Temporary rain water collection assembly for use on a roof of a building

A rain water collection system for a blue roof system that includes a tray assembly comprising a container, a water absorbing layer located in said interior region of the container, ballast members and a cover plate. The water absorbing layer is supported on a first set of support surfaces to locate the water absorbing layer above the bottom wall of the container to provide a water collecting space into which will flow excess water that exceeds the water absorbing capacity of the water absorbing layer. The sidewalls of the container have openings therethrough to facilitate the passage of over flow water from the container and the introduction of air therethrough into the interior region. The upstanding columns have openings to facilitate the passage of air therethrough into the interior region of the container.

FIELD OF THE INVENTION

This invention relates to a rain water collection system for a blue roof system.

BACKGROUND OF THE INVENTION

Urban storm water is rain that falls over urban and suburban areas, or any place with a large percent cover of impervious surfaces such as roads, parking lots, and roofs. The management of this water is of increasing critical interest for developers, designers, and municipalities that are facing increasing ecological and political pressure to maintain pre-development site hydrology. This has been recognized in Lenhart US published patent application no. 2014/0026480 A1, published on Jan. 30, 2014.

During the 20thcentury, many of North America's major urban areas were developed with a large portion of the land area being covered by impervious surface materials such as impermeable pavements and roof membranes. This design and construction method was the standard so as to prevent water from infiltrating into and damaging infrastructure and buildings. Further, the impermeable surfaces provided a simple method for erosion control and storm water conveyance.

As these developed urban areas began to increase in population and expand into larger sub-urban areas, the amount of impermeable surfaces increased, creating a significant increase in storm water runoff. The large impermeable areas generate enormous amounts of water runoff during moderate to heavy rainfall events, far exceeding the design capacities of the existing grey conveyance systems, resulting in localized flooding, wastewater and pollution issues. Where storm water management uses only grey infrastructure, sewers transport rain or melting snow that can no longer soak into the ground, along with the pollutants the water has picked up, to the nearest body of water or to a wastewater treatment plant. Many cities have built combined sewer and storm water systems that lack the capacity to handle the increased storm water. In these circumstances, the sewer systems quite often have to release untreated sewer water into the waterways during moderate storm events. Further, recent research indicates that the percent of impervious cover in a watershed is directly related to the health of its rivers, lakes, and estuaries.

Green Infrastructure storm water management techniques generally use soil, vegetation or engineered systems to mimic natural processes to collect, cleanse and retain storm water within the watershed. Green infrastructure techniques, such as bio-retention, green and blue roof technology and underground storage in cisterns, preserve or restore the natural hydrologic cycle by infiltrating, evaporating, and harvesting rain water as close to the source as possible. These techniques use rain that falls on hard surfaces as a resource rather than treating it as a waste product. Soil, vegetation and engineered materials filter or biologically or chemically degrade many storm water pollutants that would otherwise be discharged directly into nearby water bodies by systems where only sewer pipes are used for storm water management.

In addition to reducing problems associated with grey infrastructure (sewer pipe) storm water management, green infrastructure techniques utilizing retention, storage and evaporation generally produce additional benefits, including improved air quality, mitigation of the urban heat island effect, reduced building energy costs, enhanced urban aesthetics, increased property values, and more.

Cities that have begun integrating green infrastructure into their storm water management have found it to be cost competitive with conventional storm water management, as well as more effective.

Currently, the trend for roof top green infrastructure has been to place vegetation on flat rooftops (Green Roof). The primary benefits of installing a vegetated roof are a lowering of cooling costs and energy consumption, storm water mitigation, heat reduction, and aesthetics. Although vegetated roof systems have proven to be successful on a modest scale, they are limited in their application potential. Not every roof can support the weight of a vegetated system. Further vegetated systems are limited in that an urban rooftop is a very challenging environment to grow plants. There are many challenges, such as drought, climate extremes, high winds, pollution, poor maintenance and a limited plant palate.

