Abstract:
Disclosed herein is a multi-use building structure and method of assembling same. The building has its major components preferably made of twin sheets of plastic resin, each sheet formed to define different inner and outer surfaces. The building includes unique fasteners and connections facilitating quick and easy assembly for use and disassembly for shipping. The building may be used for different purposes with simple modifications, including a portable toilet, ticket booth, shelter, and storage shed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of provisional application Serial No. 60/120,828, filed Feb. 19, 1999. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     (Not applicable). 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to a plastic resin building, for example, an outhouse or bus stop, that is easily assembled, durable, efficiently moldable and transportable in bulk, washable and portable when assembled. 
     2. Discussion of the Prior Art 
     Outdoor shelter structures, such as portable outhouses, are commonly rented and used for special events, such as parties, festivals or concerts, as well as at job sites or other locations where people are gathered temporarily. Prior art portable outhouses are, for the most part, unsightly from the outside and unpleasant on the inside. 
     Typically, portable outhouses are transported fully assembled and in large numbers to their end use sites. They are generally rough handled. For example, it is not uncommon for them to be dropped off of a flatbed truck. Therefore, they must be very durable. In addition, the large size and low weight of an assembled portable outhouse, relative to the payload capacity of a truck, makes shipping them assembled costly. As a result, some structures have been manufactured to be shipped in separate components and assembled on site by either the supplier (i.e., the rental company) or the end customer. The assembly process is typically difficult and time consuming, since there are often numerous components that cannot be easily aligned. The assembly time and cost is further exacerbated when a large number of units are involved. 
     Additionally, the door latches on existing structures are typically small metal hooks, catches or sliding bolts that are difficult to secure in place, prone to breaking or misoperation and are difficult to operate from outside the structure. The ability to operate the latch from outside the structure is particularly important for opening the door in the event a small child or incapacitated person was locked inside. It is also useful to be able to lock the doors from the outside when transporting fully assembled units to keep the doors from opening and slamming shut. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a multi-use building which has its major components moldable from plastic resin. Aspects of the invention make the components compactly shippable and easily assembled. Once assembled, the building is aesthetically pleasing, low maintenance and durable. 
     The building may be used for different purposes with simple modifications, such as an outhouse, bus stop shelter, ticket booth, sentry hut and storage shed. If used as an outhouse, the building walls are built around a septic tank, which also aids in the assembly process by holding up three sides of the building before the sides are permanently secured. Once they are permanently secured, the walls secure the tank, with no additional attachment of the tank needed. The sides are easily attached to the base and roof using specially molded-in receivers, which permit receipt and seating of the fasteners without complete removal of the fasteners, which facilitates one-person assembly of the building. Side edges of each wall are attached to the side edges of the adjacent walls at the corners of the building using a plastic extrusion, and the edges inter-fit with one another to reduce racking of the building. The tank itself also features one-piece molding, with subsequent cutting into two pieces, each of which is nestable with other pieces of the same kind for compact shipping and easy assembly. 
     Using a double walled molding method for the walls of the building, spaces are created between the inner and outer layers of the walls into which a sheet can be inserted. The sheet may be a screen to provide for ventilation or a transparent panel to provide a window. The portions of the two layers of the wall are cut out in an area smaller than the inserted sheet and the edges of the inserted sheet between the two layers of the wall are trapped by welds between the two layers, or by fasteners which may be threaded through the two layers. The area which may be cut out to make a window if desired, can be made flat, so that if it is not cut out, signage, such as the sign of the outhouse rental company, can be placed over it for display. 
     In another aspect, the outer layer is molded to have a design, for example siding, bricks, stones or other like design. The ridges of the design reinforce the wall because the shape creates solid sections which extend horizontally and also because where the outer layer is recessed from the exterior of the building, the outer layer is fused to the inner layer. The inner layer is preferably made generally flat and smooth, particularly if the building is used as an outhouse, for easy cleaning. 
     In another aspect, the door and door panel include several unique features. One is that the door and door frame are molded with a living hinge in the portion which becomes the door frame. Cutting the door frame into two pieces after cutting the door from the door panel is not necessary in this design, as the living hinge flexes to permit pulling the two sides of the door frame together to create side-to-side overlap with the door. Maintaining this connection between the two sides of the door frame helps keep the two sides aligned during assembly and reinforces the building. The living hinge also creates a coat hook inside the building. In this connection, a keystone can be molded as part of the roof to cover the seam between the two sides of the door frame, at the outer end of the living hinge. 
     In another aspect concerning the door, the door has a plastic molded latch which is large, washable, easy to assemble and durable. The latch and door designs cooperate to provide their own stops, and a stick-on indicator can be applied to the latch so that it indicates to a person standing outside of the building whether the latch is latched or unlatched. A detent may also be provided between the door and the latch to secure the latch in an unlatched position. Should the latch accidentally close however, the latch is made with a slot which is accessible from the outside so that the latch can be unlatch from the outside. 
     The door is also molded with signage holders. If used as an outhouse, it is useful to identify which gender the outhouse is intended for, or whether both genders may use it. Thus, a gender card holder is molded into the outer surface of the door. For advertising, a business card holder is molded into the outer surface of the door, for example, so that the outhouse rental company can put its card or cards in the holder. 
     The roof also includes features to make the building well lit by daylight and leak resistant in a rain storm. The roof has a skylight attached to it, and rain gutters are molded into the roof at the upper corners of the skylight and down along the sides of the skylight to channel rain water which may leak past the skylights away from the opening in the roof beneath the skylights. Thereby, leakage through the roof is reduced, while providing good daylight lighting. 
