Abstract:
A fungus strip that release ions when precipitation flows down on the strip that are deleterious to fungus and algae. The strip is positioned on a building material. The strip has a length, width and thickness. The ions are preferably of zinc or tin. The building material can be asphaltic roofing shingles, non-asphaltic roofing, or siding.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates to strips capable of reducing discoloration and deterioration in roof shingles. More particularly, the invention relates to strips comprising copper, tin or zinc attached to a building material such as roofing or adjacent to vents to reduce or eliminate the growth of algae and fungi.  
         [0003]     2. Reported Developments  
         [0004]     Roofing granules are extensively used in roll roofing and asphalt shingle compositions. The roofing granules are embedded in the asphalt coating on the surface of the asphalt-impregnated base material, the granules thus forming a coating that provides an adherent, weather-resistant exterior roofing surface.  
         [0005]     While the problem exists in many climates, in warm and humid climates discoloration and deterioration of asphalt roofing compositions by the growth of algae, fungi and other biological growth is of particular concern. Roofing materials, such as shingles, frequently comprise a fiberglass substrate with a filled asphalt coating. The filler in the asphalt coating acts to make the roofing materials more fire resistant; but it has also been partly responsible for the increase in microbial growth-induced staining.  
         [0006]     An organism responsible for the microbial growth-induced staining of roofing materials is a cyanobacterium, known as blue-green algae. Other bacterium species are also known to cause discoloration primarily by secreting a mucilaginous biofilm around their cells.  
         [0007]     This condition can also arise with other building materials such as Modified Bitumen APP Membranes, Modified Bitumen SBS Membranes, TPO, PVC and EPDM membranes, vinyl, fiber cement, wood and other siding materials.  
         [0008]     To prevent such discoloration the prior art proposed the use of metallic algaecides and fungicides incorporated into roofing granules that are effective in retarding the biological growth of algae and fungi. The biological growth-preventive compounds include: metallic chips, such as copper, lead, zinc, and iron; zinc-containing compounds such as ZnO and ZnS; cuprous oxide and cuprous bromide; zinc, copper, nickel and mixtures thereof; bromate; and cuprous oxide and zinc sulfide. The metallic algaecides and fungicides are deleterious to algae and fungi thereby curtailing their growth on roof shingles and other building materials and preventing discoloration.  
         [0009]     The above referred-to compositions incorporated in roofing granules are essentially designed for new roof coverings made by manufacturers of roof shingles. Alternatively, a cleaning procedure may be used which comprises a gentle application of dilute chlorine bleach and trisodium phosphate to avoid roof damage and discoloration. Roof material cleaning by gentle application of chlorine bleach and trisodium phosphate is only temporarily effective. To eliminate the problem the roof shingles may also be replaced with asphalt shingles containing algaecides and fungicides. Such replacement is costly, cumbersome and economically undesirable.  
         [0010]     The present invention provides algaecidal and fungicidal designs for asphalt and non-asphalt roof shingles and other building materials accomplished by a simple, economically advantageous design which does not require replacement of roof shingles on existing buildings and/or can be used in new roof construction, and does not require roofing or siding containing algaecidal or fungicidal compounds or compositions.  
       SUMMARY OF THE INVENTION  
       [0011]     The present invention provides for an algae and fungi-retardant apparatus comprising a strip attached to the building material on a side, roof or attached below and adjacent to a roof ridge vent. The strip has one or more lengths to cover a length of a roof or side; preferably a width of from about 1/16th to 12 inches but maybe several feet; and preferably a thickness of from about 1/64th to 2 inches or more. The strip can be secured to an asphaltic or non-asphaltic roof covering in a position designed to provide for precipitation to flow over the strip and over the roofing material. The strip can be positioned adjacent to the external baffle of a roof ridge vent and secured thereto by the use of adhesives, nails, screws or other known methods. Alternatively, the strip may be used as a flashing, attached to a flashing, and any combination of the above. The strip can further be positioned on a building side that is exposed to precipitation flowing over it. As precipitation flows over the strip, the ions released from the strip flow over the building material and reduce or eliminate the growth of algae and fungi on the building material.  
