KEDER GREENHOUSE
PERFORMANCE
Keder Energy Saving Comparisons
We are really proud of the high quality and energy saving properties of the Keder cladding system and we are delighted to share the comparisons of our 9 layer laminate against other materials used in typical greenhouse or polytunnel construction.
R-Value Thermal Resistance
Thermal resistance is the temperature difference (at a steady state) between two defined surfaces.
The higher the number, the better it is
Keder 1.7
Single Glazed Glass Greenhouse 0.7
Single Glazed
PE Film 0.7
Single Glazed
Polycarbonate 0.7
Double Glazed
Polyethylene with
2" air gap 0.7
U- Value Thermal Conductance
Thermal conductance is the rate of time (at a steady state) the heat flows through a measured unit of material, induced by a temperature difference.
The lower the number, the better it is
Keder 0.5
Single Glazed Glass Greenhouse 1.4
Single Glazed
PE Film 1.4
Single Glazed
Polycarbonate 0.9
Double Glazed
Polyethylene with
2" air gap 0.7
K- Value Thermal Conductivity
Thermal conductivity is the rate of time (at a steady state) the heat flows through a homogeneous material, induced by a temperature gradient.
The higher the number, the better it is
Keder 27.0
Single Glazed Glass Greenhouse 2.3
Single Glazed
PE Film 3.1
Single Glazed
Polycarbonate 8.7
Double Glazed
Polyethylene with
2" air gap 4.9
Although we are comparing very different products, at first glance consumers often confuse a Keder Greenhouse with a Polytunnel and often expect our prices to be in line with Polytunnel prices.
Buyers of polytunnels often say to us "If they had their time over again, they would invest in a Keder, as the long life, easy maintenance, diffused light and extremely superior materials is well worth the initial investment".
As you can see from the figures above, there really is no comparison.
Snow Load Testing
Keder cladding is engineered for strength and durability, capable of withstanding extreme weather conditions including high winds and heavy snowfall. A real-world snow load test was conducted in Amherst, New Hampshire, USA, in February 2012 to demonstrate its performance.
Test Conditions:
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A 2m x 2m sheet of LP-Keder was tested.
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Two sides were secured using the LP-Keder-Lock Profile (PVC).
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The remaining sides used a tongue-and-groove system with Cambia battens.
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Snow weight was measured (5 US gallons = 20.5 lbs).
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A pyramid shape was used to simulate snow accumulation for load estimation.
Results:
Using standard U.S. CE (Certified Engineer) calculations:
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Snow volume: 4.47 m³
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Snow density: 492 kg/m³
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Total snow weight: 2,199.24 kg (4,848.50 lbs / 2.199 tonnes)
These results confirm the structural integrity of Keder cladding under substantial snow load.
Light Diffusion
Keder cladding offers advanced light management through its unique multi-layered bubble design. Each square foot contains over 100 sealed air bubbles that scatter up to 83% of incoming light - including 30% beneficial infrared light.
This even light diffusion eliminates hot spots and shaded zones, creating a uniform growing environment that supports healthy plant development.
Additionally, Keder’s design helps moderate internal temperatures - reducing heat during the day while retaining warmth at night - and its insulating properties help minimise condensation.
Lower Heating Costs
The built-in layer of sealed air within Keder sheeting provides exceptional insulation and thermal retention. When compared to traditional glasshouses, Keder-clad structures can reduce heating costs by up to 50%, making them a more energy-efficient and cost-effective solution for year-round greenhouse growing.