     The foregoing and other objects and advantages of the invention will appear from the following description. In this description reference is made to the accompanying drawings which form a part hereof and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a building of the present invention; 
     FIG. 2 is a front plan view of the building of FIG. 1; 
     FIG. 3 is a side plan view of the building of FIG. 1; 
     FIG. 4A is a fragmentary front plan view of the gender sign holder and business card holder; 
     FIG. 4B is a cross sectional view taken along line  4 B— 4 B of FIG. 4A; 
     FIG. 5A is an enlarged fragmentary exploded perspective view of a side panel and the base, showing the assembly of a side panel to the base; 
     FIG. 5A is an enlarged fragmentary perspective view of a side panel and base, showing one connection of the side panel to the base; 
     FIG. 5C is a cross-sectional view taken along line  5 C— 5 C of FIG. 5B showing the connection of the side panel to the base; 
     FIG. 5D is a cut-away perspective view showing a side panel joined to the base; 
     FIG. 5E is a cross-sectional view taken along line  5 E— 5 E of FIG. 5D; 
     FIG. 6A is a fragmentary exploded perspective view of the edges of the side panels; 
     FIG. 6B is a cross-sectional view taken along line  6 B— 6 B of FIG. 6A; 
     FIG. 6C is a cross-sectional view taken along line  6 B— 6 B of FIG. 6A, showing the edges joined with a corner piece. 
     FIG. 6D is a detail view of the area within arc  6 D— 6 D of FIG. 6C; 
     FIG. 6E is a cross-sectional view taken along line  6 E— 6 E of FIG. 6C, showing an interlock on the side panel flanges (but not the corner piece); 
     FIG. 7A is a fragmentary cross-sectional view taken along line  7 A— 7 A of FIG. 3, showing a segment of a side panel with vents and a mesh screen sandwiched by layers of the panel; 
     FIG. 7B is a fragmentary cross-sectional view taken along line  7 B— 7 B of FIG. 3 of the roof and a side panel, showing the vents and mesh screen; 
     FIG. 7C is a detail view of one roof-side panel connection from the outside; 
     FIG. 7D is a cross-sectional view taken along line  7 D— 7 D of FIG. 7C, showing the roof-side panel connection; 
     FIG. 8A is a fragmentary exploded perspective view of an interior portion of the side panels and corner of the elimination tank, showing the assembly of a tab on the tank into a cut-out slot in a T-projection of the side panels; 
     FIG. 8B is a view like FIG. 8A, but showing the assembly; 
     FIG. 8C is a cross-sectional view taken along line  8 C— 8 C of FIG. 8B; 
     FIG. 9A is a perspective view of the elimination tank of the outhouse embodiment of the outdoor structure of FIG. 1; 
     FIG. 9B is an exploded perspective view of the tank of FIG. 9A; 
     FIG. 9C is a cross-sectional view of the bottom of the tank of FIG. 9A taken along line  9 C— 9 C of FIG. 9B; 
     FIG. 9D is a fragmentary perspective view of one connection joining the top and bottom sections of the tank of FIG. 9A; 
     FIG. 9E is a fragmentary cross-sectional view along line  9 E— 9 E of FIG. 9A, showing the overlapping seam between the top and bottom sections of the elimination tank of FIG.  9 A and where the seam can be cut to separate the sections; 
     FIG. 9F is a fragmentary cross-sectional view taken along line  9 E— 9 E of FIG. 9A before being separated at the cut-line; 
     FIG. 9G is a fragmentary cross-sectional view along line  9 F- 9 G of FIG. 9A, showing the connection at the ledge portion of the overlapping seam between the top and bottom sections of the tank of FIG. 9A; 
     FIG. 9H is a fragmentary cross-sectional view along line  9 G— 9 G of FIG. 9A before being separated at the cut-line; 
     FIG. 9I is a side plan view of nested elimination tank bottoms; 
     FIG. 9J is a side plan view of nested elimination tank tops; 
     FIG. 9K is an exploded perspective view an alternative embodiment of the tank of FIG. 9A; 
     FIG. 10A is a front plan view of a one-piece molded door and door frame panel of the invention before the door is cut out; 
     FIG. 10B is a fragmentary front plan view of the front panel after the door is cut out and the remaining door frame is contracted inwardly to overlap the door at the edges; 
     FIG. 10C is a cross-sectional view taken along line  10 C— 10 C of FIG. 10A before the door is cut out; 
     FIG. 10D is a cross-sectional view taken along line  10 D— 10 D of the one-piece front panel of FIG. 10A before the door is cut out, showing the flexible living hinge portion of the door frame panel as molded; 
     FIG. 10E is a cut-away cross-sectional view taken along line  10 E— 10 E of the living hinge portion of the door frame panel of FIG. 10B secured in the folded position as needed to properly frame the door; 
     FIG. 10F is a cross-sectional view taken along line  10 F— 10 F of FIG. 2; 
     FIG. 10G is a cross-sectional view taken along line  10 G— 10 G of FIG. 2 showing the hinging of the door to the door frame panel; 
     FIG. 10H is a cross-sectional view taken along line  10 D— 10 D of FIG.10A showing an alternate embodiment of the living hinge before assembly; 
     FIG. 10I is a cross-sectional view taken along line  10 I— 10 I of FIG. 10H; 
     FIG. 11A is a detail view of the area indicated by arc  11 A— 11 A of FIG. 2 of the door and front panel, showing the door latch in phantom in the closed position; 
     FIG. 11B is a view like FIG. 11A but showing the door latch in phantom in the open position; 
     FIG. 11C is a cross-sectional view taken along line  11 C— 11 C of FIG. 11A, showing the door latching mechanism; 
     FIG. 11D is a fragmentary rear view of the door and front panel of FIG. 11A, showing the door latch from inside the outdoor structure; 
     FIG. 11E is a fragmentary cross-sectional view along line  11 E— 11 E of FIG. 11A; 
     FIG. 11F is a cross-sectional view taken along arc  11 F— 11 F of FIG. 11D, showing the latch on each side of the latch stop dimple; 
     FIG. 11G is a perspective view of the door latch; 
     FIG. 11H is a perspective view of an alternate door latch having a recessed grip handle; 
     FIG. 12A is a front view of the door and door frame panel from inside the structure; 
     FIG. 12B is a fragmentary top cross-sectional view taken along line  12 B— 12 B of FIG. 12A, showing the door tensioning mechanism; 
     FIG. 13A is a fragmentary perspective assembly view of the roof and skylight cover of the building of FIG. 1; 
     FIG. 13B is a fragmentary side cross-sectional view taken along line  13 B— 13 B of FIG. 13A; 
     FIG. 13C is a fragmentary cross-sectional view take along line  13 C— 13 C of FIG. 13A; 
     FIG. 14A is an exploded assembly view of the base and tank of the building of FIG. 1; 
     FIG. 14B is an exploded assembly view showing the assembly of the side panels onto the base and tank of FIG. 14A; 
