Inner Thermal Screens in Venlo Greenhouses: Why Installation Details Matter

In cold weather, heat can escape through greenhouse glazing and structure. An inner thermal screen can reduce heat transfer and help limit heating demand when it is correctly selected, installed and operated. Its performance depends on the screen material, coverage, air leakage, greenhouse geometry, climate and operating schedule.

Why layout and sealing matter

A screen creates a separation between the crop zone and the roof or side glazing. Gaps, poorly sealed joints or unsuitable clearances can allow air movement that reduces the intended insulating effect. Retraction systems, drainage, condensation management and access for maintenance also need to be considered at the design stage.

Avoid universal spacing rules

There is no single side clearance or mounting height that fits every Venlo greenhouse. The appropriate layout depends on span and gutter geometry, crop height, equipment, ventilation paths, screen material and local winter conditions. Computational fluid dynamics (CFD) can help compare design options, but results depend on model assumptions and should be checked against suitable measurements when possible.

Project design checklist

• Define the target use: energy saving, crop protection, light control or a combination.
• Coordinate the screen with vents, circulation fans, heating pipes, gutters, crop rows and service access.
• Specify how edges and joints will be sealed and how condensation will be managed.
• Check the screen’s light transmission, thermal properties, durability, fire requirements and operating mechanism with the supplier.
• Estimate energy savings using local weather and operating data; do not assume a screen can replace heating in cold conditions.

An inner screen is one part of the greenhouse climate system. Project-specific design and commissioning are more reliable than applying a spacing recommendation from a different site.