Greenhouse covering
Polycarbonate vs Polyfilm Greenhouse Covering
Covering choice sets your recladding cycle, light transmission and structural load. Polycarbonate lasts far longer per m² but costs more upfront and needs a heavier frame; polyfilm is cheapest to install and replace but is a recurring OPEX line.
Is polycarbonate always cheaper over the life of a greenhouse?
No. It usually wins in cold or hail-exposed climates where heating and damage losses are high. In mild climates with cheap film and cheap labour, double polyfilm on a 3–4 year cycle can be the lower lifetime cost.
| Dimension | Polycarbonate sheet | Double-layer polyfilm |
|---|---|---|
| Typical covering cost | USD 12–30 / m² (6–10 mm twin/triple wall) | USD 1.5–4 / m² per layer, installed |
| Service life | 10–15 years (UV-coated) | 3–4 years (single season in harsh UV) |
| Light transmission (new) | 78–84% (diffused options lower direct light) | 85–91% single layer, 78–83% double |
| Insulation (U-value) | 2.6–3.3 W/m²K (twin wall) | ~6.0 single layer, ~4.0 inflated double |
| Structural load on frame | Higher — heavier purlin/rafter spec | Low — lighter frame acceptable |
| Hail / wind damage | High impact resistance | Vulnerable; repair or reclad |
| Recladding labour | Rare; panel-level replacement | Full-house cycle every 3–4 years |
| Best-fit use | Sidewalls, cold climates, hail belts, long-life assets | Roofs, mild climates, phased or lower-CAPEX projects |
Cost delta at a glance
- •On a 1 ha structure, polycarbonate roofing typically adds USD 90K–250K of CAPEX versus double polyfilm.
- •Polyfilm recladding runs roughly USD 20K–45K per hectare every 3–4 years, plus 1–3 days of production downtime.
- •Over a 12-year horizon the two options often converge; heating savings from polycarbonate insulation decide the outcome in cold climates.
Planning-grade ranges for budgeting only. Actual pricing depends on site, specification, climate and supplier scope.
Choose Polycarbonate sheet when
- Cold or hail-prone climates where heating and damage costs dominate
- Sidewalls and gables on any climate-controlled house
- Assets financed over 10+ years where recladding downtime is unacceptable
Choose Double-layer polyfilm when
- Mild or tropical climates where insulation matters less
- Phase-one projects that need the lowest entry CAPEX
- Crops needing maximum light transmission in low-radiation seasons
Frequently asked questions
No. It usually wins in cold or hail-exposed climates where heating and damage losses are high. In mild climates with cheap film and cheap labour, double polyfilm on a 3–4 year cycle can be the lower lifetime cost.
Only if the frame was specified for the extra dead load and the purlin spacing suits panel widths. Tell your EPC at design stage if a future upgrade is planned, otherwise the frame has to be reinforced.
Ask suppliers for measured transmission at installation and the expected value after five years, plus whether the figure is direct or diffused light. Diffused light often improves canopy uniformity even at a slightly lower total number.