     FIG. 14C is an exploded assembly view showing the assembly of the door frame panel and door onto the base and the assembly of the corners onto the side panels of FIG. 14B; 
     FIG. 14D is an exploded assembly view showing the assembly of the roof onto the door frame and side panels of FIG. 14C; 
     FIG. 15A is a perspective view of a bus stop shelter embodiment of the building of FIG. 1 having side panel and door windows; 
     FIG. 15B is a perspective view of a bus stop shelter embodiment having larger side panel windows; 
     FIG. 15C is a fragmentary perspective view of the bus stop shelter embodiment of FIG. 15A showing a bench inside the shelter; 
     FIG. 15D is a front cross-sectional view of the bench taken along line  15 D— 15 D of FIG. 15C; 
     FIG. 15E is a cross-sectional view of the window taken along line  15 E— 15 E of FIG. 15A; 
     FIG. 15F is a front cut-away view of the window and opening in FIG. 15A taken along line  15 F— 15 F of FIG. 15E; 
     FIG. 16A is a cross-sectional view similar to FIG. 6C of an alternate embodiment of the corner connections; 
     FIG. 16B is a cross-sectional view similar to FIG. 16A of an alternate embodiment of the corner connections; and 
     FIG. 16C is a cross-sectional view similar to FIG. 16A of another alternate embodiment of the corner connections; 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The outdoor structure, or building, of the present invention is indicated generally by reference number  20  of FIG.  1 . In general, the outdoor structure  20  comprises a base  22 , side panels  24 , a door frame panel  26 , a door  28  and a roof  30 . As best shown in FIG. 14A, the base  20  is made of a plastic wood material (solid recycled plastic) and has two transverse feet  32  that are slightly longer than the structure  20  and approximately 4″ wide. The feet  32  have front and rear tapered ends  34 , oriented to taper downward toward the structure  20  so as to facilitate sliding the structure  20 . The feet  32  support transverse and lateral members  36  fastened together to form an essentially rectangular framework  38 . The framework  38  in turn supports a floor board  40 , roughly ½″ thick and covering approximately the front half of the framework  38 . The rear half of the framework  38  supports the elimination or septic tank  42 , shown in FIG.  14 B and discussed in detail below. 
     In general, one side panel  24  is attached at its bottom to each of the rear lateral and two transverse members  36 , which form the perimeter of the framework  38 . Bolts  44  fasten the panels  24  to the framework  38  at slots  46  located along the lower edge of the panels  24 . The door  28  is mounted to the door frame panel  26  by hinges  48 , and the door frame panel  26  is attached to the front lateral member  36  by threaded fasteners  49 . Longitudinal corners  50  join adjacent longitudinal edges  52  of the panels  24  and  26 . Finally, the roof  30  is joined to the panels  24  by bolts  44  and washers  55  through slots  56  in the roof  30  and bores  58  (see FIG. 7D) in the upper edge of the panels  24  and fastened to nuts  57 . 
     Having provided the general construction of the outdoor structure  20 , the components of the structure  20  will now be described in detail. Referring to FIGS. 1-3, the panels  24  and  26  and door  28  are twin-sheets of plastic resin, preferably a high molecular weight HDPE polyethylene, thermally formed by a blow molding or pressure molding process as is known by those skilled in the art. As can be seen in FIG. 8 for example, the thermally formed sheets are molded such that the two layers join at some points and are spaced apart at various distances elsewhere. The three side panels  24  are formed identically, and therefore, are interchangeable. It should be noted that the invention is not necessarily limited to being practiced by blow molding or twin sheet thermal forming manufacturing processes. 
     The twin-sheet panels  24  and  26  and the door  28  are formed of inner  59  and outer  61  walls to provide interior  60  and exterior  62  surfaces of different configurations, that are welded together where they meet, as is well known. The interior surfaces  60  of the panels  24  and  26  and door  28  have an aesthetically pleasing smooth, seamless surface. Preferably, the exterior of panels  24  and  26  have a surface  62  that resembles the exterior of a house, such as siding (as shown in FIG.  1 ), clapboards, timbers, bricks or stones, which looks nice and provides reinforcement. FIGS. 1-3 also show that the walls  60  of the panels  24  are molded to resemble various configurations of window frames  64 , the pane portion  65  of which may be cut out and replaced with a translucent or transparent plastic sheet if desired or covered with signage. Similarly, the walls  60  can be formed to have an exterior surface  62  defining other features, such as a crescent moon  66  (or any other symbol), gender sign frame  68 , business card frame  70  and wooden panels  72 . As shown in FIGS. 4A and 4B, frames  68  and  70  define recessed surfaces  69  and  71  for receiving cards indicating the gender designation of the structure  20  and the event sponsor, respectively. The frames  68  and  70  also have slots  73  spaced along the longitudinal sides of the frames  68  and  70  for receiving tabs (not shown) of transparent plastic covers (not shown) sized to fit within the frames  68  and  70 . 
     FIGS. 5A-5E provide an enlarged view of one interconnection between the panels  24  and the framework  38  of the base  22 . Referring to FIG. 5A, receivers  46  are recessed into the exterior surface  62  of the panels  24 . The receivers  46  have a recessed circular portion  74  with a through bore  76  at its center. An arcuate segment of the circular portion  74  is broken to define a radial opening  78  extending from the center bore  76  through to the bottom edge of the panel  24 . Each side panel  24  slides over the bolts  44  in the base frame  38  through the openings  78  in the slots  46 . As shown in FIGS. 5B-5C, the center bore  76  is sized to fit over the bolt  44  and the recess  74  is sized to capture a washer  55  on the bolt  44 . When the bolt  44  is tightened, this connection prevents the panels  24  from being longitudinally separated from the base  22 . To accomplish this, shoulders  75  border the recess  74  adjacent the lower edged washer  55  to prevent the side panel  24  from being pulled off of the base  32  when the bolt  44  is tightened. Ramps  77  lead up to the apex of shoulders  75 , to facilitate sliding the receiver  46  under the washer  55 . The mouth  79  of the receiver  46 , at the lower edge of the panel  24 , also flares outwardly to ease assembly. 
