Rooftop greening device

Abstract

To provide a rooftop greening device that can temporarily retain a large quantity of rainwater from short, intense rainfall, while enabling weight reduction.SOLUTION: A rooftop greening device comprises: a water-permeable elevating material 4 laid on a rooftop surface of a building; cylindrical bodies 5 arranged on an upper surface of the elevating material 4; a water-retaining material 6 accommodated in the cylindrical bodies 5, the water-retaining material being capable of absorbing and retaining water from its surface and draining water from the surface; a filter 8 laid on the cylindrical bodies 5; and soil covering an upper surface of the filter 8.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a rooftop greening device for greening the rooftops of buildings.

Background Art

[0002] In recent years, rooftop greening technologies have been developed for purposes such as heat countermeasures and heat island phenomenon countermeasures, and attempts have been made to green the rooftops of many buildings.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, due to concentrated heavy rain that causes heavy rain in a short time in urban areas due to the influence of recent climate change, a large amount of rainwater flows into the sewer, and damage such as water flowing back from the sewer to the ground has become apparent.

[0005] However, if rooftop greening is to be carried out over a large area on the rooftop, a large amount of soil will be spread, and a large heavy object will be installed on the rooftop of the building. Therefore, problems such as an increase in countermeasure costs, such as providing a load-bearing structure for the building, occur.

[0006] Also, if part of the soil is replaced with styrofoam in order to reduce weight, while weight reduction is possible, there is a problem that the styrofoam floats up due to rainwater.

Means for Solving the Problems

[0007] Therefore, as a means for solving the above problems, the rooftop greening device according to the present invention includes a water-permeable raising material laid on the rooftop of a building, water-permeable cylinders arranged on the upper surface of the raising material, a water retention material housed in the cylinders, capable of absorbing water from the surface and retaining water, and draining water from the surface, a filter laid on the cylinders to inhibit the entry of roots, and soil covering the upper surface of the filter. Here, a water retention unit for a rooftop greening device can be formed by a water-permeable cylinder and a water retention material housed in the cylinder, capable of absorbing water from the surface and retaining water, and draining water from the surface.

[0008] Also, it is preferable that the peripheral surface of the cylinder is formed in a bellows shape. This is because by forming it in a bellows shape, the load-bearing strength of the cylinder against the weight of the soil can be improved, and deformation over time can be prevented. Also, the water retention material is a material that can temporarily absorb and retain water, and can discharge the absorbed water over a certain period of time.

[0009] As a preferable example of the water retention material, a gel, a fiber compression body, a woven fabric, or a porous foam molded body can be used. As a specific example of the fiber compression body, felt or a non-woven fabric can be used. As a specific example of the woven fabric, a cotton woven fabric, a chemical fiber woven fabric, or the like that can temporarily retain water can be used. Also, as a specific example of the porous foam molded body, a sponge can be used. If a sponge is used as the water retention material, the weight of the rooftop greening device can be reduced compared to the case of using soil.

[0010] If a porous foam molded body is used, the outer shape of the water retention material can be maintained without shrinking even during drying, so that the state in which the porous foam molded body is inserted in a state of being in pressure contact with the inner surface of the cylindrical body can be maintained. Therefore, if it is a water retention material which is a porous foam molded body, it is possible to prevent the water retention material from detaching from the cylindrical body due to repeated water absorption and drainage. Also, if it is a sponge, it can temporarily retain rainwater and can drain it gradually over time. Furthermore, if it is a sponge, the apparent volume does not change even during drying, so it is possible to prevent displacement due to unexpected displacement within the cylinder.

[0011] In addition, it is preferable that the filter not only has a function of preventing the intrusion of roots, but also constitutes a water permeable filter having a storage part capable of storing a part of the water that has penetrated through the soil and permeating the other part of the water. At this time, the filter having a function of preventing the entry of roots and the water permeable filter may be integrally formed, or may be formed by combining different structures. In the case of a combination of different structures, it is preferable to use a fabric or a non-woven fabric for the filter having a function of preventing the entry of roots. For the water permeable filter, a resin-molded plate-like body formed with a concave storage part may be used.

