When choosing a cover for a greenhouse, we pay attention to the cost of the material, its quality, reliability and practicality. Of course, there are many expensive options, but they are not always available to us. And what remains? The film for greenhouses, which has been known to us for many years. This is not the best choice among modern materials, but here you can always save a little.
Despite the low cost of the material, we want to get excellent quality, which will allow the use of a film greenhouse at least 5-7 years before replacing the cover.
It is not easy to choose a covering for a greenhouse construction in our time. This is due not only to a large selection of such products on the market, but also to the decency of some sellers, who often sell cheap film at an expensive price, calling it the same name. The material falls into the hands of the summer resident, settles in place and serves only a year or two - that’s the reason for the bad reviews. But if you search well and learn how to choose the right material, paying attention to its advantages, you can find a reliable option with a long service life.
Today, we know of four main types of film coatings that are used for greenhouse structures. Let's look at each of them in order.
Plastic film for greenhouses
The most popular and inexpensive on the market. It has been in great demand since a long time, of course, only for the sake of economy.
The material is produced in rolls, the width of which is 1.2-3 m. It can be produced in the form of a uniform canvas, or maybe in the form of a sleeve. The latter type is used in different ways. You can cut the sleeve in a straight line and get the canvas exactly 2 times wider than the previous one, or you can cover the greenhouse with the sleeve. But this does not mean that a double layer will significantly increase the service life of the coating. Another unpleasant moment is the bending of the sleeve, which becomes unusable in the first place. This situation can be prevented in advance if you pass along the entire length of the bend with a dense transparent tape.
Choose, transport and stretch the material carefully to the frame of the greenhouse or greenhouse, as any cut or crack can become a strong accelerator of its “death”. You should not take a very expensive and thick plastic film for covering, it still will not last you more than one season, although it can survive until the coldest weather if you live in the region of arid winds and the scorching sun. Otherwise, polyethylene is only enough for the season, because cold and rain, wind and hail, the sun and temperature changes will quickly spoil the material.
Video - light stabilized film for greenhouses
Reinforced film for greenhouses
It is made of high density polyethylene with an inner frame that takes up the bulk of the load. This is a cellular material whose thickness is different for every few centimeters, therefore its quality is determined not by thickness, but by density. On the market you can find goods of various manufacturers and different quality, but the most common is reinforced film with a density of 120-200 g / m².
The film frame is made of polyethylene of various processing methods. It can be fiberglass, polypropylene, low pressure polyethylene, extruded, stretched or twisted polyethylene. If we consider the manufacturers, then the domestic market is dominated by Korean, Danish and Russian films. Each of them is distinguished by its cost and technical characteristics, many of which remain controversial. You can also find a breathable reinforced film for greenhouse structures, which is distinguished by the presence of holes in the cells. This fact allows the greenhouse to be simultaneously airtight and not “preserve” the air inside.
Most often, manufacturers promise a long service life, sometimes up to three years, but as usual, it all depends on the conditions of use. A denser film under conditions of a rare change in temperature will last longer, and a less dense film in more severe climatic conditions, respectively, less. But whatever you may say, the reinforced greenhouse film has every chance of serving the greenhouse for several seasons, in contrast to ordinary polyethylene coating.
Polyvinyl chloride film
There is an opinion that the PVC film is very similar in structure to cellophane, but this is slightly different. You will be able to verify this yourself when you compare the film for greenhouses with a wrapper for flowers (which is cellophane). At this point, you will notice that these materials differ in thickness and density.
PVC film has a good light transmittance - more than 90%, the ability to transmit more than 80% of ultraviolet radiation and retain about 95% of infrared radiation. It retains heat well and does not allow the greenhouse to cool quickly at night, which is very good.
The coating has excellent quality indicators, due to which it can last up to 5 years in the most difficult conditions. If favorable conditions are created for the greenhouse, then the film can last more than 7 years. The only negative of this material is the high price, but this is also a controversial issue. Carefully recount the costs of ordinary polyethylene, labor hours for dismantling the old film and stretching the greenhouse for a new one, and so on, it may turn out that the PVC material is not so expensive.
Perennial greenhouse films
This definition contains many varieties that have different qualities. This can be a light-stabilizing film, and heat-retaining, with the effect of light conversion or hydrophilic. Quite often, manufacturers combine some of the characteristics in one product. In this case, it turns out quite expensive, since in addition to a wide range of advantages, it is also of high quality and long-term. But also often under the list of multifunctionality and a considerable number of technical characteristics, a standard film for greenhouses can be put up for sale, with the expectation that it will be purchased by an inexperienced summer resident.
The set of perennial films includes copolymer, foam, and even air bubble, which is intended for use only under certain conditions. But sellers, as well as manufacturers, rarely indicate the conditions of use, and attract attention only to the advantages of the material sold, which are often not needed at all in some regions.
So, how to choose the right film for a greenhouse? How to equip the hotbeds with the coating that will last for many years, provide plants with normal life and will not cost very much? The answer, probably, is only one - to be extremely attentive and very demanding at the place of purchase.
Choose the material based on quality and service life, always ask the seller for supporting documents, carefully calculate not only the cost of the goods, but also translate the price in the years of service. It often turns out that in appearance the expensive film is several times cheaper, since it lasts longer and does not require replacement every year. Be careful, make the right choice and then your greenhouses will bring excellent harvests!