Choosing the right cover for your polytunnel is just as important as choosing the frame. The structure provides strength, but the cover determines light levels, water penetration, airflow and crop protection.
At Greenhouse & Polytunnels, we offer three primary cover options: greenhouse plastic film, netting, and shade cloth. Each serves a different purpose depending on what you are growing and the level of protection you need.
1. Greenhouse Plastic Film – Maximum Protection & Climate Control
Our greenhouse option uses a professional-grade 250 micron plastic film, the highest quality greenhouse film available in Australia. We are the exclusive national supplier of this heavy-duty 250µm cover.
Why growers choose 250µm greenhouse film:
- 88–92% PAR light transmission with high diffusion
- Anti-drip and anti-condensation internal coating
- Thermal retention reduces heat loss by 20–30%
- UV stabilised for 10+ year lifespan
- Chemically resistant for commercial growing
- Rated for winds up to 150km/h and light hail
Unlike netting or shade cloth, plastic film does not allow rainwater through. This gives you full control over irrigation and protects crops from heavy rainfall, frost and harsh weather.
For ventilation, our Elite kits and above include a full door and roll-up side walls with insect mesh behind them. This allows airflow without compromising crop protection.
Best suited for: commercial vegetable production, climate-sensitive crops, harsh weather zones and long-term installations.
2. Net House – Protection with Airflow
Our net houses use black knotless polyethylene netting (5mm x 5mm mesh, 55gsm, UV treated and Victorian compliant) as standard.
Customers can upgrade to a premium 9-ply high-density polyethylene netting (19mm x 19mm mesh, 1.25mm twine thickness, 84gsm) for heavier-duty applications.
Netting allows:
- Rainwater to pass through naturally
- Full airflow
- Temperature moderation without full enclosure
If selecting the larger 19mm mesh upgrade, beneficial insects such as bees may be able to enter, which can assist with pollination in certain growing setups.
Best suited for: orchards, crop protection from birds, hail mitigation and growers wanting airflow without full weather sealing.
3. Shade House – Light Reduction & Heat Control
Our shade houses use 180gsm High-Density Polyethylene (HDPE) shade cloth, typically 50% UV block in white.
Shade cloth allows rainwater and airflow to pass through while reducing heat and direct sun exposure.
This makes it ideal for:
- Hardening off seedlings
- Summer vegetable production
- Nurseries
- Reducing heat stress in extreme climates
Unlike greenhouse plastic, shade cloth does not create a sealed growing environment. Instead, it moderates temperature while maintaining natural rainfall and airflow.
Water, Animals & Perimeter Security
It is important to understand that no structure is completely animal proof. A determined animal will almost always find a way in.
During professional installation, we typically bury the cover along the sides to improve perimeter security. Some customers go further by:
- Installing sleepers around the base
- Adding wire mesh around lower walls
- Creating reinforced entry points
There are many creative ways to strengthen the perimeter depending on your site and the type of wildlife in your area.
Which Cover Is Right for You?
If you want full climate control and maximum protection, the greenhouse polytunnels are the strongest option.
If you want airflow and rain penetration with crop protection, a net house may be ideal.
If your goal is heat reduction and light management, a shade house provides a practical solution.
Call or email us at sales@greenhousepolytunnels.com.au or 0418 438 774 and we’ll help you choose the right cover for your growing setup.