Accordingly, it is an object of this invention to provide a product that can provide the benefits of a vegetated roof, storm water retention pond and cool roof while being practical at the commercial level.

As further object of this invention is to provide a product that can temporarily collect and store large amounts of rainfall at the source and then slowly liberate the stored water through a combination of natural processes that will effectively eliminate storm water runoff from the vast majority of rain events and greatly reduce the impact of runoff and flooding for major storm events.

It is a still further object of this invention to provide a product that utilizes natural processes to return water vapor to the local environment while providing evaporative cooling to the local rooftop.

It is a still further object of this invention to provide a system that releases stored water that cannot be evaporated at a controlled rate providing surge relief for stressed storm water systems.

It is a still further object of this invention to provide a product that is completely scalable for flat roofs from a few square feet to millions of square feet.

It is a still further object of this invention to provide a product that is cost effective, impactful, easy to install and maintain.

It is a still further object of this invention to provide a product that protects a building's roof membrane from the sun's UV rays greatly reducing solar heat gain and extending the total life of the roof membrane.

SUMMARY OF THE INVENTION

The objects and purposes of the invention are met by providing a rain water collection system for a blue roof system which includes a tray assembly comprising a container having sidewalls, a bottom wall and an open top that defines an interior region of the container, the interior region having a plurality of upstanding columns projecting upwardly from the bottom wall, a first set of upstanding columns of the plurality of upstanding columns projecting upwardly from the bottom wall to a first elevated position within the interior region so as to promote the free movement of air and water within the interior region while upwardly facing surfaces on each of the first set of upstanding columns provides a set of coplanar first support surfaces spaced above a plane of said bottom wall, a water absorbing layer located in the interior region, the water absorbing layer being supported on the first support surfaces so that an upwardly facing surface of the water absorbing layer is exposed to the environment, the spacing of the first support surfaces above the plane of the bottom wall facilitating the provision of a water collecting space between an underside of said water absorbing layer and the bottom wall to facilitate the flow of excess water that exceeds the water absorbing capacity of the water absorbing layer into the water collecting space of the interior region that is between the underside of the water absorbing layer and the bottom wall, and the plural sidewalls of the container having plural openings therethrough to facilitate the passage of air and over flow water therethrough, the air flowing into and around the plurality of upstanding columns, the water absorbing layer, and the water collecting space to enhance the evaporation of water from the water absorbing layer and the water collecting space.

DETAILED DESCRIPTION

FIG. 1illustrated a rain water collection system20and includes a plurality of individual tray assemblies21that are interconnected to one another as will be explained in more detail below. Each tray assembly21has a container22, an absorbing layer23, ballast assemblage24and a cover plate assembly25.

The container22(FIGS. 2 and 3) is formed from a suitable thermoplastic resin based material, such as ABS, Polyethylene, Polypropylene. metal or wood and includes a bottom wall31and a plurality of upstanding sidewalls32that are integral with the bottom wall31and with each other. In this particular embodiment, the container is rectangular or square as shown in the top view ofFIG. 2and includes four upstanding sidewalls32to define an interior region33of the container22. Each of the sidewalls32are inclined to the vertical and terminate at an upper horizontally flat surface27that is oriented in a plane that is parallel to a plane containing the floor of the bottom wall31and, at an outer peripheral edge thereof, a vertically upstanding wall or rim34. The surface27also extends between the corners as shown inFIG. 2. A screw receiving hole (not shown) is provided on the surface27in each corner of the container adjacent the rim34. If desired, a slot26(FIG. 14) can be provided in the sidewalls32adjacent each corner and configured to hold in place a metal clip28with a screw receiving hole29in it that becomes aligned with the screw receiving hole in the surface27. A through rectangular hole30is provided in the surfaces27about midway of each sidewall22.