     Referring now to FIGS. 6A-6E, the longitudinal edges  52  of the panels  24  and  26  have a channel  82  formed between a longitudinal wall  84  and a longitudinal tubular member  86 , extending in the plane of the panels  24  and  26 . The tubular members  86  have barbs  87  which extend partially over the channel  82  and are longitudinally spaced apart approximately twelve inches along a corner edge  89 . Longitudinal flanges  88  extend outwardly at approximately 45 degrees from the plane of the panels  24  and  26 . Molded within the flanges  88  at the left edges  52  are longitudinal projections  90 , having a triangular lateral cross-section, which extend toward the panels  24  and  26 . Molded within the flanges  88  at the opposing edges  52  are longitudinal projections  92  having a triangular cross-section sized to nest within the projections  90  and interlock adjacent panels  24  and  26 , as shown in FIG.  6 E. Such interlocking helps racking of the panels  24  relative to one another. Referring to FIG. 6C, longitudinal corners  50 , made of extruded plastic approximately the length of the panels  24  and  26 , have a generally C-shaped cross-section that forms a substantially right angle between two long legs  94 , each having a short leg  96  at a substantially right angle to it. The short legs  96  have inwardly facing full-length barbs  97  along their free edge  99  which cooperate with the barbs  87  to secure the corner extrusion  50  to the side panel edges. Each panel  24  and  26  is joined to an adjacent panel  24  and  26  by mating the projections  90  and  92  and sliding the short legs  96  of the corner  50  within the channels  82 , as shown in FIGS. 6C-6E. The projections  90  and  92  and the corners  50  increase the structural integrity of the structure  20  and prevent the panels  24  and  26  from separating longitudinally, laterally or transversely. As shown in FIGS. 5D and 5E, before the corners  50  are assembled, the panels  24  are secured to the base  22  by bolts  91  inserted in bores  93  in side panels  24  and the transverse members  36  of the base  22 . The bolts  91  are secured by nuts  95  in cross-drilled bores  101  in the lateral member  36  of the base framework  38 . This arrangement also provides extra support to the base framework  38 . 
     As shown in FIG. 3, vents  98  are disposed in two rows at non-lapped sections near the top edge of the side panels  24 . Referring now to FIGS. 6A and 6B, the vents  98  are formed by cutting out rectangular openings  100  through the inner  59  and outer  61  walls of the side panels  24 . Rectangular sections of screen  102 , made of a wire or plastic mesh material which are larger than the openings, are slid between the vent openings  100  of walls  59  and  61  from the top of the panels  24 . The screen sections  102  rest upon a seam  104  below the vents  98  formed by the union of the inner  59  and outer  61  walls. 
     As shown in FIGS. 8A,  8 B and  14 B, the inner walls  59  of the side panels  24  are formed generally flat and smooth so as to be easily washable. However, on the lower portions of each is a T-projection  106  along the central lateral or transverse (depending upon the position of the panels) axis of the panels  24 . The T-projections  106  comprise a vertical member  108  having an essentially rectangular U-shaped cross-section and a cross member  110  extending the width of the panels  24  and terminating at tapered ends  112 . The cross member  108  defines a wing-like cross-sectional profile formed by a lower flat surface  114  joined at one edge to an upper, arcuate surface  116 . Formed into the downwardly facing flat surface  114  are lateral slots  118 . Each T-projection  106  has slots  118  that are either cut-out or formed in the lower flat surface  114  at an equal distance from the vertical member  108 . The length of the slots  118  is sized to any length necessary to receive lateral tabs  120  of the tank  42 . Accordingly, the slots  118  may be sized to receive individual tabs  120  in the tank  42 , as shown in FIGS. 8A-8C. Or, the slots  118  may extend the fill length of the T-projection cross member  110  to receive extended length tabs (not shown) or a single, continuous tab (not shown) extending from three sides of the tank  42 . Alternatively, the side panels  24  may be formed or cut-out to have lateral (or transverse) slits (not shown) instead of T-projections. The slits are sized to receive a rigid or flexible tank tab (not shown) between the inner  59  and outer  61  walls. As with the slots  118  in the T-projections  106 , the length of the slits may be of any length necessary to receive the tank tabs. 
     FIGS. 9A-9I illustrate the elimination tank  42 . The tank  42  comprises a top  122  and a bottom  124  which mate at a seam  126 . The bottom  124  has a substantially rectangular base  128 . Trapezoidal front  130 , rear  132  and side  134  walls extend upwardly as they taper outwardly from the base  128 . The outward taper of the walls  130 ,  132  and  134  permit multiple bottoms  124  to nest within each other, as shown in FIG.  9 J. This nesting reduces the space occupied by the tanks  42 , and thereby reduces storage and shipping costs. 
     The front wall  130  is formed to include two tapered ankle flutes  136  having essentially parabolic, or alternatively rectangular, longitudinal cross-sections spanned by an arcuate surface  138 , which can be formed to have a raised splash-guard portion  139  at its center, as shown in FIG.  9 K. The ankle flutes  136  can extend to the bottom edge of the tank bottom  124 . At the top center of the flutes  136  is a recessed cavity  140  having a lateral ledge  142  spanning its top edge. The ledge  142  contains a bore  144  near its center. The side walls  134  are formed to define trapezoidal, wedge-like slats  146  alternatively projecting on a either side of a mean plane  148 , with the center slat  146  on the side of the mean plane  148  closest to the inside of the tank  42 . The rear wall  132  is similarly formed, with alternating trapezoidal slats  150  with the center slat recessed on the inside of the tank  42 . The wedge-like slats  146  and  150  taper longitudinally toward the base  128 . The configuration of the slats provides the tank  42  with sufficient structural integrity to support an above average-sized person. 