[0012] Furthermore, among the plurality of arranged cylindrical bodies, it is preferable that at least the upper surface of the cylindrical body at the end is formed as a flat surface. By forming the upper surface of the cylindrical body in a shape having a flat surface, even when the filter is made of a soft material, the edge of the filter can be supported by the flat surface, thereby preventing it from hanging downwards. By preventing the edge of the filter from hanging down, it is possible to prevent the soil filled thereon from falling onto the rooftop.

Effects of the Invention

[0013] According to the present invention, rainwater that has fallen on the rooftop of a building can be temporarily retained in a cylindrical body in which a water retention material is accommodated, and then gradually drained, thereby preventing a large amount of rainwater from flowing out from the building to the sewer due to heavy rain.

[0014] Furthermore, by arranging the cylindrical bodies on the upper surface of the elevation material, the water discharged from the water retention material flows under the elevation material, thereby preventing the drainage from the rooftop greening device to the outside of the building due to one water retention material reabsorbing the water from other water retention materials that are adjacent to each other.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

[0017] 〔Embodiment 1〕 Figure 2 is a cross-sectional structure showing the outline of the rooftop greening device 1 according to Embodiment 1. The rooftop greening device 1 has a water-permeable raising material 4 laid on the rooftop surface 3 of the building 2 and cylindrical bodies 5 arranged on the upper surface of the raising material 4. Here, as shown in Figure 1, in Embodiment 1, a water retention material 6 composed of a sponge is accommodated inside the cylindrical body 5 to form a water retention unit 7. A filter 8 is laid on the cylindrical body 5, and the upper surface of the filter 8 is covered with soil 9. Suitable plants 10 for rooftop greening are planted in the soil 9. Note that a large number of water permeable holes 5a are formed on the peripheral surface of the cylindrical body 5, allowing water to pass through the inside of the cylindrical body 5, and the water that has penetrated the soil 9 and reached the water retention unit 7 can be efficiently absorbed by the water retention material 61. Also, a connecting portion 5b is provided at one end of the cylindrical body 5, and by connecting a plurality of cylindrical bodies 5, the length of the water retention unit 7 can be adjusted according to the size of the rooftop surface 3.

[0018] A filter 8 that stops the soil 9 and has water permeability is used. Furthermore, a filter made of a soft material can be used. In Embodiment 1, a sheet-shaped filter 81 composed of a non-woven fabric is laid on the upper surface of the cylindrical body 5. The filter 81 allows water to pass through while stopping the passage of the roots of the growing and extending plants 10. By laying the filter 8, it is possible to prevent the roots of the plants 10 that have grown through the soil 9 from reaching the cylindrical body 5 and getting entangled, etc., which would inhibit the water retention effect of the water retention material 6.

[0019] In Embodiment 1, cylindrical cylindrical bodies 5 are used side by side. Since the cylindrical body 5 is cylindrical, the weight of the heavy soil 9 can be dispersed and supported against the entire cylindrical body 5, preventing the structure of the rooftop greening device 1 from being damaged. Also, by withstanding the weight of the soil 9 and maintaining the shape of the cylindrical body 5, the water retention function of the water retention material 6 accommodated inside is not impaired. Furthermore, since the peripheral wall of the cylindrical body 5 has a bellows-like uneven structure, it can withstand the pressing force from the soil 9 more strongly. Also, if a resin-made cylindrical body 5 is used, the corrosion resistance against moisture can be improved.

[0020] The raising member 4 preferably has a plate-shaped support 4a and legs 4b provided on the lower surface of the plate-shaped support 4a in order to evenly support a large number of arranged cylinders 5. The plate-shaped support 4a has water permeability that allows the water discharged from the water retention unit 7 to pass through. The water permeability of the plate-shaped support 4a may be such that the material itself has a water permeation function, and more preferably, it is preferably provided with through holes or slits. The legs 4b are installed with a gap therebetween. By the legs 4b, a drainage space 13 is formed between the roof surface 3 and the plate-shaped support 4a, through which water can flow on the roof surface 3. The drainage space 13 can allow water to flow without returning it to the water retention unit 7. Therefore, the drainage space 13 is preferably formed as a series of spaces communicating along the roof surface 3.

[0021] The rainwater temporarily retained by the water retention material 6 can seep out into the drainage space 13, flow through the lower side of the plate-shaped support 4a, and reach the drainage groove 11 leading from the roof to the outside of the building.

