Do-it-yourself green roof - technology and features

The primary task of the roof structure is protection from cold air, snow, rain or other atmospheric phenomena. However, the lack of space for construction, the poor ecology in cities, the poor quality of crop products make it necessary to impose additional functions on the roof, introducing innovative architectural solutions. One of the most relevant trends in ecological housing construction is considered to be a vegetable roof, on which you can break not only the lawn, but also a real vegetable garden, where you can grow healthy and safe fruits or vegetables. In this article we will discuss whether the green roof can be equipped with your own hands.

History

Roofs on which grass or other plants grow is a completely new invention. Although even more ancient specimens of this architectural tradition are known, the most illustrative example of the use of plant roofs are the sod dwellings of Icelanders, who date back to the 18th century. Moss-covered houses are a characteristic feature of peoples living in the territory of modern Norway, Canada, Great Britain, Switzerland.

Residents of the camp, which are characterized by a harsh, cold, windy climate, immediately noticed that the roof covered with vegetation better protects against low temperatures, retains heat inside the house, forming inside the dwelling a pleasant microclimate. In modern conditions, eco-roofs used for planting a lawn or breaking a mini-vegetable garden are rather a fashionable trend that allows you to take care of nature, your own health and rational organize living space.

It is interesting that in modern megacities, where the level of air pollution and stress exceeds all reasonable limits, it is necessary for a person to organize green recreational zones. Even in the projects of Soviet modernist architects, eco-roofs appeared, designed for walking, relaxing, or locating greenhouses that could provide residents with fresh greenery year-round.

Virtues

Widespread landscaping is a prerequisite for comfortable living in modern metropolitan areas built of glass and concrete. However, often in cities, chained in asphalt, there is simply not enough space to accommodate green areas. The way out of the current situation is the green roof, which allows not only more rational use of living space, but also significantly improve the ecological situation. The advantages of this technology include:

1. Durability. The plant layer, covering the roof surface tightly, protects the roofing material from mechanical damage, temperature drops, moisture, so it will last more than 20 years.
2. Rationalize the use of rain moisture. Green spaces located on the slopes of the roof, hold more than 25% of precipitation, preventing spontaneous flow of water, flooding. Instead of aimlessly merging into storm sewers, water is used for irrigation, nourishing the crop.
3. High insulating properties. The layer of soil and turf eco-roof serves as an excellent insulating material that helps to maintain a comfortable temperature inside the dwelling and protects it from external noise.
4. Organization of additional living space. Green roof can be a place for recreation, sports in the open air, swimming pools and even a cafe.

But the most important thing is that the technology of eco-roof arrangement allows to improve the ecological situation in totally gassed megalopolises, to preserve and increase the health of modern man.

disadvantages

Despite the obvious advantages, the technology of green eco-roofing has not yet become widespread. This is primarily due to the high complexity of installation and the large amount of costs for installation and maintenance of the structure. The disadvantages of vegetable roofs are considered to be:

• Great weight. The layer of drainage, soil and plants adds up to 50 kg / m2 of area, so the green construction significantly increases the load on the floors and the foundation of the structure.
• High price. For the device of an eco-roof it is necessary to use only environmentally friendly materials, so its installation is much more expensive than a regular pitched or flat roof.
• The complexity of installation. In connection with the heavy load on the foundation and floors, a project based on an exact calculation is necessary for the installation of a plant roof. Therefore, it is rather difficult to do this work with your own hands, most often you have to resort to the services of contracting organizations.

Note! Most experienced roofing masters and architects believe that it is dangerous to convert old roofs into vegetable ones, since the floors and the foundation may simply not withstand the additional load and give irreversible deformations.

Kinds

Depending on the height and purpose of the building, the types of plants used and the gardening objectives pursued, the eco-roof can change its appearance. It can be equipped with success both on pitched and on flat roof constructions. In accordance with the nature of use, the following types of plant roofs are distinguished:

1. Extensive. Extensive green roofs are called pitched structures covered with vegetable carpet, the slope of which does not exceed 45 degrees. Due to the peculiarities of the architecture, such roofs do not have exits, therefore they cannot be used. For gardening of roofs of this type, perennial low-growing green plants (moss, cereals, clovers) are used, which over time pull the surface, protecting it from mechanical influences and weather. It is quite simple to care for such constructions, since they are watered naturally.
2. Intense. Intensive eco-roofs are called flat structures related to the type being exploited. They are provided with access to the roof, a parapet that protects against falls and paths for safe movement, so they can grow not just a decorative lawn, but fruit-bearing plants that can be used as food. Naturally, vegetable roofs of intensive type require more attention during operation. In fact, such an “air” garden will have to be looked after as well as a hired one.

Important! In order for the green roof to please with its aesthetic appearance for a long time, it is necessary to carefully select plants that are well tolerated by the climatic conditions in the region where the construction is being carried out are not demanding to care. In addition, it is worth considering that the thickness of the soil layer is limited, so you should choose plants whose roots are not located vertically, but horizontally.

Structure

Eco-roofs also, like the ordinary ones in their structure, resemble a layer cake, however, their components are slightly different due to the nature of their operation. They must ensure the reliability of the design in the following areas: foundation strength, protection against water penetration, and prevention of heat losses. The roofing pie of vegetable roofs has the following structure:

• Base. The base of the roof can be woody or concrete, as long as it has sufficient safety margin to support the weight of the soil and plants.
• Waterproofing. To protect against moisture penetration on the base in a few layers with overlapping stack waterproofing material. Moreover, it should have increased strength.
• Barrier. On top of the waterproofing place a barrier for the roots, which should prevent the germination of plants below this level. Without this layer, the roots will grow into a waterproofing material, damaging it.
• Drainage. The drainage layer is necessary to rationally distribute moisture entering the soil. He retains some of the water, preventing the plants from drying out during dry periods, and sends the surplus to the drain.
• Filter. The filtration layer or geotextiles are spread over the drainage to limit the penetration of small particles that can clog it.
• Geogrid The geogrid does not allow the ground to slide down, to scatter from the wind. More often it is used if the slope is more than 25 degrees.
• Substrate. Fertile substrate is poured in a uniform layer with a thickness of 5-20 cm on the geogrid. A 5 cm layer of soil is enough to grow a lawn, but a depth of 20-25 cm is required to grow fresh cucumbers on the roof.

Note that the ground for the eco-roof should be light enough, but it is good to retain moisture. Landscape designers recommend using fine clay, peat and sand for relief. In addition, you should take care of soil fertility, adding organic and mineral fertilizers.

Plant selection

In order for the plant roof not to wither in the very first dry summer or not to freeze in cold winter, it is necessary to choose undemanding and winter-hardy plants that can exist well in a closed ecosystem. Landscape designers and plant growers recommend adhering to the following rules when selecting flora:

1. Small and horizontal root system. This criterion is optimally matched by mosses and cereals.
2. Frost resistance Plants should tolerate negative temperatures characteristic of the winter period.
3. Drought tolerance. It is necessary to choose plants so that they manage only with natural watering during rain.

Remember that exotic plants that are not characteristic of our climate zone require more careful care, so they can be planted only if you are ready for a large amount of time and money to ensure appropriate living conditions.

Video instruction