     In the preferred embodiment, the bottom  124  may also be molded to define a notched rear corner  154  having flat or slatted walls  156  that extend upwardly outward from the base  128 , as shown in FIGS. 9A-9C. As can best be seen if FIGS. 9D and 9J, a recessed mouse hole or channel  157  extends from the bottom of the ankle flute  136  nearest the notched corner  154  inward toward the rear wall  132 . The notched corner  154  provides space for an optional pump and the channel  157  provides space for plumbing (not shown) leading from the pump to a foot pedal (not shown) at the front of the tank  42  for use with a flushable tank. 
     The top  122  of the tank  42  has a top surface  156  sloping downward from back to front. The top surface  156  is bordered by front  158 , side  160  and rear  162  walls downwardly extending outward so as to overlap the top edge of the walls  130 ,  132  and  134  of the bottom  124  with a flanged lip  163  along the perimeter, as shown in FIG.  9 E. As with the bottom  124 , the outward taper of the walls  158 ,  160  and  162  allows multiple tops  122  to be nested within each other, shown in FIG.  9 I. 
     The front wall  158  defines concave  164  and arcuate  166  surfaces to match the flutes  136  and arcuate surface  138  of the bottom  124 . The concave surfaces  164  include cavities  168  at their center, spanned by a ledge  170  having a bore  172 , similar to those in the bottom  124 . The side  160  and rear  162  walls have wedge-like slats  174  formed to opposedly match the top edge of the bottom walls  132  and  134 . The wedge-like slats  174  of walls  160  and  162  have an increased thickness at a bottom edge  176 . 
     The side  160  and rear  162  walls extend upwardly beyond the top surface  156 . A lateral tab  120  projects upwardly from the top edge  178  of each side wall  160  adjacent the rounded front corners  170 . Two lateral tabs  120  project upwardly from the top edge  178  of the rear wall  162 , one on each side of the centered, recessed slat  180 . The tabs  120  are located to align with the slots  118  within the T-projections  106  of the side panels  24 , when the structure  20  is assembled. 
     Formed to project from the top surface  156  of the tank top  122  to a plane parallel with the base  128  of the tank bottom  124  are a cylindrical aperture  182  and a toilet seat  184 . The cylindrical aperture  182  defines an opening  186  for venting the contents of the tank  42 . The toilet seat  184  includes a level ring portion  188  defining an oblong opening  190  into the tank  42 . 
     The top  122  and bottom  124  are joined at the overlapping seam  126 . Referring to FIGS. 9D and 9G, a bolt  192  is inserted through the bores  172  and  144  in the top  122  and bottom  124 , respectively, and fastened into a nut  193  disposed within the cavity  140 . The tank  42  may be formed in two pieces by a suitable thermal forming process, or as one piece by, for example, rotational molding. FIGS. 9F and 9H illustrate a one-piece molded tank at the tank seam  126  before the top  122  and the bottom  124  are separated. The top  122  and bottom  124  are separated by cutting at the lines indicated by reference numbers  194  and  196 . 
     Alternatively, the tank bottom  124  may also be formed as shown in FIG. 9K with longitudinal fingers  199  extending upward on various outer slats  146 ,  150  of the side  134  and rear  132  walls, respectively. In this embodiment, the longitudinal slats in the tank top  122  alternately protrude on the inside and outside of the mean plane opposite to that of the slats in the tank bottom  124 . Thus, when the tank  42  is assembled, the fingers  199  fit against the outside of the inner slats in the tank top  122 . Longitudinal grooves  201  are formed of cut along the sides of the fingered slats to receive mating portions of outer slats in the tank top  122 . The grooves  201  in the rear wall  132  are formed or cut to extend below the grooves in the side walls  134  to allow the contents of the tank to drain from the rear in the event it was over-filled. This prevents the contents from flowing out at the front of the seam and contacting a person using the toilet. All other aspects of the tank  42  being as described above. 
     FIGS. 10A-10G generally illustrate the formation and connection of the door frame panel  26  and the door  28 . The door frame panel  26  and the door  28  are molded in a one-piece panel  198 , as shown in FIG. 10A with the molding flash removed, having a door portion  200 , first  202  and second  204  door frame portions, a living hinge  206  between the portions  202 , 204 , and waste material  208 . The door portion  200  is molded around a vertical support member  210  (shown in phantom in FIG.  11 C), preferably made of wood, disposed within a vertical channel  212  (shown in FIG. 12A) formed by the inner  59  and outer  61  walls along the handle side of the door portion  200 . A similar vertical wood support may also be provided on the hinge side of the door. The door frame portions  202  and  204  are molded around a support conduit  213  (e.g., steel conduit) disposed within a channel  215  (shown in FIG. 11C) on the handle side. A similar support conduit may also be on the binge side. The one-piece panel  198  has a greater lateral dimension (width) than the finished door frame panel  26  in order to account for the living hinge  206 , waste material  208  and overlap of the door and door frame. 
     The first  202  and second  204  door frame portions are joined to each other at the apex of the panel  198  by the living hinge  206 . The waste material  208  (shown shaded in FIGS. 10A and 10C) is the fusion of inner  59  and outer  61  walls in an inverted U-shape of generally uniform width around the door portion  200 , which leaves a free-edged bottom portion  214  that extends below, so as not to be flush with, the door frame portions  202  and  204 . Additional waste material  208  is disposed between the living hinge  206  and the door portion  200 . The waste material  208  is removed by any known means, such as by routing or using any other suitable cutter, and the door portion  200  is separated from the door frame portions  202  and  204 . 
     Referring to FIGS. 10D-10F, the living hinge  206  projects on the inside of the building  20 . The living hinge  206  has unfused inner  59  and outer  61  walls over the flexible portion of the hinge. Specifically, the living hinge  206  has a transverse cross-section defining generally parallel longitudinal sides  216  joined by an angled bottom  218  and a top  220  comprising a straight portion  222  and an S-curve portion  224 . Two lateral bores  226  are longitudinally spaced through the hinge  206 . 