A plurality of individual upstanding and hollow columns40are provided on the bottom wall31and are integral therewith. In this particular embodiment, the individual columns40are laterally spaced from one another to allow air and water in the interior region33of the container to move freely about unobstructed by the individual columns40. While each column can be of any cross sectional shape, in this particular embodiment, each column40closest to the geometric center of the bottom wall31is generally X-shaped and terminates at an upper end in an X-shaped flat surface41that is parallel with the floor of the bottom wall31and is spaced a finite distance below the plane containing the flat surfaces27. At least one through opening42, here a plurality of through openings42are provided in the flat surface41and each thereof extends to the sidewalls43of the column40to facilitate the passage of air to and from the hollow interior of the columns40through the openings42. A lower edge44(FIG. 4) of each opening40is located a finite distance from the plane of the floor of the bottom wall31.

The columns40A and40B adjacent the four corners of the interior region33are generally L-shaped with the included angle45between the legs of the L of the columns40A facing the corners. Like the columns40, the columns40A and40B each terminate at an upper end in a flat surface41A and41B, here an L-shaped flat surface, that is parallel with the floor of the bottom wall31and is spaced a finite distance below the plane containing the surfaces27. At least one through opening42A and42B, here a plurality of through openings42A and42B are provided in the flat surface41A and41B, respectively, and each thereof extends to the sidewalls43A and43B of the column40A and40B, respectively to facilitate the passage of air to and from the hollow interior of the columns40A and40B through the openings42A and42B. A lower edge44A and44B of each opening40A and40B is located a finite distance above the plane of the floor of the bottom wall31and in a coplanar relation to the lower edges44in the columns40.

A plurality of separate pockets46are formed in the bottom wall31with each pocket having a bottom wall47that is located in a plane that is parallel to and oriented below the plane of the floor of the bottom wall31. The bottom wall47of each of the pockets46forms a support surface48on the underside thereof, which results in the underside of the bottom wall31becoming elevated above a roof surface RS (FIG. 6) upon which each container22is placed. A spacing49between the underside of the bottom wall31and the roof surface RS will facilitate the passage of air and water therethrough.

In some instances, it is desirable to line the roof surface RS (FIGS. 4 and 6) with a roof slip sheet51to isolate the roof structure from the weathering effect caused by the elements of the atmosphere. The support surfaces48each have pads52secured thereto to protect the roof surface RS from wear caused by the placement of containers22thereon as well as protect the roof slip sheet51from the aforesaid wear.

A drain opening53is provided in the bottom wall31of the container22. An upstanding flange54of a finite height above the floor of the bottom wall31encircles the drain opening53. The drain opening53provides a passageway between the interior region33and the space49between the roof surface RS and the underside of the bottom wall31.

A plurality of additional upstanding and hollow columns60are provided on the bottom wall31and integral therewith as well as being integral with selected ones of the columns40. In this particular embodiment, there are four additional columns60equidistantly spaced from each other and the drain opening53. Each additional column60is generally L-shaped in cross section with the length of the legs61of the L-shape being equal. The legs61each have upstanding sidewalls62defining an angle63therebetween which open toward the drain opening53so that the sidewalls62of each of the legs61on each of the additional columns60define a rectangle or a square area64. The sidewalls62also each have a step feature66(FIGS. 4 and 5) defining a generally horizontal support surface67that is elevated above the upper rim of the upstanding flange54encircling the drain opening53. The upstanding columns60each terminate at the upper end in a flat support surface68that is coplanar and parallel with the support surface27. Furthermore, the support surfaces68are elevated above the support surfaces41aand41B a finite distance to be coplanar, as aforesaid, with the surfaces27in each of the corners of the container22. The support surfaces68at the top of each leg61have at least one opening69providing a through passageway to the interior of the columns60.

Each additional column60is also integrally connected to the columns40that are equidistantly spaced from the drain opening53so that the columns40will form a buttress support for the columns60. A lower edge71of each opening69is elevated a finite distance above the coplanar lower edges44,44A and44B of the openings42,42A and42B, respectively, as illustrated inFIGS. 3 and 4.

