To help prevent or reduce the speed of global warming, adding a green open space with a garden on the roof of houses, buildings, hotels and offices is one effective way. Although the condition of the urban region largely filled by a high rise building, the designers (architects, and landscape architect) must create a green open space to add plants that have been taken over when the building was constructed.
By creating a garden on the roof, high-rise buildings can still have a green open space, because there is space efficiency. Park on the roof (roof garden) is as an alternative reforestation to improve the quality of big city environmental health. Currently, only some five-star hotel in central Jakarta which has a garden on the roof (roof garden).
Making a garden on the roof (roof garden) is not cheap and need structure and specific roof construction. Even for optimal results, the construction of the roof to the garden was designed from the beginning, before the building was constructed. However, this investment can come back in a few years later, because the cost of electricity is reduced air conditioning, and building economic value added.
A private hospital in Singapore succeeded in reducing electricity consumption by 50 percent, after making a garden on the roof (roof garden). Although the roof garden is just a tomato plant, which is placed in the pot to cover the entire roof. Another advantage, the hospital did not have to buy tomatoes anymore.
In addition to the shade, the garden on the roof (roof garden) can also be used to absorb toxic gases. For example, bamboo or palm can absorb formaldehyde gas and gasoline. While the lily plant, in addition to absorb formaldehyde gas and gasoline, alcohol and acetone also absorb the resulting paint and so forth. Vines also serves to absorb gases acetate, ammonia, and other gases. Because of this function, the vines have been used to park on the roof (roof garden) outside the country such as Singapore and Japan.
How to Build a High-Roof Garden
Before making a rooftop garden, first consider the construction of the roof of the building. Is it designed to support the burden of growing media in the form of land and trees will be planted on it or not. Because the garden on the roof (roof garden) should be supported structure and strong roof construction.
The existence of a garden on the roof (roof garden) will lead to increasing burden. Heap of soil and plants will add dead load, wind load, and additional water load on the roof of the building. The building must have a drainage system that works well.
If the type of plant shrubs to be planted, he take into account the roof load will increase about 650 kg/m2. In addition to live load according to activity on the roof garden. For example, 400 kg/m2 for sports, 500 kg/m2 to party and dance, and 250 kg/m2 for restaurants.
To plant a large tree, the location must be supported slab to slab concrete structural columns do not collapse. In addition, the retaining wall needs to be made because the trees require adequate soil thickness, or make a hole in the roof of the building, under a tree.
Construction roof leak-prone, so it must be equipped with drainage channels. Drainage layer such as gravel, sand, and pumice stones should be added for easy water flow into the drain hole. Filters are made of geo textiles or fibers functioning drain water down but retains soil so as not to clog the sinkhole.
To prevent damage to water-resistant coating (water proof layer), barrier layer must be added to the plant roots do not damage the waterproof coating and the concrete underneath.
Because the plants on the roof exposed to direct sunlight and the wind faster, watering should be done regularly. So we need water spraying can be done manually or automatically.
For the planting medium, the formula should be light but has the ability to provide nutrients and moisture. For example, by mixing sand with wood shavings plus a layer of pine bark and manure. The depth of planting medium for grass requires 20 to 30 centimeters, as well as cover crops. Meanwhile, shrubs and small trees require a depth of 60-105 centimeters. A large tree to a depth of nearly 2 meters.