     As formed, the living hinge  206  may have a lateral cross-section defining a rounded, inverted V-shape as shown in FIG.  10 D. The living hinge  206  may also be molded as shown in FIGS. 10H and 10I. Here, the hinge is formed in an inverted U-shape having two fused, straight sides  500  and a flexing unfused arcuate portion  502  joining the sides  500 . The inner wall  59  is formed to extend laterally from the top  504  of the sides  500  and so that it is fused to the outer wall  61  around the bores  226 . The inner wall  59  has a convoluted transverse cross-section that defines cavities  506  and support gussets  508  along the straight sides  500 . The gussets  508  work to prevent the sides  500  from bending with reduces unwanted flexing of the door panel  26 . The cavities  506  provide a place for inserting and tightening fasteners (not shown) in the bores  226  so as join the sides  500  of the living hinge  206  and align the door frame panel  26 . 
     In either case, the living hinge  206  is formed to have an opening  228  at a width  230 . The opening  228  is closed to a width  236  by fasteners  232  (shown in FIGS. 10D-10E as a bolts  232  and nuts  234 ) secured through the bores  226 . This forms a butt-joint  238  between the door frame portions  202  and  204  and creates the properly sized door frame panel  26 , as shown in FIG. 10B, while maintaining the door frame halves  202 , 204  in vertical alignment, and helping to maintain them in the same plane, relative to one another. Additionally, the S-curve  224  in the top  220  defines a hook for hanging hats, jackets or other articles of clothing. 
     Referring again to FIGS. 10E and 10F, the living hinge  206  may be cut longitudinally along line  600  to remove the door hook portion if desired. In this case, the door frame portions  202  and  204  are no longer integrally united, but are joined by bolts  232  and nuts  234 . The living hinge may be cut along line  600  either before or after assembly. 
     As shown in FIGS. 2 and 10G, the door  28  is hinged to the door frame panel  26  by three standard hinges  48  spaced longitudinally along the hinge edge  242  of the door frame panel  26 . The hinges  48  are secured to the door frame panel  26  and the door  28  by bolts  244  inserted into recessed bores  246  and tightened into nuts  248 . Once attached, the door  28  and door frame panel  26  overlap at the top and sides as shown in FIGS. 10F and 10G. 
     As best shown in FIGS. 11A-11B, the door  28  is also formed to include a rectangular handle  254  near the center of the free edge  256  of the door  28 . The handle  254  projects outward so as to define a pocket  257  for receiving a person&#39;s hand when opening the door  28 . Located laterally inward from the handle  254  are formed a circular recess  258  and a center opening  260  which receives a washer  262  and a bolt  264  so as to secure the inside door latch  266  to the door  28 . An arcuate occupancy window  268  is formed adjacent to the recess  258  to allow viewing of the red, “in use” or green, “not in use” portions of the indicator decal  270  adhered to the latch  266 . 
     As shown in FIG. 11C, the inner wall  59  of the door  28  is formed to include an inwardly projecting raised area  272  adjacent to, and partially defining, the pocket  257  of the door handle  254 . The raised area  272  also defines a circular recess  274  that is concentric with the center opening  260 . A bottom  276  of the circular recess  274  is fused to the outer wall  61  and is cut out to define the center opening  260  and the arcuate window  268 . Also, the bottom  276  defines an arcuate stop  278  projecting into the recess  274 . The stop  278  opposes the occupancy window  268  and defines a similar arcuate perimeter having first  280  and second  282  stop surfaces joined by a concave, arcuate surface  284 . Additionally, a latch stop  286 , comprising a dimple-like impression, is formed within the raised area  272 , located longitudinally above the arcuate window  268 . 
     As shown in FIGS. 11C and 11G, the latch  266  pivots along a transverse axis  288  through the center opening  260  in the door  28 . The latch  266  is formed to comprise a lever portion  290  having a smooth rounded end  292 . The lever portion  290  laps across a circular base portion  294  sized to fit within the circular recess  274  formed in the raised area  272  of the door  28 . Sides  296 , defining a frusto-conical segment, provide a smooth transition from the lever portion  290  to the circular base portion  294 . The lever portion  290  defines a circular recess  298  concentric with the circular base portion  294  for receiving a washer  300  and bolt  264  which secures the latch  266  to the door  28 . The circular base portion  294  extends transversely to a first surface  302  having an outer circumference  304  defined by the circular base portion  294  and an inner edge  306  defined by a concentric, convex arcuate portion  308  joining angled straight portions  310 . First  312  and second  314  transverse catch surfaces extend toward a second surface  316  having a perimeter defined by the outer circumference  304  of the circular base portion  294  and the inner edge  306  of the first surface  302 . A bore  318  is cut through the second surface  316  concentric with the lever recess  298 . A cylindrical bushing  320 , preferably made of a polyvinyl chloride material, has an outer diameter sized to tightly fit within bore  318  and an inner diameter sized to tightly fit around the lever recess  298  in the lever portion  290 . 
     Referring to FIGS. 11A,  11 B,  11 E and  11 G, a rectangular slot  322  is disposed radially within the second surface  316  at approximately the midpoint of the arcuate segment defining the second surface  316 . The slot  322  is sized to receive a small prying object, such as a coin, to open or close the latch  266  from outside the structure  20 . The occupancy-indicating decal  270  is affixed to the second surface  316  so that the red, unoccupied portion is located counter-clockwise from the radial slot  322  and the green, unoccupied portion is located clockwise from the radial slot  322 . 
     The base portion  294  of the latch  266  is inserted into the circular recess  274  of the door  28  so that the second surface  316  contacts the recess bottom  276 . The bolt  264  is inserted through the washer  300 , which fits within the outer circular recess  258  of the door  28 . The bolt  264  is then inserted through the opening  260  in the door  28  and the bushing  320  in the latch  266  and tightened to a nut  324  disposed within the lever recess  298 . 
     The latch  266  is formed so that the first catch surface  312  butts against the first stop surface  280  when the latch  266  is in an upright, unlatched position. Conversely, the second catch surface  314  is formed to butt against the second stop surface  282  when the latch  266  is in a horizontal, latched position. The abutting surfaces of the stops  280 ,  282  and the catches  312 ,  314  permit the latch  266  to pivot through approximately 90 degrees. 