Further upstanding and hollow columns60A are provided on the bottom wall31and integral therewith as well as being integral with columns40A and40B in each of the four corners of the interior region33of the container22. In this particular embodiment, there are a total of four further columns60A equidistantly spaced from each other and the drain opening53. Each further column60A is generally L-shaped in cross section with the length of the legs61A of the L-shape being equal. The legs61A each have upstanding sidewalls62A defining an angle63A therebetween which open toward the respective corner of the container22. The upstanding columns60A each terminate at the upper end in a flat support surface68A that is coplanar and parallel with the support surface27. Furthermore, the support surfaces68A are elevated above the support surfaces41,41A and41B a finite distance to be coplanar, as aforesaid, with the surfaces27in each of the corners of the container. The support surfaces60A at the top of each leg61A have at least one opening69A providing a through passageway to the interior of the columns60A. A lower edge71A of each opening69A is elevated a finite distance above the coplanar lower edges44,44A and44B of the openings42,42A and42B, respectively, as illustrated inFIGS. 3 and 4.

Each additional column60A is also integrally connected to the columns40A and40B so that the columns40A and40B, straddling the respective column60A, will form a buttress support for the further columns60A.

Each sidewall32of the container22has a plurality of laterally spaced side through openings76to provide plural passageways between the interior region33of the container and the exterior thereof through the openings76in the sidewalls32. In this particular embodiment, each of the openings76is of the same cross sectional area and has lower edges77that are oriented in a plane that is parallel to and below the plane containing the flat surfaces27. Furthermore, the lower edge77of each opening76is coplanar with the lower edges44,44A and44B of each of the openings42,42A and42B in the columns40,40A and40B. There is also a through opening76A located in each corner of the container22as shown inFIG. 3. The lower edge of these openings is elevated above the lower edges of the openings77,44,44A and44B as shown inFIGS. 3 and 14.

Side-by-side containers22as shown inFIG. 1are held together by an inverted U-shaped clip mechanism81as shown inFIG. 7. The U-shaped clip is made of a spring metal and includes two legs82interconnected by a bight section83. The lateral spacing between the distal ends84of the legs82is less than the lateral spacing of the adjacent openings30in the surfaces27of the container22to that the legs82will require a force to spread the legs82apart so that the distal ends84become aligned with the openings30and facilitate the insert of the legs82through the openings30and enable the bight section83to engage the upper edge of the rim34, A release of the force spreading the legs82apart will cause the distal ends84to spring together to thereby hold the containers22in the side-by-side relation and prevent the containers from separating.

The ballast assemblage24includes at least one ballast block85and is provided to add weight to the containers22. In this particular embodiment, the ballast assemblage includes plural individual ballast blocks86stacked one upon the other in the rectangular or square area64and lodged into the angles63defined by the legs62of each of the columns60. Shown inFIG. 5, the stack of ballast blocks86rest on the support surfaces67at the base of the columns60to locate the bottom surface of the lowermost ballast block86slightly above the upper edge of the rim54encircling the drain opening53.

FIG. 8illustrates an isometric view of a first embodiment of the absorbing layer23as viewed from the top and two edges. In this particular embodiment, the absorbing layer23is rectangular or square and thus appears the same at the four edges. The absorbing layer23includes a top layer91of uniform thickness corresponding in thickness to a dimension approximately equal to the vertical spacing that exists between the coplanar flat surfaces41,41A and41B at the upper ends of the columns40,40A and40B, respectively and the surfaces27just inside the rim34of the container22as shown inFIG. 5.

A centrally located opening93provided in the top layer91and the opening is located directly above the central region64of the container22and is of the same size or slightly larger than the size of the central region64in the container22and preferably slightly larger than the ballast blocks86so that the ballast blocks will be accessible through the opening93. The opening93also expands into four L-shaped cutout openings94that are contiguous with the central opening93so as to facilitate the upper ends of the columns60to be received therethrough to locate the upper flat surfaces68thereon in approximately the same plane as the upper surface of the top layer91of the absorbing layer23as shown inFIG. 5.