[0022] The water retention unit 7 is arranged on the upper surface of the raising member 4, and the water discharged from the water retention material 6 flows under the raising member 4, so that one water retention material 6 will not reabsorb the water from another water retention material 6 that joins it. Therefore, it is possible to prevent the drainage from the rooftop greening device 1 to the outside of the building from being obstructed by the water retention units 7. Note that a lid 12 having a drainage hole 12a is installed at the upper end opening of the drainage groove 11.

[0023] 〔Embodiment 2〕 As Embodiment 2, among the plurality of water retention units 7 arranged on the upper surface of the bulking material 4, it is preferable that the cylindrical body 51 of the water retention unit 71 located at the end has a square cross-sectional shape as shown in FIG. 3. In the present embodiment, the water retention unit 71 is arranged so as to be in contact with the wall surface 2a. Thereby, the upper surface of the cylindrical body 51 is composed of a flat surface. Since the cylindrical body 51 of the water retention unit 71 is formed in a square shape, even when the filter 8 is made of a soft material, the edge of the filter 8 is supported by the flat surface, so that it can be prevented from hanging downward. By preventing the edge of the filter 8 from hanging downward, it is possible to prevent the soil 9 filled thereon from falling onto the roof surface 3.

[0024] Note that it is also preferable that the sponge constituting the water retention material 61 is housed with a square cross-sectional shape in accordance with the shape of the square cylindrical body 51. Further, by forming water permeable holes 51a also on the peripheral surface of the cylindrical body 51, water can be efficiently absorbed by the water retention material 61. Further, by providing a connecting portion 51b also on the cylindrical body 51, a plurality of water retention units 71 can be connected. Thereby, the length of the water retention unit 71 can be adjusted according to the width of the roof surface 3.

[0025] 〔Embodiment 3〕 As Embodiment 3, as shown in FIG. 4, it is also preferable to provide a resin substrate-type filter 82 having a recess 82b capable of storing water on the upper surface of the cylindrical body 5, and to stack and install a filter 81 made of a non-woven fabric on the substrate-type filter 82. The filter 81 is formed in a sheet shape made of a soft material having water permeability, similarly to the filter 8 according to the previous embodiment. As a preferable example of the filter 81, it is preferably formed of a non-woven fabric.

[0026] The substrate-type filter 82 is a plate-shaped body having resin-molded irregularities, and is provided with small holes 82a that exhibit a water-permeable function in a part thereof. Further, in the concave portion 82b of the substrate-type filter 82, a part of the water that has penetrated through the soil 9 can be stored. The water stored in the concave portion 82b can be returned to the soil 9 and utilized as moisture for the roots of the plant 10 to absorb. Also, the substrate-type filter 82 can prevent the roots of the plant 10 from entering the space where the water retention unit 7 is installed, similar to the filter 81.

Explanation of Signs

[0027] 1 Roof greening device 2 Building 3 Roof surface 4 Raised material 5 Cylindrical body 6 Water retention material 7 Water retention unit 8 Filter 9 Soil

Claims

1. A water-permeable raising material laid on the rooftop of a building, water-permeable cylinders arranged on the upper surface of the raising material, a water retention material accommodated in the cylinder, capable of absorbing water from the surface and retaining water, and also capable of draining water from the surface, a filter laid on the cylinder to inhibit the entry of roots, and soil covering the upper surface of the filter. The rooftop greening device is characterized by the above.

2. The rooftop greening device according to Claim 1, wherein the water retention material is made of a fiber compression body, a woven fabric, or a porous foam molded body.

3. The rooftop greening device according to Claim 1, wherein the filter constitutes a water-permeable filter having a storage part capable of storing a part of the water that has penetrated through the soil and permeating the other part of the water.

4. The rooftop greening device according to Claim 1, wherein a flat surface is formed on the upper surface of at least the end cylinders among the plurality of arranged cylinders.

5. The rooftop greening device according to Claim 1, wherein the peripheral surface of the cylinder is formed in a bellows shape.

6. A water retention unit for a rooftop greening device, which is composed of a water-permeable cylinder and a water retention material accommodated in the cylinder, capable of absorbing water from the surface and retaining water, and also capable of draining water from the surface. The water retention unit is characterized by the above.

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