     As shown in FIGS. 11D and 11F, the dimple  286  is positioned between the arc swept by the lever portion  290  of the latch  266 . The dimple  286  protrudes only far enough to prevent the latch  266 , when in the upright position, from latching unintentionally, as when shipping. Additionally, transverse walls  326  of the raised area  272  provide a structural support for the lever portion  290  so as to prevent intentional damage to the latch  266 . Also, a longitudinal strike plate  328  is formed in the inner wall  59  of the door panel  26  adjacent to the exterior door handle  254 . The strike plate  328  protrudes transversely to allow the latch  266  to pivot over it and lock the door  28 . 
     Referring to FIG. 11H, an alternate latch  266 A includes the circular base portion  294  and a lever portion  290 A having a lengthwise recess  291  providing space for a user&#39;s fingers. The lever portion  290 A of this latch  266 A also has a flat end  293 . 
     Referring now to FIGS. 12A-12B, the door  28  is also molded to include at least one lateral raised channel  330  for enclosing the door tensioning mechanism  332 . The door tensioning mechanism  332  can be constructed in any manner sufficient to allow the door  28  to open, but be biased in contact with the door frame panel  26 . For example, a door spring  334  can be affixed at one end to the door  28  and at the other end to a cable  336  that extends through an opening  338  in the edge of the door  28 . The free end  340  of the cable  336  has a ball-like element  342  that can be captured within a socket  344  disposed within a bracket  346  mounted near the inside corner of the door frame panel  26  by fasteners  348 . A second similar channel and closing mechanism may be provided near the bottom of the door, and a third could be added in the middle. 
     Referring now to FIGS. 13A-13C, the roof  30  is formed of one sheet of plastic having lateral and transverse dimensions slightly larger than the base  22  so that when assembled, it will overhang the side panels  24 . The roof  30  comprises an angled transverse ridge-line peak  350  that terminates at its sides at short longitudinal surfaces  352 . Lateral roof surfaces  354  slope downward from the longitudinal surfaces  352  to longitudinal side fascia  356 . A front gabled end  358  of the peak  350  and roof surfaces  354  terminate at a front fascia  360 . A back edge  362  of the peak  350  and roof surfaces  354  terminate at a transversely sloping roof surface  364  so that the roof surfaces  354  and  364  form two angled ridges  366  and the transversely sloping roof surface  364  terminates at a longitudinal rear fascia  368  that joins the side fascia  356 . A bottom edge of the fascia  356 ,  360  and  368  defines a raised trim  370 . The trim  370  leads into a raised keystone feature  372  at the apex of the front fascia  360 . The keystone  372  has a rounded top edge  374  joined to a substantially horizontal lower edge  376  by tapered, straight sides  378 . The keystone  372  extends downwardly to conceal the living hinge seam  206  in the door frame panel  26 , but not interfere with the movement of the door  28 , when the roof  30  is assembled to the panels  24 . Each side fascia  356  also includes three recessed connector slots  56  as in the side panels  24  to receive bolts  44  and washers  55 . 
     For structural support, the lateral roof surfaces  354  are formed to define five upwardly projecting lateral ribs  380  extending from the peak  350  to the side fascia  356 . The first and last ribs  380  are located at each lateral end of the peak  350  and the remaining three ribs  380  are spaced evenly between them so to define four rectangular panels  382 . Generally rectangular openings  384  are cut out of the center two rectangular surfaces  382  to define a pair of skylights  386  in each lateral roof surface  354 . 
     Each set of skylights  386  are covered by a translucent cover  388  having a planar surface  390  and lateral  392  and transverse  394  side walls. The transverse side walls  394  include three notches  396  sized to fit over the three central ribs  380  of the roof  30 . The covers  388  also has a tabbed edge  398  having two transverse tabs  400  sized to snugly fit within transverse slits  402  cut into the longitudinal surfaces  352  of the peak  350 . The tabs  400  have tapered corners  404  to aid in inserting the tabs  400  into the slits  402 . The covers  388  are assembled to the roof  36  by inserting the tabs  400  into the slits  402  and fitting the notches  396  over the ribs  380 . Fasteners  406  placed through bores  408  in the covers  388  and the ribs  380 , respectively, secure the covers  388  in place. 
     As best shown in FIGS. 13A and 13B, rain gutters  410 , having an essentially semi-circular cross-section, are formed in the perimeter of the two central rectangular panels  382  of the roof surfaces  354 . The gutters  410  may form a U-shape around three sides of the perimeter of the central panels  382  or may be disjoined under the tab slits  402  to form opposing, inverted L-shaped gutters  410  as illustrated. In either case, the gutters  410  extend from beneath the ends of the slits  402  to the lower end of the roof  354  surfaces, so that rain can flow off the roof in the direction shown by the arrows in FIG.  13 C. Gutters  410  catch any droplets that enter beneath the cover  388  at the ends of the tabs  400 , so that they do not enter the inside of the building. 
     A cylindrical chimney  412 , with opening  413  cut out, is formed to extend longitudinally upward in one roof surface  354  near a corner created by the intersection of lateral  354  and transverse  364  roof surfaces with the side fascia  356 . The chimney  412  aligns longitudinally with the cylindrical aperture  182  of the tank  42  when the structure  20  is assembled, so that a venting pipe  415 , preferably made of a polyvinyl chloride material (shown in FIGS.  14 B- 14 D), can be connected therebetween. 
     As shown in FIGS. 7B-7D, the roof  30  is joined to the side panels  24  at three, generally rectangular, stand-offs  381  in the outer wall  61  that project outward at the upper edge of the panels  24 . The inner wall  59  is formed to define an inner stand-off recess  383  that meets the outer wall  61  at the face  385  of the stand-offs  381 . The stand-offs  381  and the inner stand-off recess  383  have a bore  387  in the face  385  for receiving the bolt  44  which is fastened to nut  58  disposed in the inner stand-off recess  383 . This structure is similar to the previously described receivers  46  for attaching the walls to the base. 