The underside of the top layer91is, as shown inFIG. 9, provided with a plurality of individual columns96integral with the top layer91and each of which extend from the underside of the top layer91downwardly and into a respective pocket46provided in the bottom wall31of the container22and rest on the bottom wall47of the pockets46as shown inFIG. 6. Each of the columns96is rectangular or square in cross section and are, in this particular embodiment, equal in cross sectional area with the possible exception of the corner columns96A and the columns96B surrounding the central opening93of the absorbing layer23and are equidistantly spaced from the drain opening52. The columns96A and96B each have a beveled corner to accommodate the beveled corners of the container22and the individual ballast blocks86located in the central region64of the container22.

An additional four L-shaped cutouts98are provide in the top layer91as shown inFIG. 8. The aforesaid cutouts98facilitate the reception thereon of the L-shaped upper ends of the columns60A to locate the upper flat upper surfaces68A thereon in a plane which is approximately the same as the plane of the upper surface of the top layer91. The absorbing layer23has a plurality of through holes97A and97B therein, the holes97A extending through the top layer91and the holes97B extending through both the top layer91and each column96A and96B.

The absorbing layer23is of a unitary construction and is made of a natural cellulose sponge sheet that is trimmed to the configuration shown inFIGS. 8 and 9.

The cover plate25illustrated inFIGS. 1, 10 and 11is sized to fit wholly within the rim structure34at the top of the container sidewalls31of the container22and all four edges of the cover plate25rest on the surfaces27that are located adjacent the four sides of the rim structure34. The cover plate25has a central flat plate area102with spoke-like ribs103extending radially outwardly of the central plate area102to each corner104of the plate255. The distal ends of the spoke-like ribs103are interconnected at the corners104and by an edge member106that extends between the corners104. The plural edge members106rest on the surfaces27of the container22and each thereof has a notch107located mid-length thereof. Other rib members108are located between the edge members106and the central plate area102and these other rib members108are each connected at their opposite ends to a respective spoke-like rib103and extend parallel to each other and to the edge members106. The horizontal spacing between the edge members106, and the next adjacent rib members108is maintained by reinforcing members109that are connected to and extend between the mid-length segments of thereof and as shown inFIG. 11. Each of the members106and108define a generally planar upwardly facing surface. It is preferable for the edge members106and the other rib members108to have a generally inverted U-shaped or an L-shaped cross section to reinforce the strength of the members and prevent a bending thereof out of the plane of the aforesaid upwardly facing surface when a person should walk thereon. However, it also be noted that the upwardly facing surface of each of the members106and108is inclined to the horizon as shown at111inFIGS. 7 and 14to define rain water deflection surfaces.

A through hole112is provided in each corner104of the cover plate25and the locations thereof are designed to align with the holes19on the container22. Screws113are received in the holes112and are configured to fasten to a respective metal clip28on the container22to effect a connection of the cover plate25to the top of the container22. When in this condition, the underside of the cover plate25will rest on and be supported by the surfaces27and the upper surfaces68and68A of the columns60and60A, respectively. This support and the reinforced strength provided by the construction of the cover plate will facilitate a person walking on the cover plates of multiple tray assemblies21.

In some situations, and to reduce the expense of making the absorbing layer23, it may be desirable to use a modified absorbing layer, such as the absorbing layer23A illustrated inFIG. 12, namely, an absorbing layer23A without columns protruding downwardly from the underside of the layer. In this particular embodiment, the absorbing layer would be identical to the construction of the top layer91inFIG. 8and accordingly, the same reference numbers used in describingFIG. 8above have been used but with the prefix “1” having been added thereto. Since the absorbing layer23A does not have columns, the holes197A and197B are all identical to each other. Thus, a further description of this embodiment is deemed unnecessary.

