Green-tek ThermaGlas Twinwall Polycarbonate Sheet - 8mm - 71.25in x 17ft - Clear

Green-tek ThermaGlas Twinwall Polycarbonate Sheet - 8mm - 71.25in x 17ft - Clear

Green-tek ThermaGlas Twinwall Polycarbonate Sheet is designed and engineered specifically for commercial greenhouse applications. The 8mm twin-wall cellular structure provides superior insulation and energy efficiency compared to single-layer glazing - retaining heat in winter and minimizing heat buildup in summer. With 99.5% UV protection, a specialized condensate-control underside coating, and shatterproof construction, ThermaGlas delivers long-service-life performance for greenhouse glazing, cold frames, and covered growing structures.

Key Features & Benefits

• 8mm twinwall cellular structure: The dual-wall channel design traps a layer of insulating air that significantly improves thermal performance compared to single-layer polycarbonate or glass.
• 99.5% UV protection: Co-extruded UV-resistant layer on the outer surface blocks virtually all harmful UV radiation, protecting both the polycarbonate sheet and the crops beneath from UV degradation.
• Condensate control underside coating: A specialized coating on the inner surface causes condensation droplets to spread into a thin film that runs off rather than dripping onto plants - maintaining crop quality and reducing disease pressure.
• Shatterproof polycarbonate construction: Virtually unbreakable - 200x stronger than glass - for improved safety and durability in hail, impact, and high-wind conditions.
• Lightweight construction: Significantly lighter than glass, reducing the load on greenhouse frame structures and simplifying installation.
• Clear glazing: Maximizes natural light transmission to support strong plant growth and photosynthesis throughout the growing season.

Who Should Use This

Green-tek ThermaGlas Twinwall is the glazing of choice for commercial greenhouse builders, nursery operators, and serious hobby growers who need reliable, energy-efficient polycarbonate panels for new construction or greenhouse re-glazing. The 8mm thickness provides an excellent balance of insulation, light transmission, and structural performance for a wide range of greenhouse frame designs.

Compatibility

Compatible with standard 8mm polycarbonate glazing systems including Green-tek Polycarbonate U-Profile end caps and H-Profile joining channels. Install with sheets oriented vertically so channels run from ridge to eave for proper condensate drainage. Seal top edges with Green-tek Aluminum Tape and bottom edges with ventilated tape or U-Profile to prevent debris and insect entry into the channels.

Frequently Asked Questions

Which direction should the channels run during installation?

Twinwall polycarbonate sheets should always be installed with the channels running vertically - from the ridge of the greenhouse down to the eave. This orientation allows condensation that forms inside the channels to drain freely out the bottom rather than collecting inside the cells where it can promote algae growth and reduce light transmission.

What accessories are needed to complete the installation?

A complete twinwall installation requires Green-tek Aluminum Tape to seal the top (ridge) edges of the sheets, U-Profile or ventilated closure strips for the bottom edges, and H-Profile joining channels where adjacent sheets meet. Foam closure strips should be used at ridge and eave connections with corrugated or non-flat structural members.

How does 8mm twinwall compare to 4mm single-layer polycarbonate?

The 8mm twinwall cellular structure provides significantly better thermal insulation (lower U-value) than single-layer polycarbonate, reducing heat loss and heating costs. The trade-off is slightly lower light transmission due to the internal wall structure. For most commercial greenhouse applications, the energy savings of 8mm twinwall outweigh the modest reduction in light transmission.

Can ThermaGlas twinwall be cut to custom lengths on site?

Yes. ThermaGlas polycarbonate sheets can be cut to length on site using a fine-tooth circular saw blade or utility knife guided by a straightedge. Always cut with the protective film in place and clean the channels after cutting to remove any debris before installation.