Introduction to roof greening
Roof greening popular speak is not connected earth gas plants, it is often said that the hanging gardens, in the city has been known as the roof greening. Actually the roof greening not only roof greening and roof greening, greening on the overpass, artificial rockery also belong to the roof greening. Roof greening is one of the most effective ways to heat insulation and heat insulation, but also one of the important ways to restore green space.
At present stage, the maximum resistance and problems of roof greening
There are 4 main points of resistance and problems, but the basic technology is not mature.
1, the green roof waterproof
The main reasons for the leakage of housing are: waterproof layer damage, housing cracks, do not have the place of waterproof long-term water immersion. Housing cracks are housing quality problems, the roof has been equipped with the capacity of the floor, even if the water is not in the indoor leakage. So as long as the quality of the housing problem, the roof of the waterproof problem is to prevent the relevant waterproof layer is destroyed. Therefore, in plant selection or increase the corresponding protective measures can be completely resolved the problem, the choice of plants must have a shallow root, no puncture ability of the plant, or by other means to prevent the plant root system on the building of puncture, damage. On the other hand, the roof greening avoid slab is direct sun exposure, and roof insulation effect, greatly reduces the thermal expansion and contraction of slab, the temperature difference between day and night, prevent because of heat expansion and cold contraction brought slab rupture caused by seepage.
2, the roof greening engineering construction cost of
The common way of roof greening is: the roof gardens, the Roof garden, the roof garden and the roof lawn, the construction cost is also so from high to low. Roof garden construction cost is the most expensive, but also the most close to the natural ecology of a green roof, according to different plants, different ways of construction cost is generally 500 yuan to several thousand dollars a square meter. Roof garden in general in the district or some of the lower level of the implementation of some of the more high-grade, the construction cost is about 300 yuan per square meter -600 yuan. Roof garden in addition can be used as green roofs can also produce vegetables, can let you in the spare time personally experience the fun of growing their own vegetables. The construction construction costs about 200 yuan per square metre about 400 yuan. The most cheap and maintain the same green effect of roof greening is the roof of the lawn, according to plant selection, construction process is different, the price per square meter is about 100 yuan -200 yuan. In addition to the cost of construction, more should be considered in its maintenance costs.
3, the green roof maintenance cost
Conventional garden style roof greening need to maintain management, due to the roof, the same area of maintenance management costs to be higher than the cost of ground greening, the most common and most inexpensive garden style roof greening maintenance costs of about 5 yuan a year, a little luxury point of maintenance costs is more than a year 20-100 yuan a square meter. In such a way that a large area of the promotion is clearly unrealistic, low cost and low maintenance costs are the only way to promote the high efficiency of urban roof greening! Roof lawn becomes the first choice, the maintenance cost per square meter per square meter of the roof is basically within 1 yuan, the roof of the lawn Kam bamboo grass is close to 0 maintenance costs.
4, the green roof bearing
Standard housing floor average load capacity of about 200 kilograms per square meter, some commercial buildings can reach 300 kilograms per square meter, some of the old building capacity of about 100 kilograms per square meter. Roof garden average per square meter of weight at least 300 kg or more, the average weight per square meter of Roof garden is 150 kg -200 kg, the roof garden an average weight of 60 kilograms per square meter of -100 kg, the average weight of 20 kilograms per square meter roof lawn. That is to say, the roof of the lawn in the ordinary tin shed, asbestos can be laid on the roof! So the roof garden and the lawn of the roof is not the basic problem.
The function and trend of roof greening
1, roof greening can be a roof insulation or roof insulation, in the hot sun exposure of the floor temperature of 55 degrees -60 degrees, equivalent to a huge high temperature heat to the indoor heat. Is not only a waste of indoor air conditioning electricity, but also easy to cause the expansion and contraction to slab rupture, the use of plant as the roof insulation, floor temperature can be decreased by 10-15 degrees, not only insulation roofing well, but also for the greening of the city out of a force, benefit is not only insulation roof top layer of the residents, is to reduce urban air pollution and heat island effect and benefit to the public.
2, green roofs can be on the top of the building has a protective effect, prevent the thermal expansion and contraction caused by the cracking of floor plate, to prevent the erosion of acid rain on the building, reduce the harm of building weathering.
3, the roof is absorbed and accumulated a lot of solar radiation heat, is the city href= "heat island effect". Because the roof greening plants can absorb and digest the solar radiation heat, so as to play the role of heat insulation and energy conversion.
4, the roof greening can absorb carbon dioxide, sulfur dioxide and other gases; adsorption of dust in the air, effectively reduce the content of solid particles in the air. To purify air and improve air quality.
5, the roof can be converted to green 30-50% green rate, to solve the problem of building or factory green rate is not enough.
On the ground more difficult to find a suitable large green land, and the cost of the roof greening, the use of ground to do green, a square meter of land costs on a few thousand yuan, and the vast majority of roof almost 100, as long as the cost per square meter of 0 yuan per square meter (-500 yuan), not only can improve the green area, by the roof heat insulation of the top users will be the biggest beneficiaries, we will actively cooperate with the roof greening, roof insulation. Urban roof area of about 20% of the city's size, if fully prepared to do a green roof, will be a substantial increase in the city's green area.
Some real estate developers in the South have in the roof of their building do the roof greening and heat insulating and great praise after the roof greening and heat insulation by the owner, also makes the top floor of the house sell higher price. In the people's awareness of the green and the government's attention to participate in the promotion, the roof greening will be the focus of the next step of the city.
Large areas of the implementation of the roof is the fundamental to the implementation of low cost, low maintenance costs, effective programs, roof lawn just have these 3 characteristics, is a large area of the first choice for green roof.