On the planning and design of roof garden?

2 1 century today, with the increasing density of urban population, modern architecture has also increased. With the increase of buildings, the area of large green space has decreased sharply, and the corresponding environmental conditions have deteriorated, which has made people pay more attention to the environment than ever before. It can be seen that in the process of urban development and construction, making full use of all green spaces and increasing the area of green spaces, "green is everywhere". Even so, it still fails to achieve people's expected purpose. Modern buildings are mostly flat-roofed houses, and the roofs are reinforced concrete precast slabs. The modern construction method is to make thermal insulation and waterproof layer on precast slab. Seen from the air, the buildings seem to be wearing black hats, and the residents living on the roofs also suffer from asphalt, leading a hot life in Leng Xia in winter. In the past two years, many people began to build roof gardens to make the lifeless roofs full of vitality. In this case, using the roof of the building to open up the garden green space and build the roof garden has become the most promising, effective and direct measure to restore the green space, so it is widely used.

1 History and Present Situation of Roof Garden

Roof garden is not the product of the development of modern architecture. It can be traced back to 4000 years ago. The templo mayor Tower, built in Ur, one of the oldest Sumerian cities, is the birthplace of the rooftop garden. In the early 1920s, the famous British archaeologist Lund. Sir Woolley found traces of trees planted on the third floor of the tower. The real roof garden is the famous Babylonian "hanging garden" discovered more than 500 years after the ancient Assyrian temple tower/kloc-0. It is listed as one of the "Seven Wonders of the Ancient World" by the world, and its significance lies not only in the achievements of gardening art, but also in the masterpieces of ancient civilization. The Hanging Gardens in Babylon were built in 604-562 BC. King Nebuchadnezzar II of new Babylon married a beautiful Persian princess, Princess Semiramis, who missed her hometown day and night and was unhappy. In order to please her, the king ordered a mound to be built in Babylon in the plain area, and a platform with a length of1.25m and a height of 25m was built on the platform to plant flowers and trees everywhere. Building a "hanging garden" in Babylon consumed a lot of manpower, material resources and financial resources, which was enjoyed by the royal nobles and embodied the luxurious life pursued by ancient emperors. In the following 2500 years, no real roof garden was built except for the greening of roofs in individual areas and the greening of underground garages in downtown business districts.

Since 1960s, western developed countries have successively built roof gardens and roof greening projects of various scales, such as the roof garden of Watergate Hotel in Washington, USA, the roof garden of Standard Oil Company in America, DT&; The roof gardens of T Company, Irish Life Center, Kaiser Resource Building in Vancouver, Canada, Dental Clinic in Hoya, Germany, Japanese Women's University Library, Taikoo Shing Garden in Hong Kong and Kwai Fong Garden in Hong Kong were all built on the roofs together with the architectural design, and most of them spread to the sky on the roofs or roofs of large public buildings and residential buildings. At present, roof gardens are not castles in the air abroad. In order to reduce the urban heat island effect, Chicago is promoting a roof garden project to cool the city. Tokyo, Japan expressly stipulates that as long as the new building area exceeds 1000 square meters, 1/5 of the roof must be covered with green plants, otherwise the developer will have to accept a fine. Some cities in China, such as Shenzhen, Chongqing, Chengdu, Guangzhou, Shanghai, Changsha, Lanzhou and Wuhan, have developed roofs. Such as: Guangzhou Oriental Hotel Roof Garden, Guangzhou White Swan Hotel Indoor Roof Garden, Shanghai Hua Ting Hotel Roof Garden, Chongqing Quanwai Building, Shaping Hotel Roof Garden, etc. Some cities have taken the roofs of urban buildings as new green sources. However, for many years, there has been no standard mode and standard technology in the construction of roof garden, so many defects and deficiencies have been exposed, such as long-term seepage prevention, soil erosion, serious pollution, unreasonable plant configuration, excessive load and high construction cost. With the development of science and technology, these problems will be solved step by step.

2 the function of the roof garden

Roof greening can increase the area of urban green space and improve the deteriorating human living environment space; Improve the present situation that natural land and plants are replaced by high-rise buildings and hard pavements of many roads in the city; Improve the urban heat island effect caused by excessive deforestation and various waste gas pollution and the harm of sandstorms to human beings; It is of great significance to develop human green space, build garden cities, improve people's living conditions and quality of life, beautify the urban environment and improve ecological effects.

