1. Structural Frame Materials

The frame is the backbone of a polyhouse. It must be strong, durable, and resistant to weather conditions such as wind, rain, and heat.

• Galvanized Iron (GI) pipes are the most commonly used material for polyhouse frames. They are coated with zinc, which protects them from rust and corrosion, making them suitable for long-term use. GI pipes offer excellent strength and can easily support the structure for 15–20 years.

• Steel pipes are also used, especially in large commercial polyhouses. They provide high load-bearing capacity but usually require additional anti-corrosion treatment to prevent rusting.

• Aluminum pipes are lightweight and naturally resistant to corrosion. They are easy to install but are more expensive and less commonly used due to lower strength compared to steel or GI pipes.

2. Cladding (Covering) Materials

The covering material plays a crucial role in controlling the internal environment of the polyhouse.

• The most widely used cladding material is UV-stabilized polyethylene (PE) film. This plastic sheet, typically 180–200 microns thick, helps maintain temperature and humidity while protecting crops from harmful ultraviolet radiation. Depending on quality, it usually lasts 3–5 years.

• In some advanced or premium polyhouses, polycarbonate sheets are used. These are rigid, highly durable, and provide better insulation, but their higher cost limits widespread use.

3. Ventilation and Shading Materials

Proper ventilation and shading are essential to prevent overheating and pest infestation inside the polyhouse.

• Shade nets are used to reduce excessive sunlight and heat. They are available in different shading percentages, usually ranging from 30% to 75%, depending on crop requirements.

• Insect nets are installed on sidewalls and vents to block pests while allowing airflow. Common mesh sizes range from 40 to 50 mesh, which are effective against most insects.

4. Foundation and Anchoring Materials

A strong foundation ensures the stability and durability of the polyhouse, especially in areas prone to strong winds.

• Permanent polyhouses generally use concrete foundations, which provide excellent strength and long-term stability. In semi-permanent structures, ground pipes are inserted deep into the soil to support the frame.

• Anchor bolts and base plates are used to firmly fix the structure to the ground and prevent movement.

5. Irrigation and Climate Control Materials

Efficient irrigation and climate control systems are vital for maintaining optimal growing conditions.

• Most polyhouses use drip irrigation systems, which include pipes, emitters, valves, and filters to supply water directly to plant roots. Foggers and misters are often installed to control temperature and humidity, especially during hot weather.

• Additional components such as PVC pipes, water storage tanks, thermometers, and hygrometers help monitor and manage the internal environment effectively.

6. Doors, Fasteners, and Accessories

Though small, these components are essential for the smooth functioning of a polyhouse.

• Polyhouses typically have single or double doors for easy access. Locking channels, springs, clamps, nuts, and bolts are used to secure the covering material and frame. Repair tapes and sealing materials help in maintenance and extending the life of the structure.

Conclusion

Polyhouse construction requires a careful selection of strong structural materials, durable covering films, and efficient irrigation and climate control components. Using high-quality materials not only improves crop productivity but also increases the lifespan of the polyhouse and reduces maintenance costs.

Whether you are planning a small-scale polyhouse or a large commercial setup, investing in the right materials is the foundation of successful protected farming.