         [0012]     The present invention is convenient and economical for use on existing asphalt shingles with and without algaecidal and fungicidal compositions incorporated therein, it may also be used on new shingles covering newly constructed roofs with or without algaecidal and fungicidal compositions incorporated therein. The present invention may also be used on non-asphaltic roofs, including single ply-membranes, roofing tiles, roll roofing, built up roofing, commercial cap sheets, modified bitumen cap sheets, shakes and sidewalls. Further, the invention may be used on different siding materials. Besides the materials already mentioned, this invention may be used with any building material susceptible to fungus and mold growth including but not limited to modified bitumen APP (Atactic Polypropylene) membranes, modified bitumen SBS (Styrene butadiene styrene) membranes, TPO (Thermoplastic olefin membrane), PVC (Polyvinyl chloride), and EPDM (Ethylene propylene diene terpolymers) membranes, vinyl, fiber cement, and other siding materials.  
         [0013]     The fungus strip may be used with any type of roof and with a variety of ridge vents. However, when used on a ridge vent it is preferred to use the strip with a specific plastic ridge vent that is described hereunder. Other ridge vents include but are limited to those embodied in U.S. Pat. Nos. 4,924,761; 4,957,037; 5,095,810; 5,704,834; 5,772,502; and 6,227,963. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0014]      FIG. 1  is a schematic exploded view of a plastic ridge vent attached to a roof;  
         [0015]      FIG. 2  is a schematic exploded perspective view of a plastic ridge vent attached to a roof;  
         [0016]      FIG. 3  is a perspective view of the plastic ridge vent mounted on a section of a building roof;  
         [0017]      FIG. 4  is a cross-sectional view of the plastic ridge vent and one embodiment of the fungus strip;  
         [0018]      FIG. 5  is a cross-sectional view of the plastic ridge vent and a second of the fungus strip;  
         [0019]      FIG. 6  is a cross-sectional view of the plastic ridge vent and a third embodiment of the fungus strip.  
         [0020]      FIG. 7  is a schematic view of fungus strip applied to a shingled roof.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]      FIG. 1  shows a schematic exploded perspective view of a plastic ridge vent  10  attached to a roof  12  to which fungus strip  1  is secured. The fungus strip  1  is positioned longitudinally and parallel to the plastic ridge vent which comprises external baffles  50  and  50 ′. Fungus strip  1  terminates in ends  2  and  2 ′ projecting at about 90° therefrom. Preferably, the fungus strip can be bent and secured to roof  12  underneath the external baffles  50 ,  50 ′ by nails or glue. Preferably, the fungus strip comprises tin or zinc. The thickness of the strip is typically 1/16 th  to 2 inches or more.  
         [0022]      FIG. 2  shows a schematic exploded perspective view of a plastic ridge vent  10  attached to a roof  12  to which fungus strip  1  is secured. The fungus strip  1  is positioned longitudinally and parallel to the plastic ridge vent which comprises external baffles  50  and  50 ′. Fungus strip  1  terminates in ends  2  and  2 ′ projecting at about 90° therefrom and has a vertical portion and a horizontal portion that are not necessarily 90° from each other. In a preferred embodiment, the fungus strip  1  is marked with nail or glue points  5  on its horizontal portion to aid installation. Preferably, the fungus strip comprises tin or zinc. The width of the horizontal portion is typically 1/16 th  to 12 inches or more, the height of the vertical portion may be 1/16 th  to 4 inches, while the thickness of the strip is typically 1/16 th  to 2 inches or more.  
