Greenhouse Heat Load Calculator
Estimate the heat load of a greenhouse from glazing area, U-value and indoor–outdoor temperature difference.
How to Use the Greenhouse Heat Load Calculator
- Sum up roof + walls area in m².
- Enter the glazing U-value.
- Enter the target indoor–outdoor temperature difference.
- Click Calculate.
使用例
- •Sizing greenhouse heaters.
- •Winter energy budgeting for horticulture.
- •Teaching building-envelope physics.
計算式
Q = U × A × ΔT. Typical U for single-pane glass or film ≈ 6 W/m²·K; double glazing or twin-wall polycarbonate drops to 2.5–4 W/m²·K.
よくある質問
What U-value should I use?
Film/single glass ≈ 6, double-pane ≈ 3, twin-wall polycarbonate ≈ 3.5, triple-wall ≈ 2.5 W/m²·K. Add roof and sidewalls to get the total area A.
Is infiltration included?
No. Leaky greenhouses can double the heat load. Multiply the result by 1.5–2 for old structures.
Does solar gain matter?
For daytime estimates yes — subtract an average of 30–60 W/m² of ground area on sunny days. This calculator gives the night-time / worst-case load.