2. 1 Ensure the ecological balance and good living environment of the living environment within a specific range.

A green roof is a natural air conditioner: in recent years, with the gradual increase of urban buildings, the accumulation of building energy caused by solar radiation is also increasing, coupled with the continuous increase of energy from household fuel, industry and motor vehicles, the energy surplus of urban climate is amazing, especially in summer, compared with areas without buildings, the temperature of cities is obviously higher, while in urban areas with dense buildings, unbearable high temperature will occur in summer due to lack of water. Due to the low light reflection of buildings, the temperature drop at night will be weakened, which will have a long-term negative impact on people's health. Green belts and green roofs can reduce the natural radiation by about 80% by moisturizing the soil and planting plants, thus reducing the side effects brought by buildings.

Experiments show that compared with the green roof, the green roof can cool down. In hot summer, when the temperature is 30 degrees, the ground without greening has reached an unbearable 40-50 degrees, while the base temperature of the green roof is 10CM, which is a comfortable 20 degrees. In winter, the green roof protects the building like a warm cover.

2.2 Protection of Building Structure Layer

In flat roof buildings, the damage of roof structure is mostly caused by the temperature stress of roof waterproof layer, and a small part is caused by load-bearing objects. The change of temperature will cause the expansion and contraction of the roof structure, cause cracks in the building and lead to rainwater infiltration. Form a loophole. China's "Construction Engineering Quality Management Measures" clearly stipulates that the warranty period of building roof waterproofing is only three years. So it is necessary to renovate the waterproof layer of the roof.

The rapid change of temperature is especially harmful to buildings. For example, in winter, after a cold night, during the day, the temperature of the building surface suddenly rises in a short time, and before that, the objects in the building are still frozen; In summer, after the temperature drops at night, the building surface temperature will increase obviously during the day. Due to the change of temperature, building materials will bear great load, reduce strength and shorten life. If the roof is afforested, it can not only adjust the extreme temperature in Xia Dong in two seasons, but also protect the building components. Therefore, roof gardens can protect buildings and even extend their life.

2.3 Roof greening can reduce roof drainage and reduce the pressure of urban drainage system by storing water.

Usually, in urban construction, the surface water will form a closed layer due to buildings, and the water falling on the surface of buildings will be led to the drainage ditch through drainage devices, and then it will be either transported to the clarifier or directly transferred to natural or artificial drainage facilities. This common practice will lead to a large reduction of groundwater, followed by a continuous increase in water consumption, and the final result of this vicious circle will lead to a serious depletion of groundwater resources.

Compared with not building a house on the ground, a lot of precipitation can't be discharged in a short time, which will definitely cause the harm of urban waterlogging, such as Zhengzhou. Roof greening provides the possibility of storing precipitation, reducing the pressure of urban drainage system and significantly reducing the cost of sewage treatment.

In many modern cities and regions, roof water is not used as a valuable natural resource, but mixed with seriously polluted water for wastewater treatment, which is quite expensive in sedimentation tanks.

When many roofs are mostly afforested, roof drainage can be greatly reduced. Experiments show that roof greening can reduce the precipitation intensity by 70% (Badelia Horticultural Station in Veitshoeheim), which can undoubtedly be used as a basis for saving money when determining the size of sewer pipes, overflow pipes or storage tanks in drainage projects.

2.4 The green roof has water storage function.

In addition to roof drainage, green roofs can store a lot of precipitation. Experiments show that about half of the precipitation stays on the roof, exists at the grass roots or evaporates through plants.

In foreign countries, many towns have begun to calculate the sewage cost separately from surface water and sewage, and for some closed areas, roof greening at least provides the possibility of saving money. Roof greening, considering surface water, can only spend half the cost in most cases. Sewers and water storage tanks can also reduce the load due to reduced roof drainage.

2.5 Roof greening can make natural precipitation seep into the ground.

The green roof system itself cannot leak surface water, because the superstructure and substructure of the building system are closed, so the water on the roof should not be led to the sewer, but let it seep into the ground or evaporate to form groundwater and natural water again. It can be seen that roof greening is a good start to improve the urban ecological environment.

3 planning and design of roof garden

3. 1 guiding ideology

Fully integrate local culture into garden landscape and garden space; Choose garden plants according to the influence of roof on garden plants; Use different gardening techniques to create a garden landscape that originates from nature and is higher than nature; People-oriented, give full consideration to people's psychology and behavior purpose, and plan and design the roof garden.

