transparent panels.