         [0023]      FIG. 3  is a perspective view of the plastic ridge vent  10  mounted on a section of a building roof  12 . Building roof  12  comprises a plurality of crossbeams  14  and  14 ′ joined together at  16  to form the structural support for building roof  12 . Plywood decking  18  and  18 ′ are laid over the cross-beams. The plywood decking is covered with shingles  20  and  20 ′. The plywood decking and covering shingles on the plywood decking do not completely cover the roof; at the ridge of the roof there is an opening or ridge slot  22  that serves as an vent for air from space below the ridge  24 . The ridge slot exists between each pair of cross-beams defining a continuous space under the peak of the roof so that the attic air can be vented to the outside. While the ridge slot provides for ventilation of the attic space, it also allows entry of rain, snow, insects and debris to enter into the attic space. To prevent such entry, as well-known in the art, a ridge vent covers the ridge slot and at least partially overlaps the plywood deck and shingles of the roof. The overlap ensures that precipitation does not migrate toward the peak of the roof and enter the attic space or space below the ridge.  
         [0024]     The ridge vent  10  covers a slot at the peak of the roof and provides for proper ventilation of attic space  24  while preventing entry of moisture, insects and other elements thereinto without substantially affecting the maximum ventilating capability of the gap if left uncovered.  
         [0025]     The plastic ridge vent comprises a unitary panel  26  that is disposed over the ridge of the roof. The vent can be contoured to the configuration of the roof angle, which can be of about 10° to 45° or more since the plastic material of which the panel is made can be contoured to any desired angle on the roof. While the unitary construction is preferred, the panel may be constructed of two isometric panels joined together at the peak of the roof or other suitable means. Accordingly, the plastic ridge vent has a top face and bottom face. The vent is bent at central point line  28  so that the panel conforms to the peak of the ridge. To obtain a smooth configuration, plastic ridge vent  10  can be bent not only at central point line  28  but also at linear point lines  30  and  30 ′. The fungus strip  1  is applied to the external baffles  50  and  50 ′ of the ridge vent  10 .  
         [0026]      FIG. 4  is a cross-sectional view of the fungus strip  1 , nailed  55  to the baffle  50  of the ridge vent  10  (the ridge vent partially shown). In  FIG. 4  the strip terminates at the top  60  and bottom  62  of the baffle  50  and is the approximate width and contour of the baffle.  
         [0027]      FIG. 5  is a cross-sectional view of the fungus strip  1  nailed to the roof  12  by nail  55  which also secures the ridge vent  10  (partially shown). In this embodiment the fungus strip  1  is a continuous strip from the top of the baffle  60  under the louvers  32  of the louver portion of the ridge vent  10  and beyond the nail portion  64  of the ridge vent  10 .  
         [0028]      FIG. 6  is a cross-sectional view of another embodiment of the fungus strip  1  nailed to the roof  12  by nail  55  which also secures the ridge vent  10  (partially shown). In this embodiment the fungus strip  1  is substantially planar and is of a width such that it extends beyond the baffle  50  at one end and beyond the nail portion on the other end.  
         [0029]     It is not necessary that the fungus strip follow the contour of the baffle, it may be substantially planar and it may also rise above or below the baffle top  60 .  
         [0030]     In  FIG. 7  the fungus strip  1  is applied to a shingled roof  100  without a ridge vent. The strip may be applied to any part of the roof without regard to a vent or venting system. Additionally, the strip may be applied to a non-asphaltic roof. The strip may be attached to the roof through known means including adhesives, double sided tape, and fasteners including nails and screws. Further, the building materials may be in various forms including, for example, asphalt roofing shingles, non-asphaltic roofing shingles, roofing tiles, roll roofing, commercial cap sheets, modified bitumen cap sheets, shakes and sidewalls.  
         [0031]     Accordingly, it should be readily appreciated that the device and method of the present invention has many practical applications. Additionally, although the preferred embodiments have been illustrated and described, it will be obvious to those skilled in the art that various modifications can be made without departing from the spirit and scope of this invention. Such modifications are to be considered as included in the following claims.