3.2 Design principles

The key to the success of roof garden lies in reducing roof load, improving planting soil, roof structure type, plant selection and plant design. When designing, you should do the following:

3.2. 1 Give priority to plant landscaping and ecological functions.

3.2.2 Ensure that the added load of the roof garden does not exceed the bearing capacity of the building structure, and the roof waterproof structure can be used safely.

3.2.3 Because the roof garden is relatively small compared with ground parks, gardens and other green spaces, it must be carefully designed to achieve the ideal artistic effect.

3.2.4 Try to reduce the cost. Judging from the existing conditions, only a reasonable cost can make the roof garden popular and blossom everywhere.

3.3 characteristics

The elements of roof garden are mainly natural landscape, various buildings and plants, which form a beautiful landscape according to the basic laws of garden beauty. However, because its gardening in the limited area of the roof is limited by special conditions, it is not completely equivalent to the garden on the ground, so it has its particularity. Roof gardening, all gardening elements are limited by the limited load on the top floor of the building. Therefore, the roof garden cannot be equipped with large natural landscapes and stones. When setting small stones, the bearing range of the roof of the building should be considered. Terrain treatment is mainly flat land treatment. Pools are generally shallow pools, and fountains can be used to enrich the water features.

3.4 Types of Roof Gardens

The construction of roof garden is not only the art of gardening, but also involves many technical problems different from open garden, such as structural bearing, roof waterproof and drainage structure, plant ecological characteristics, planting skills and so on. The types and forms of roof gardens can be divided into three categories according to the requirements of use.

3.4. 1 gong * * * Leisure Roof Garden

This roof garden not only has greening benefits, but also is a public place integrating activities and entertainment, so its publicity should be considered in the design. Attention should be paid to meet the needs of people's activities and rest on the roof in the aspects of entrance, garden road, layout, plant configuration and sketch setting. Lawns, small shrubs and flowers should be the mainstay, and a small number of chairs and small garden pieces should be set up for embellishment. The garden road should be wide to facilitate people's activities.

The roof garden built in the hotel has become one of the components of luxury hotels. It is actually a place to attract customers and provide nightlife. The roof garden can be set up with open-air song and dance parties, cold drink teahouses and so on. This roof garden needs to put teahouses for economic purposes, so the layout of the garden should be small and exquisite, ensuring a large space for activities, and the plant configuration should be mainly high-grade and fragrant.

3.4.2 Family Garden with Small Roof

With the development of modern social economy, people's living conditions are getting better and better, and the emergence of multi-storey stepped residential apartments makes this small roof garden enter the family. This kind of small garden is small in area, mainly plants, and generally has no sketches, but it can make full use of space for vertical greening, and can also carry out some interesting planting to appreciate the farmers' feelings that the city has long lost.

Another family-style small roof garden is the roof of the company office building. This small garden is mainly used as a place to receive guests, negotiate business and rest employees. This kind of garden should plant some rare flowers and plants and decorate some exquisite sketches, such as small waterscape, small rattan frame and small gazebo. You can also make miniature sculptures and small murals reflecting the spirit of the company according to your strength.

3.4.3 Roof Garden for Scientific Research and Production

Roof gardens can be equipped with small greenhouses for scientific research and production, and can be used to cultivate rare flower varieties, introduce flowers, cultivate ornamental plants and potted fruits. There are both greening benefits and good economic income. Generally, this kind of gardens should have necessary facilities, regularly arranged planting ponds and sidewalks to form a closed and integrated carpet planting area.

3.5 Overall layout

The form of roof garden is the same as the garden itself, and its creation is still divided into natural, regular and mixed.

3.5. 1 natural garden layout

Generally speaking, the layout of natural gardens, the organization of garden space, the treatment of landforms and the arrangement of plants are all natural methods to achieve the continuous combination of natural landscapes. Pay attention to the harmonious relationship between the natural form of plants and architecture, landscape and color, and pay attention to the four seasons ecology of flowers and trees in plant configuration, with height as the height and density as the degree. The pursuit is the change of color, the richness of levels and more landscape contours.