In some still further situations, it may be desirable to use a further modified absorbing layer, such as the absorbing layer23B is illustrated inFIG. 13, namely, a two part absorbing layer comprised of the top layer191identical to the top layer91illustrated inFIG. 12and separate individual columns120. The columns120each have a top to bottom extending hole121therethrough. The individual columns120are configured to be received in the pockets46in the bottom wall32of the container22and the top layer191rests on the top surfaces41,41A,41B and the tops of the columns120. The holes197A in the top layer191are configured to be aligned with the holes121in the columns120when the absorbing layer23B is assembled into the container22.

A plastic or other suitable material wind deflector130(FIG. 15) is configured to attach to the outside perimeter of a tray assembly21so as to prevent high winds from penetrating under the containers22bottom side creating undesirable wind lift between the containers and the roof surface RS. In this particular embodiment, the wind deflector130has a generally 1-shape having a horizontal leg131that extends between the peripherally situated protective pads52and the slip sheet51lining the roof surface RS until the upstanding wall132on the upper side of the leg131engages the sidewall32of the container22. The wind deflector130also has a generally vertically inclined leg133integral with the horizontal leg131which terminates at an upper edge134that conforms in shape to the peripheral edge of the cover plate25. An outwardly opening notch136is provided adjacent the upper edge134. The wind deflector is configured to connect to the container22adjacent to the upper edge thereof and the upper edge of the rim34and an opening30(FIGS. 2 and 3) so as to accommodate the insertion of one leg of a spring clip81through the opening30while the distal end84the other leg of the spring clip81is received in the notch136to hold the clip in place. If desired, the wind deflector may also be secured to the upper edge of the sidewall32by one or more screws (not shown).

Operation

While the operation of the rain water collection system20will be understood by those skilled in the art, the below set forth description of the operation is being provided only for convenience in understanding.

When the components described above have been assembled to create our rain water collection system20as illustrated inFIGS. 6 and 14, for example, rain water will enter the tray assembly21through the cover plate25and the spacing provided between the members106and108thereon. Rain landing on the members106and108will be directed to the top of the absorbing layer23by the inclined surfaces at111. The rain water will be absorbed by the absorbing layer23. Assuming that the amount of rain water collected in the absorbing layer23from a rain storm does not exceed the water retention capacity thereof, dry air will move into the internal region33of the container22, through the holes97A and97B in the absorbing layer as well as throughout the container22to facilitate evaporation of water from the absorbing layer and eventually dry it without any rain water having left the container via the drain opening53.

If, on the other hand, the amount of rain water to enter the tray assembly21exceeds the water retention capacity of the absorbing layer23, excess water will enter the interior region33of the container located immediately below the top layer91of the absorbing layer23. If the amount of the excess water is enough to fill the container22to a level above the upper rim of the flange54surrounding the drain opening53, this water will exit the container via the drain opening and water will flow eventually to the roof drains on the building roof. The size of the drain opening53will determine the rate at which this water will exit the container22. Once the level of the water in the container22is lowered to the level of the upper rim of the flange surrounding the drain opening, water will have previously soaked into the columns96and96A and be wicked upwardly into the top layer91of the absorbing layer23. Thus, the term “wicking columns” will be used to refer to the columns96and96A. After the rain storm has ended, dry air will enter the container through the cover plate25and the openings76and76A and move about the periphery of the absorbing layer23, particularly the top layer91and the wicking columns96and96A, to facilitate the evaporation of water therefrom. Water soaked into the wicking columns will continue to be wicked up into the top layer91and this process will continue until all wetness in the absorbing layer23has dried. In this situation, only a minimal amount of rain water will have exited the container22through the drain opening53.

If, on the other hand, a torrential amount of rain water is permitted to enter the container22to saturate the absorbing layer23, the excess rain water will exit the absorbing layer23to enter the interior region33of the container22directly below the top layer91of the absorbing layer23. The lower edge of the openings41,41A,41B and77will facilitate the overflow of water from the container22onto the roof surface of the building. Oftentimes, the delay in rain water runoff exiting a building roof will provide sufficient time for the local storm water management systems to receive the roof runoff water without resulting in localized flooding conditions.

Although particular preferred embodiments of the invention have been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus lie within the scope of the present invention.