General information about plastic films for greenhouse
Many people think that every films for covering the greenhouse is the same, or perhacan increaseps they are just different about size and thickness. This thoughts are totally wrong. Because if you choose a suitable plastic film for your own greenhouse you crop productivity in a short time and maximize profit as well. Hence, the first step of all is finding the right type of film covering your greenhouse.
When we are concerned about building a plastic greenhouse, sunlight is an invaluable and free resources. So, any plastic film you choose must be able to utilize the best usage of daylight.
utilizing the daylight is a good factor of plastic films
The second factor you need to care is the condensation on the greenhouse’s roof. It is working such as a mirror which will reflect all daylight away from your green leaves. In fact, many people do not think about it as a problem. Because these water drops will be supposed to evaporate at noon and the sun ray continues to get inside the greenhouse at the same time. However, they don’t know that the best sun ray is in the early morning only. At noon, their green leaves will shut down and don’t take benefits from sun ray in order to produce energy for using at night. So, waiting until all water drops evaporating is just wasting your time.
The third factor to find a good plastic film is a capacity of keeping heat at night and save energy for your whole greenhouse. That means the bottom layer of these film should be made with AC and the IR to decrease the loss of re-radiation at night.
Three types of plastic film you should concern for greenhouse
Polyethylene Film
People also call it as PE film. This kind of film is the most lightest among films for applications in agriculture. Producers make it in the rolling form, so it is easy to fit for your roof. This one-layer film is the cheapest and thinnest type. Of course, it is an inexpensive option but not necessarily a good choice for long term.
Another point is that UV light will quickly degrade PE film, so you should buy a plastic film attached UV protection and more one layer.
Double Walled Plastic
Using double wall plastic means that you are installing a double layer film. Hence, you can raise strength for your greenhouse to resistant against bad weather twice. However, supplying air by a fan between the layers to keep them from stick together is recommended. Light transmission through the two-layer plastic film reduce about 70%.
Double-layer plastic film will be usefull in terrible weather
Polycarbonate film
The special feature of this plastic film is that it allows the sun ray going into the greenhouse more than 90%. So, you understand that it is helpful to utilize your daylight best. Moreover, polycarbonate film is so suitable for installing on the roof of your greenhouse. It also has two layers, such as cardboard box form, and its lifetime would be up to 15 years. That is the reason why its price is not cheap at all.