A greenhouse is basically a building for plants to grow and live for a longer lifespan. It is also termed as glasshouse where natural light can pass through the windows providing natural brightness during daytime. Greenhouses vary in terms of structure and size. Some are built like small sheds while others are built as large buildings. There is also a so-called miniature greenhouse or mini greenhouse which is commonly known as cold frame.
The structure of a backyard greenhouse differs in terms of covering materials used. Examples of these are glass, plastic roofing, polycarbonate and plastic walls. Greenhouses which are made of glass usually heat up because the transparency of the glass allows the solar radiation coming from the sun to enter and be absorbed by the plants, flowers, soil, and other objects inside the building.
In most cases, where a greenhouse is situated in warm areas, the interior surface of the building will certainly absorb the heat coming from the sun. In effect, the plants and warmed structures inside the greenhouse will have re-radiation reaction and will produce thermal energy.
An opaque-structured greenhouse will have the energy trapped inside the building. This type of greenhouse however, is not commonly used as compared to the conventional type of glass house. It only applies to some greenhouse owners who are concerned about growing unique species of plants and flowers with the element of the weather condition.
Primarily, the heating mechanism of a greenhouse is called convection. This process is explained by making a small window at the roof of the greenhouse. This window allows air to enter into the greenhouse causing a considerable drop of temperature. The concept of having a small window or opening is based on the principle of the automatic cooling system or auto-vent. Hence, the glass structure of the greenhouse serves as a barrier to airflow which meets the objective of trapping the energy inside the greenhouse. As such, the warmed air close to the ground is blocked from rising and flowing away.
Types of Greenhouses
There are two types of greenhouse and these are glass greenhouses and plastic greenhouses. Plastic greenhouses are usually made of multi-wall sheet and PE film. These commercial types of greenhouses are made of high-end materials and facilities that promote quality growth of vegetables and flowers.
The advent of technology also provided high-tech features on today’s greenhouse structures. There is equipment used inside the glass greenhouse such as lighting, heating and cooling systems and screening installations which are automatically computerized. There are greenhouse kits on the market that are innovative and easy to assemble. Another type is the “Push and Fit” greenhouse with connectors which can be assembled according to the size and build that the owner needs.
Portable greenhouses are also available. This type of greenhouse can be transferred from one place to another, such as a garden or open backyard area, and can also be used for a desired season. Buying a greenhouse can be a choice between the traditional and cheap type or the high-quality and expensive kind. The more durable ones are made of strong and quality materials and that is why a higher price is also expected.
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