Greenhouse Construction: Glazing Materials

Study Notes

Retractable-Roof Greenhouses

Retractable-roof greenhouses can be opened to provide plants with increased light levels and fresh air when weather conditions are favorable.
They can be closed to protect crops from harsh weather.
They allow for preparing outdoor crops for the elements before leaving the greenhouse.
Advantages include reduced disease problems, reduced irrigation due to rainfall, and more effective temperature control.

Shadehouses

Shadehouses are structures used to protect plants from wind, heat, and light intensity.
Synthetic shade cloth is the most widely used covering material, available with varying degrees of shade.

Greenhouse Frameworks

The framework should be strong, yet allow maximum light to reach the plants.
It should require little maintenance.
In northern latitudes, it should be strong enough to withstand heavy snow loads.
Popular framework materials include aluminum, aluminum/steel combinations, wood, galvanized steel, and angle iron.

Greenhouse Glazing

Glazing materials include flexible polyethylene sheets, structured sheets (polycarbonate, acrylic, and fiberglass), and glass.
Polyethylene is the least expensive covering material, but it is not very durable and needs to be replaced every 1-3 years.
Polycarbonate structured sheets are widely used due to their good light transmission, resistance to hail damage, and ease of use.
Acrylic structured sheets have high light transmission, but are more expensive and prone to hail damage.
Fiberglass has poor insulation properties, discolors over time, and loses light transmission as it wears out.
Glass is the best material for crop production, with high light transmission and long lifespan, but it is expensive and may break during hailstorms.

Headhouse

The headhouse is a structure attached to the greenhouse, used for tasks such as storage, potting, office work, and shipping.

Greenhouse Benches

Greenhouse benches are structures that hold plants above the ground.
Materials used for benches include expanded galvanized steel, aluminum, plastic, and rot-resistant wood.
Benches should be narrow enough for workers to reach plants and provide care, with aisle space and growing space in mind.
Common layouts include conventional arrangements, peninsular arrangements, and movable benches.

Description

Discover the different materials used for greenhouse glazing, including their durability, light transmission, cost, and impact on heating costs. Learn about the various considerations for choosing the right glazing material for your greenhouse.