3.5.2 Conventional Garden Layout

The regular layout pays attention to the decorative landscape effect and emphasizes the change of dynamics and order. The arrangement of plants forms a regular, hierarchical and alternating combination, showing a solemn, elegant and grand atmosphere. Use more plants with different colors, and the landscape effect will be more eye-catching. In the regular layout, the roof garden is decorated with exquisite sketches and combined with plant patterns, which can often turn the narrow roof space into an area with rich landscape and broad vision.

Mixed garden layout

The mixed garden layout pays attention to the coordination and unity of nature and rules, and obtains the harmony of the landscape. Nature and rules have their own characteristics, and their spatial composition forms a pluralistic unity in the change of points, which does not emphasize the continuity of landscape, but pays more attention to the change of personality. Mixed layout is widely used in roof gardens.

4 Maintenance and management of roof garden

After the roof garden is completed, whether it can play its due role, we should pay attention to the growth of plants and take timely measures against unhealthy plants; Pay attention to water and fertilizer, water mainly with frequent watering and less watering, prune frequently, clean up litter in time, pay attention to drainage to prevent system blockage, and update grass flowers in time to avoid affecting the overall image.

5 Waterproof measures and load of roof garden

5. 1 Waterproof measures for roof garden

5. 1. 1 Choose good waterproof materials and adopt new thermal insulation technology to completely solve the embarrassment of "Leng Xia fever in winter" for the top floor residents, which is warm in winter and cool in summer.

5. 1.2 The use of new lightweight building materials completely avoids the danger of building quality problems caused by the increase of roof load in traditional roof garden construction.

5. 1.3 adopts new overhead technology, which completely overcomes the structural defects such as water accumulation on the top floor and root damage caused by the contact between the traditional roof garden and the roof.

5. 1.4 The new reverse osmosis filtration technology can completely overcome the soil erosion and nutrient loss of traditional roof gardens, and the soil can be cultivated once and used for a long time.

5. 1.5 new micro-spraying, drip irrigation and infiltration irrigation technologies are adopted to completely ensure the growth water demand of crops planted in the roof garden, and solve the problems of water conservation of plants and soil hardening.

5. 1.6 adopt new ecological breeding technology and optimized cultivation technology of fruits, vegetables and flowers to fully ensure the economic benefit, ornamental value and edible value of roof planting.

5. 1.7 Before the garden is built, the leakage should be checked, and the drain can be blocked on the roof. Do a good job of roof water accumulation, check whether there is water leakage, and remedy it in time.

5. 1.8 Pay attention to protect the waterproof layer during construction, and construct in strict accordance with the operation procedures. Do not damage the waterproof layer.

Swimming pool and other facilities are 5. 1.9. A separate waterproof system should be used.

5. 1. 10 Try not to accumulate water during watering. Clean up the garbage in time to prevent the sewer from clogging.

5.2 Load of Roof Garden

The loads of various garden projects in the roof garden should be converted into equivalent uniform live loads per square meter, and then compared with the loads of the garden, and accurately calculated to ensure the smooth construction of the garden.

When choosing planting substrates and plants, the weight of materials should be considered first. In addition to the original soil, new planting media can also be used. The new matrix is light in weight and has good moisture retention and water permeability.

Roof gardens are suitable for planting some low shrubs, flowers and lawns. Small trees are best planted in containers such as wooden barrels or boxes and placed on load-bearing walls or columns.

6 concluding remarks

The planning and design of the roof garden integrates the natural ecological environment of the roof with the overall ecological environment of the city, and the urban civilization lasts for a long time and is integrated with the living environment and culture. Cultivating a layer of vegetation on the roof insulation waterproof layer can expand the green area and expand the urban green lung; Second, it can provide new rest places and improve people's quality of life; Third, we can rely on roof plants to intercept some precipitation, so as to reduce the pressure and influence of high-intensity precipitation on urban flood control, irrigation and drainage systems; Fourth, it can avoid the influence of some cold winters and hot summers on the top residents. Not only that, we can also see that the roof garden is an important part of sustainable development: the garden on the ground brings convenience to people for sunshine and leisure activities, but the garden usually built on the open space is very expensive, in which land funds account for a large part. The roof garden has great advantages, but it is free in terms of land occupation. In contrast, the investment of roof garden is much less than that of garden with open space on the ground.

When people build a building, it is equivalent to destroying a piece of land. We can save the destroyed land by building the roof into a roof garden. In this way, we can not only beautify our life, but also reserve this land for future generations.

For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd