Many gardeners are considered one of the most necessary items on the site of the greenhouse. This is especially true for areas with a long winter. The greenhouse is needed for obtaining early harvests, growing seedlings, fast growing plants and protecting them from adverse weather conditions in early spring or autumn.
Everyone chooses a greenhouse for their own taste: someone builds it from wooden bars and covers with plastic wrap, someone uses glass or window frames, as described here. But most have already appreciated the merits of modern material - polycarbonate. It has long been produced various types of greenhouses, differing in size, shape, features of materials, prices. How to understand this diversity and choose the optimal design for your needs? To do this, you need to get acquainted in more detail with the types of greenhouses and their characteristics.
Features of polycarbonate as a material for coating the greenhouse
Polycarbonate is a solid, transparent two-layer polymer material with a number of advantages over other options for hothouse glass coating and film:
- high strength( polycarbonate is 200 times stronger than glass, and PVC and acrylic plastics in8 times);
- durability( warranty period of products is usually 10-12 years);
- lightness( this material is lighter than glass 16 times, acrylic of the same thickness - 3 times);
- high light transmission( up to 86% transparency);
- low thermal conductivity;
- good thermal and fire resistance( withstand temperatures from + 120 ° to -50 °);
- chemical resistance;
- resistance to weather and atmospheric phenomena;
- protection against UV rays;
- security coverage;
- excellent construction capabilities.
When installing a greenhouse made of polycarbonate, certain conditions must be observed:
- if the sheet is fixed inside the UV protective layer, the coating will last only 2-3 years, since moisture accumulating on the inner surface will destroy the coating;
- polycarbonate has a honeycomb structure, hollow inside, so its bending during installation must be done in a direction perpendicular to the internal channels;This is done so that the water that gets inside does not accumulate and flows down;the ends of honeycomb polycarbonate are usually sealed with special sealing tapes and end profiles.
If you do not comply with these conditions, the appearance of polycarbonate can quickly deteriorate, and its service life will be shortened.
Types of greenhouses
The most common types of greenhouses coated with cellular polycarbonate are arched and tent( gable, "house").All other varieties are variants based on these two.
Arched greenhouses are characterized by low cost, lower consumption of polycarbonate. Their streamlined, round shape, which does not have sharp corners, facilitates installation, reduces heat loss, gives good resistance to wind. But because of the small height of the outermost beds such greenhouses are better to use for low crops.
Tent greenhouses can be used for any plant, and therefore they have maximum functionality. They can have non-standard sizes and designs, can be built independently. The walls are straight, the corners of the roof slopes can be 25-30 °.But for such greenhouses a stronger frame is needed, since the snow load increases. In addition, more polycarbonate goes to the greenhouse of this design, which means that it will have a higher cost.
Features of the frame
For the manufacture of the frame of the greenhouse has traditionally used several types of materials, among which the most popular steel rectangular pipe and steel zinc-plated profile.
The steel pipe for the frame is usually taken with a cross section of 30 × 30 mm, it can be galvanized or coated with paint. Such a frame is very durable, withstands heavy loads in winter. But painted frames are not an optimal choice: because of the high humidity in the greenhouse and the condensate drain, the paint may soon collapse and rust appear, especially at the points of contact between the carcass and polycarbonate. This, of course, does not add to the aesthetics and strength of the greenhouse. The frame made of galvanized pipe does not rust for several decades, but it is very heavy and expensive.
Tips for choosing a greenhouse
When choosing a polycarbonate greenhouse, pay attention to some tips:
- The thickness of polycarbonate should be at least 4 mm. Ask the seller directly about this. Any material of lesser thickness, even 3.8 mm or 3.5 mm, is of poor quality, it will not last long.
- Be sure to find out if the protective layer is applied from the ultraviolet. No additives in the raw materials! Such a coating will collapse in 2-3 years.
- If the seller tells you that a greenhouse of fine quality, although cheap, you should not believe. Good quality is expensive. And you will lose more when you have to acquire a new greenhouse in exchange for the destroyed one or two years later.
