What biased material is really effective, and what is not very? We offer to compare the main types.
Polyethylene
Polyethylene film as a means of protecting garden crops from the cold is well known to summer houses from Soviet times. Despite the fact that the choice of observer materials for greenhouses and greenhouses today is quite wide, it still did not lose its relevance.
The transmission ability of underfloor polyethylene ranges in the range of 80-90%, which affects the growth of vegetable crops. Some gardeners consider this parameter not high enough, but it is not. Absolutely transparent material is suitable for greenery, but it can harm vegetables: too much light is badly affected on the strings and the development of fruits. A similar negative effect of the oversupply of the Sun is manifested in relation to cucumbers, tomatoes and Bakhchyev, the fruits of which may eventually be at the weight.
Thanks to the film inside the greenhouse, the optimal level of humidity is always supported. At the same time, the temperature of the soil on the beds is higher than outside. Thus, a special microclimate is created, which contributes to the rapid ripening of plantations. They are not terrible frost, strong wind, degrees or fog with overvoltage.
The main disadvantage of polyethylene is poor resistance to mechanical damage: it can be accidentally pierced, break or cut. The level of wear resistance also leaves much to be desired. The cheapest material samples serve only one season, as the precipitation and sun rays quickly deprive his elasticity, because of which he loses the ability to resist freezing.
Cellular polycarbonate
Due to its cellular design, polycarbonate has increased strength and good heat-saving properties. Unlike a cheap film from polyethylene, it is resistant to the load on the gap, it does not damage from the wind and hail, is not afraid of random strikes. The transparency of the panels is 86%. At the same time, they do not lose their consumer qualities due to the effects of ultraviolet, since a special protective layer is applied on their front side.
The material can be used at any temperatures in the range from -40 to + 1200c, which makes it almost uninstalistic. No wonder the service life of the cellular polycarbonate is at least 15 years.
There are no serious deficiencies except higher (in comparison with film) prices, there are no cellular plastic panels. The main thing is to choose them to choose and mounted.
When choosing, first of all, it is necessary to take into account the total area of the greenhouse. If it is not very big (up to 30 m2), buying too thick plastic to anything, in this case should be closed to the panels with a thickness of 6-8 mm. For designs of up to 20 m2, polycarbonate is suitable thinner - 4-6 mm. The products of 10 mm thick and above are used for large buildings, from 40 m2.
As already mentioned, most panels have a protective coating from the negative effects of sunlight. At the same time, some manufacturers in order to reduce their products are not protecting it from ultraviolet. Therefore, when buying, you need to make sure that the material liked the material is really not afraid of the sun.
Quality polycarbonate is different from fake:
- Sheet thick. Standard transparent cellular polycarbonate for greenhouses has a thickness of at least 4 mm, and cheap 3-3.5 mm, about what sellers are often silent or, worse, deceive buyers and give such polycarbonate for the standard.
- The thickness of the inner partitions and the outer walls, and consequently, and weighing. Standard leaf for a greenhouse 6 m long should weigh 10 kg.
- The presence of high-quality protective film.
Nonwovens
Quite often on the gardens you can see the film from propylene. Externally, it looks like a multi-layer gauze from intertwined translucent threads. The most famous brands - Agril, Loutrasil and Spunbond. They are produced in different countries, but it is not necessary to navigate the manufacturer, but on the thickness of the material and its purpose.
So, the white and thin "no-knack" density of 17 g / m2 protect plants from pests and small frosts (up to - 20 ° C). Use it usually without any rigid base. But propylene is relevant (30-60 g / m2) is used already together with the case of frosts to -60c. At the same time, the thick (60 g / m2) of the black blade protects the crops from the intensive evaporation of moisture and suppresses the growth of weeds.
Nonwoven materials are distinguished by the fact that air, water and sun rays are passed in the dosage volume. For example, in the summer heat, the white polypropylene saves off the overheating, and the black (in the spring) does not give them to hypogly.
Unfortunately, propylene fiber, as well as polyethylene, does not have sufficient strength, quickly wear out and rushes. Most often it is used as a mulch, less often - as a full shelter on a rigid frame.
Glass
Glass greenhouses are traditionally used in all regions, regardless of geographical location and climatic features. And this is understandable: glass as material to protect plants from external factors has a whole set of advantages. Among them are excellent light transpact properties, and good thermal insulation, and the ability to withstand significant snow loads. In addition, the glass sash that has become unusable can always be quickly replaced.
Of course, there are cheaper ways to build a greenhouse. However, if the old windows remain in the barn, the old windows are dusting, then they do not find better use. Especially since the use of them for construction is an excellent way to save.
Frame is easiest to collect from the tree. To do this, you will not need to acquire special equipment, as the wood is processed very easily. Accordingly, there will be no problems with the connection of the elements. There should be no lack of materials, since there are always some billets that can be useful in the work.
Do not drop old window frames from accounts. They will significantly save the family budget and serve as a carcass for the greenhouse. It is also worth noting the fact that old frames exhibit outside when replacing new windows and you can pick them up completely free.
If a durable design is needed, it makes sense to order a ready-made glass greenhouse with an aluminum profile frame.
Advice
- In the construction of greenhouses, the ends of the polycarbonate sheet must be protected from the penetration of moisture with special plugs.
- With sudden temperature drops, plastic may narrow or expand. If in the process of installation does not take into account this circumstance, the material will crack and cease to be sealed.
Andrei Kartsev, Dachnik:
Spend lighting to the greenhouse. Everyone knows how an additional backlight is important in greenhouses for the future harvest, but energy consumption for nutrition of sources emitting red light has not led to the dissemination of this reception in practice. In the cultivation facilities of the closed soil, this obstacle is eliminated by the use of underfloor materials (organic glasses, for example), which introduced special additives (phosphors) capable of converting a portion of solar radiation into a red light that stimulates the reactions associated with the Emerson effect.
The article was published in the journal "Tips of Professionals" No. 12 (2017). Subscribe to the printed version of the magazine.