Roof-greening cassette

Abstract

A roof-greening cassette, at least partially or predominantly having walls and/or bases made of (porous) material having pores, the porous material having the following properties: (a) a water absorption of 15 to 30 liters/m.sup.2 in the case of a material thickness of 30 mm, and (b) a water permeability normal to the plane of 8 to 16 liters/(m.sup.2 s), in the case of a water column of 200 mm and a material thickness of 30 mm.

Claims

1. A roof-greening cassette, having walls and bases, wherein at least one of the walls and the bases is made of a porous material having open pores, wherein the porous material has the following properties: a) a material thickness of 30 mm; b) a water absorption of 15 to 30 liters/m.sup.2; c) a water permeability normal to the plane of 8 to 16 liters/(m.sup.2 s) based on a water column of 200 mm: and d) is made of polyurethane.

2. The roof-greening cassette according to claim 1, wherein the porous material has an air permeability of 133.3 liters/(m.sup.2s) at a test pressure and/or difference in pressure of 200 Pa.

3. The roof-greening cassette according to claim 1, wherein the porous material has a tensile strength of at least 100 kPa.

4. The roof-greening cassette according to claim 1, wherein the porous material has an elongation at break of at least 60%.

5. The roof-greening cassette according to claim 1, wherein at least the bases consist of the porous material.

6. The roof-greening cassette according to claim 1, wherein the walls and the bases consist of the porous material.

7. The roof-greening cassette according to claim 1, wherein the porous material is elastic, open-celled and inhomogeneous and has zones of different hardnesses.

8. The roof-greening cassette according to claim 1, further comprising at least one open-top compartment formed by the walls and the bases, the at least one open-top compartment having a filling of inorganic substances.

9. The roof-greening cassette according to claim 8, wherein the inorganic substances have a particle size of 0.5 mm to 10 mm.

10. The roof-greening cassette according to claim 1, wherein the cassette has zones of different densities.

11. The roof-greening cassette according to claim 1, further comprising underside grooves.

12. The roof-greening cassette according to claim 11, further comprising at least one open-top compartment formed by the walls and the bases, wherein the underside grooves extend at least in one direction centrally beneath the at least one open-top compartment.

13. The roof-greening cassette according to claim 11, further comprising upper side walls extending from the bases, wherein the underside grooves extend at least in one direction centrally beneath the beneath upper side walls.

14. The roof-greening cassette according to claim 11, further comprising at least one open-top compartment formed by the walls and the bases and upper side walls extending from the bases, wherein the underside grooves extend at least in one direction centrally beneath the at least one open-top compartment and beneath the upper side walls.

15. The roof-greening cassette according to claim 1, wherein the porous material has an air permeability of 183.3 to 250 liters/(m.sup.2s) at a test pressure and/or difference in pressure of 200 Pa.

16. The roof-greening cassette according to claim 1, wherein the porous material has 600 to 900 cells per cm.sup.2.

17. The roof-greening cassette according to claim 1, wherein the porous material has a tensile strength of 120 to 140 kPa.

18. The roof-greening cassette according to claim 1, wherein the porous material has an elongation at break of 70 to 85%.

19. The roof-greening cassette according to claim 1, wherein the porous material has a compressive strength of at least 20 kPa.

20. The roof-greening cassette according to claim 1, wherein the porous material has a compressive strength of 24-28 kPa.

21. The roof-greening cassette according to claim 1, wherein the porous material contains carbon black for UV-stabilization purposes.

22. The roof-greening cassette according to claim 1, wherein the porous material is elastic, open-celled and inhomogeneous and has zones of different densities.

23. The roof-greening cassette according to claim 1, wherein the porous material is elastic, open-celled and inhomogeneous and has zones of different hardnesses and densities.

24. The roof-greening cassette according to claim 1, wherein the walls and the bases do not have any through-passages, openings, slots or apertures.

25. The roof-greening cassette according to claim 1, wherein the bases have a lower density than the walls.

26. The roof-greening cassette according to claim 1, wherein the porous material is selected from the group consisting of: a) polyurethane flakes; b) polyurethane flakes having a common density; c) a mixture of polyurethane flakes having different densities; and d) polyurethane flakes having a density of 80 kg/m.sup.3.

27. A roof comprising a roof-greening cassette resting thereon, wherein the roof-greening cassette has walls and bases, wherein at least one of the walls and the bases is made of a porous material having open pores, wherein the porous material has the following properties: a) a material thickness of 30 mm; b) a water absorption of 15 to 30 liters/m.sup.2; c) a water permeability normal to the plane of 8 to 16 liters/(m.sup.2 s) based on a water column of 200 mm: and d) is made of polyurethane.

