Abstract:
A self-aligning roofing shingle with a shingle body defining a top edge, and at least two spaced locating features proximate the top edge of the shingle body, each locating feature defined by a projection and an indentation, wherein a projection of one shingle in a first course of shingle locates in an indentation of a mating shingle in an adjacent course of shingles.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority of Provisional application Ser. No. 60/684,090 filed on May 24, 2005. 
     
    
     FIELD OF THE INVENTION  
       [0002]     This invention relates to roofing shingles.  
       BACKGROUND OF THE INVENTION  
       [0003]     Traditional asphalt roofing shingles are rectangular and have two spaced slots along their bottom edge. The shingles are laid such that the slots of shingles in adjacent courses are fully offset.  
         [0004]     In order to properly install shingles, each course musty be plumb and parallel to the adjacent courses. Doing so requires some degree of skill, which makes shingles relatively difficult and expensive to install.  
       SUMMARY OF THE INVENTION  
       [0005]     It is therefore and object of this invention to provide a roofing shingle that is self-aligning with shingles located above it in an adjacent course, so that there is no need to manually align the shingles in order to properly shingle a roof.  
         [0006]     This invention comprises an asphalt-style roofing shingle with a series of locating features (which may comprise tabs) that properly align the shingles, one above the other, as the courses are laid down on the roof. In the preferred embodiments, the alignment is accomplished by adding features proximate to or extending from the normal upper edge of the shingle. When the next course is laid down over the shingle, the features interlock. This ensures proper alignment of the shingle and also helps hold them in place while they are being nailed. The result is that the shingles are easier to install, which saves installation time.  
         [0007]     The invention features a self-aligning roofing shingle with a shingle body defining a top edge, and at least two spaced locating features proximate the top edge of the shingle body, each locating feature defined by a projection and an indentation, wherein a projection of one shingle in a first course of shingle locates in an indentation of a mating shingle in an adjacent course of shingles. The shingle body may be generally rectangular. The self-aligning roofing shingle may further comprise a locating strip carrying the locating features and coupled to the shingle. The locating strip may run the length of the shingle. The locating strip may carry a series of regular projections and indentations. The locating strip may have a generally serpentine shape, with projections located above indentations. The projections may have straight edges, or may be rounded, or any other shape. They can be made by die-cutting traditional shingle material. The shingle may have spaced slots along its lower edge, and the locating features may be arranged such that the shingles in adjacent courses can be aligned such that the slots are misaligned.  
         [0008]     A roofing shingle system may comprise a number of courses of these self-aligning roofing shingles, and further comprise a starter strip located underneath the first course of the shingles.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]     These and other objects and features of the invention will become more apparent based upon the following description together with the accompanying drawings, in which:  
         [0010]      FIG. 1A  is a front view and  FIG. 1B  a back view of one embodiment of the shingle of the invention;  
         [0011]      FIGS. 2A and 2B  are similar views of another embodiment of the invention;  
         [0012]      FIGS. 3A and 3B  are similar views of yet another embodiment of the invention, with  FIG. 3C  being a side view of this embodiment;  
         [0013]      FIGS. 4A and 4B  are similar views of yet another embodiment of the invention, with  FIG. 4C  showing a starter strip that can be used with the invention;  
         [0014]      FIGS. 5A and 5B  are similar views of yet another embodiment of the invention;  
         [0015]      FIG. 6  shows the shingles of the invention in place on a roof; and  
         [0016]      FIG. 7  is an exploded view similar to that of  FIG. 6  that helps to illustrate the manner in which the shingles are laid on the roof 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]     The invention is shown conceptually in  FIGS. 1A and 1B , in which shingle  10  is a typical 3-tab shingle with slots  18  and  19  in the lower half of the shingle. Typical asphalt shingles have parallel bottom edge  13   a  and top edge  13   b.  In the invention, a locating strip  12  is added to the back of the shingle proximate upper edge  13   b.  Strip  12  has a series of regularly-spaced projections  14  and  16  and mating indentations  15  and  17 . In this embodiment, strip  12  is formed with a regular series of projections along the top and matching indentations along the bottom. This can be created by forming, such as by die cutting, a strip of asphalt shingle material to create the serpentine shape. The strip is then attached to the back of the shingle with adhesive. Alternative manufacturing options such as directly forming the shingle with the locating features therein are possible. However, another advantage of the added strip design is that, as shown in the side view of  FIG. 3C , the additional strip adds to the thickness at the top of the shingle such that when the shingle is laid on top of another shingle, the added thickness maintains the top surface of the shingle in more or less a single plane. This helps to prevent cupping of the shingles, and thus provides an improved finished appearance as well as potentially a longer life and more resistance to wind damage.  
         [0018]      FIGS. 2-5  show alternatives for the unlimited possible shapes of interlocking locating features, as well as location of the features either projecting above the top edge of the shingle or located just below or at the top edge of the shingle. Locating strip  22  of shingle  20 ,  FIG. 2 , is located below the straight top edge of the shingle. Strip  34  of shingle  30 ,  FIG. 3 , illustrates a larger quantity and different shape for the projections  32 . Strips  42  and  52  of shingles  40  and  50 ,  FIGS. 4 and 5 , are additional examples.  FIG. 4C  shows starter strip  44  that can be used in the invention. The projections and indentations can have any convenient shape, such as the straight-edged or rounded geometric shapes shown in the drawings, or other more curvilinear shapes.  
         [0019]     By properly sizing and locating the shingle locating features such that the mating features of overlapping shingles interfit with one another, as a new course of shingles is laid over an existing course, the shingles are properly aligned such that the slots  18 ,  19  alternate as shown in layout  80 ,  FIG. 6 . The relative shingle locations are shown in more detail in layout  90 ,  FIG. 7 , with overlaid vertical axes illustrating the relative locations of shingles  30   a  and  30   b.    
         [0020]     Also shown in  FIG. 7  is another advantage in which starter strip  44  can be laid down at the bottom edge of the roof. Strip  44  can have a width that is about the same as the width of shingle  30   a  from its bottom edge up to the bottom of the locating strip that is added to the back of the shingle. In this case, the starter strip fills in the space between this portion of the back of the shingle and the roof, thus presenting a flat surface to the roof This strip would typically be about 7 inches high so that the underlayment is not exposed beneath the slots of the first course of shingles when they are laid over this starter strip. As an alternative, regular straight-edge shingles can be used instead of this special starter strip, as is typically done today.  
         [0021]     The invention accomplishes interlocked shingles that are level and plumb across both the width and height of the roof, thereby substantially facilitating installment and also creating a better looking end result. In order to accomplish this result, the shingles should have at least two spaced locating features proximate their top edge, so that the shingle laid on top of such shingle is positively located by the at least two locating features.  
         [0022]     Although specific aspects of the invention are shown in some drawings and not others, this is not a limitation of the invention. Rather, the invention is defined by the following claims.