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How to help enhance thermal insulation in Commercial Greenhouse

There are many types of greenhouses in this industry, such as single-span greenhouses (tunnel greenhouses), and multi-span greenhouses (Gutter connected greenhouses). And their covering material has film, polycarbonate board, and tempered glass.

Picture-1-Single-span-greenhouse-and-multi-span-greenhouse

Because these greenhouse construction materials have different kinds, their thermal insulation performance is different. Generally speaking, with relatively high thermal conductivity of materials, heat is easy to transfer. We call the parts with low insulation performance "low-temperature belt", which is not only the main channel of heat conduction but also the place where condensate water is easy to produce. They are the weak link of thermal insulation. The general “low-temperature belt” is located in the greenhouse gutter, wall skirt junction, wet curtain, and exhaust fan hole. Therefore, taking measures to reduce the heat loss of the “low-temperature belt” is an important means of energy saving and thermal insulation of the greenhouse. 
A qualified greenhouse should pay attention to the treatment of these “low-temperature belt” in construction. So there are 2 tips for you to decrease the thermal loss of a “low-temperature belt”.
Tip 1: Try to block the “low-temperature belt” pathway that carries heat outward.
Tip 2: Special insulation measures should be taken at the “low-temperature belt” which conducts heat outwards.
 
The specific measures are as follows.
1. For the greenhouse gutter
Greenhouse gutter has the function of connecting the roof and rainwater collection and drainage. The gutter is mostly made of steel or alloy, insulation performance is poor, large heat loss. Relevant studies show that gutters occupy less than 5% of the total area of the greenhouse, but the heat loss is more than 9%. Therefore, the effect of gutters on energy conservation and the insulation of greenhouses can not be ignored. 

At present, the methods of gutter insulation are: 
(1) Hollow structural materials are used instead of single-layer metal materials, and air inter-layer insulation is used; 
(2) Paste a layer of an insulation layer on the surface of the single-layer material gutter.

Picture 2--Greenhouse gutter

2. For the wall skirt junction
When the thickness of the wall is not large, the external heat dissipation of the underground soil layer at the foundation is also an important channel for heat loss. Therefore, in the construction of the greenhouse, the insulation layer is laid outside the foundation and short wall (generally 5cm thick polystyrene foam board or 3cm thick polyurethane foam board, etc.). It can also be used to dig a 0.5-1.0m deep and 0.5m wide cold trench around the greenhouse along the foundation and fill it with insulation materials to block the loss of ground temperature.

Picture3-Greenhouse-wall-skirt

3. For the wet curtain and exhaust fan hole
Do a good job of sealing design at the junction or winter cover blocking measures.

Picture4--wet curtain and exhaust fan

If you want to take further information, please feel free to contact Chengfei Greenhouse. We focus on greenhouse design and manufacturing all the time. Try to let the greenhouses return their essence and create value for agriculture.
Email: info@cfgreenhouse.com
Phone No.: (0086) 13550100793


Post time: Feb-15-2023