28. The roof according to claim 27, wherein the porous material is selected from the group consisting of: a) polyurethane flakes; b) polyurethane flakes having a common density; c) a mixture of polyurethane flakes having different densities; and d) polyurethane flakes having a density of 80 kg/m.sup.3.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Advantageous embodiments of the invention will be explained in more detail hereinbelow with reference to drawings, in which:

(2) FIG. 1 shows a plan view of a roof-greening cassette,

(3) FIG. 2 shows a view of the roof-greening cassette from beneath,

(4) FIG. 3 shows a longitudinal section of the roof-greening cassette,

(5) FIG. 4 shows a cross section of the roof-greening cassette,

(6) FIG. 5 shows a perspective illustration of the roof-greening cassette as seen obliquely from above, and

(7) FIG. 6 shows an enlarged illustration of a cut surface.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(8) A roof-greening cassette 10 is of cuboidal design and has, one beside the other and one behind the other, a plurality of cuboidal, open-top compartments 11, in this case seven compartments in the longitudinal direction of the cassette and three compartments in the transverse direction of the cassette, each separated by side walls, that is to say longitudinal walls 12 and transverse walls 13. Outer transverse walls are referred to as end walls 14, and outer longitudinal walls are referred to as longitudinal side walls 15.

(9) The cassette 10 has preferably outer dimensions of approximately 100 cm (length)60 cm (width)5 cm (height). The cassettes are formed from strips or panels made of selected PUR flakes with a density of approximately 80 kg/m.sup.3. Depending on numbers, it is also possible for the cassettes to be produced in one piece, for example by molding or pressing. The cassette is preferably produced by virtue of the flakes being compressed in a mold, in particular in conjunction with the mold and/or the flakes being heated.

(10) On its underside, the cassette 10 is designed to be planar, but with a grid of transversely and longitudinally running grooves 16, 17, see base wall 18 in FIG. 2. The size of the grid formed in this way corresponds to the size of the grid made of longitudinal walls 12 and transverse walls 13. However, the transverse grooves 17 are arranged in an offset manner, that is to say approximately centrally between the transverse walls 13. According to FIG. 2, the longitudinal grooves 16 are located directly beneath the longitudinal walls 12. Here too, however, offsetting is possible, as is an arrangement of the transverse grooves 17 directly beneath the transverse walls 13.

(11) Each compartment 11 has a dedicated base. The bases of the compartments 11, together, form the base wall 18. The bases and walls each have a thickness of approximately 1 cm.

(12) The grooves 16, 17 can perform in particular two functions. On the one hand, the grooves allow drainage. Waterlogging is avoided. On the other hand, individual grooves can be used for accommodating reinforcing profiles. This allows shearing forces occurring on pitched roofs to be absorbed to better effect.

(13) The compartments 11 of the cassettes are filled with substrate 19 preferably at ground level. The substrate is, in particular, soil with seeds or shoots, and possibly fertilizer, suitable for cultivating the roof greenery. A greening system with sedum is preferred. Once filled, the cassettes are positioned, and fixed, on the roof which is to be greened. Cultivation up to the point of visible plants being developed can be carried out at ground level or on the roof. It is preferable for cultivation to be carried out entirely at ground level. Better monitoring of the watering is possible in this case. The watering can take place at relatively large time intervals, for example for a first time in conjunction with the operation of filling the compartments with substrate and thereafter only after a certain time interval.

(14) Using the material of the aforementioned type renders the walls of the cassettesincluding the base wall 18capable of accommodating root penetration and water-retentive. Depending on the material used, it is also possible to have a long service life, corresponding to the projected service life of the roof.

(15) The preferably greened cassettes 10 are laid out one beside the other and one behind the other, without gaps, on a roof (not shown). The residual surfaces which are left on the roof as a result of the unit dimensions can have sub-cassettes laid on them. These sub-cassettes can be easily produced by virtue of individual cassettes 10 being divided and separated.

(16) The individual walls 12 to 15 have a thickness of approximately 1 cm. On account of the necessary load-bearing capability, the base wall 18 is of somewhat thicker design, with a thickness of approximately 3 cm, minus the grooves 16, 17, of 1 cm in depth and width, which are provided in some regions. The grooves 16, 17 are also provided all the way around the periphery, that is to say beneath the end walls 14 and longitudinal side walls 15.

(17) FIG. 5 shows a cassette 10 filled partially with substrate 19. In practice, all the compartments 11 are filled with substrate.

(18) FIG. 6 shows a cut surface of the porous material of the cassettes, measuring approximately 2 cm2 cm. It is possible to see regions 20, 21 of different densities on account of an inhomogeneous raw material having been compressed. Said material consists, for example, of selected flakes/fibers of different densities and sizes. Some pores or cells, or transitions between the pores or cells, are visible.

LIST OF DESIGNATIONS

(19) 10 Roof-greening cassette

(20) 11 Compartments

(21) 12 Longitudinal walls

(22) 13 Transverse walls

(23) 14 End walls

(24) 15 Longitudinal side walls

(25) 16 Longitudinal grooves

(26) 17 Transverse grooves

(27) 18 Base wall

(28) 19 Substrate

(29) 20 Region

(30) 21 Region