     The preferred method of assembly of the toilet embodiment of the structure  20  is shown in FIGS. 14A-14D. To assemble the structure, the base  22 , with the floor board  40  attached, is laid on a flat surface and the bolts  44  in the base  22  are backed out approximately ½″. Then, the back wall panel  24  is assembled to the back of the base  22  by placing the receivers  46  over the bolts  44 . Then, the tank  42  is placed onto the base framework  38  with the top  122  and bottom  124  of the tank connected together. The tank  42  is tilted backward slightly so that the tabs  120  can be fit within the slots  118  in the T-projection  106  of the rear wall  24 , at which point the tank  42  is set in place and the bolts  44  are tightened to hold the rear wall  24  in place. Then, the side walls  24  are assembled by fitting the tank tabs  42  in the T-projection slots  118  and the receivers at the bottom of the panels over the bolts  44 , which are then tightened. The flanged edges  88  of the two rear corners of the side panels  24  are joined together by sliding the corners  50  within the edge channels  82 . The front panel  26 , with the door  28  hinged thereto, is assembled to the base by resting the bottom of the panel on the feet  32  of the base  22  and screwing the threaded fasteners  49  through the bottom of the panel and into the base  22 . The flanged edges  88  of the side  24  and door frame  26  panels then are joined together by sliding the corners  50  within the edge channels  82 . And, bolts  91  are disposed in the cross-drilled bores  93  and  101  and tightened to nut  95  so as to secure the panels  24  to the base  22 . The roof  30  is set on top of the assembled panels  24 ,  26  and the bolts  44  are inserted through fitting slots  56  fit and the bolts  44  are tightened. Finally, the venting pipe  415  is then inserted into the cylindrical aperture  182  in the tank top  122 . 
     As shown in FIGS. 15A and 15B, in an alternate embodiment, the building  20  can be used as a bus stop shelter  414 . The structure  20 , in this embodiment, has a base  22 , side panels  24 , door frame panel  26 , door  28  and roof  30 . The side panels  24 , having the inner surface T-projections  106 , are joined to the base  22  by bolts  44  through slots  46 . The panels  24 ,  26  have edge flanges  52 , which are joined by corners  50 . The door  28  and door frame  26  are formed in a one-piece panel  198 , from which waste material  208  is cut out to define the living hinge  206  and separate the door portion  200  from the door frame portions  202 ,  204 . The door  28  is pivotally hinged to the door frame panel  26  and biased closed by the door tensioning mechanism  332 . The door  28  is opened by handle  254  from the outside and locked on the inside by latch  266 . In this embodiment, the outdoor structure  20  is constructed and assembled in the same manner as the toilet embodiment described above except: it includes windows  416 ,  418  and  420  in the sides panels  24  and the door  28 ; the tank  42  is replaced by a bench  422 ; the occupancy window  268  is not cut out of the door  28 ; the opening  413  is not cut out of the chimney  412 ; and there is no decal  270  on the latch  266 . 
     Generally, the bench  422  is formed in a U-shape to fit against the three side panels  24 . The bench  422  has an inverted U-shape cross-section having a seat  424 , sides  426  and ends  428 , which can be nested within other bench seats. The bench  422  has notches  430  at the outer perimeter to accommodate the stem  108  of the projection  106 . Two legs  432 , preferably made of a plastic wood material, are fastened to the inside surface  434  of the side walls  426  at the inner corners  436  of the bench  422 . The legs  432  are sized so that the seat  424  fits under the cross-bar  110  of the T-projection  106 , i.e., approximately the same height as the tank  42 . The legs  432  rest on a larger floor board  40  that covers the framework  38  of the base  22 . Fasteners  433  secure the bench  422  to the side  24  and door  26  panels at various places. 
     As stated, the bus stop shelter  414  also includes side panel windows  416  or  418  and door window  420 , made of transparent plastic sheets. FIG. 15A illustrates the bus stop shelter  414  with the smaller side windows  416  within frame  64 . FIG. 15B shows the larger side windows  418  where the outer walls  61  of the side panels define a large window frame  438  with muntins  439  so as to resemble four-pane windows. The door window  420  is placed where the gender sign  68  and business card  70  frames were located in the toilet embodiment. Openings  440  are cut through the inner  59  and outer  61  walls of the side panels  24  and the door  28 . A slit (not shown) is cut into the inner walls  59  below the openings  440  so that the plastic sheet windows may be slid between the walls  59  and  61  and over the openings  440 . As shown in FIGS. 15E and 15F, the windows  416  rest on a ledge  442  formed by the union of the inner  59  and outer  61  walls, and although not shown, the large side windows  418  and the door window  420  rest on a similar ledge. The windows  416 ,  418  and  420  are secured in place by a fastener  444  at the bottom center of the windows which is threaded through the walls  59  and  61  and the windows and into an acorn nut  446 . 
     The present invention may include other aspects not specifically delineated in the aforementioned preferred embodiments. As such, this description in no way is intended to limit the scope of the invention. For example, many of the aforementioned benefits of the present invention apply to buildings with side panels of single-sheet construction. In such construction, since there is only one layer or wall of plastic, the interior and exterior surfaces are the same. Thus, if the exterior of the building was molded to resemble brick or siding, the interior surface would also resemble brick or siding. This is not only aesthetically displeasing, but the recesses and corners forming the desired exterior surface make the interior surface difficult to clean, which is especially undesirable for the outhouse embodiment. Preferably, therefore, the interior surface would be smooth and flat which would resemble an interior wall of a home and be much easier to clean. 
     Accordingly, buildings made of single-sheet construction may include an insert liner (not shown). The liner is formed of a single sheet of plastic resin of the proper dimension to cover the exposed interior surface of the side panels. The liner can run the full length of the side panels and be trimmed to fit around the tank, or the tank may be removed and reassembled after the liner is inserted. Alternatively, the liner may be sized to cover only the portion of the side panels extending from the top of the tank to the top of the side panels. Either way, the longitudinal edges of the liner are fit into seamed corners of the door panel and side panel connections. The liner may be a non-molded sheet that is rolled up for shipping. The liner sheet may have longitudinal grooves disposed in the sheet at the locations where the rear corners of the building are located to facilitate bending of the liner and to create tight radius corners. The liner may also be thermoformed to define hinged corners corresponding to the rear corners of the building such that the liner may be folded upon itself as three sections. In either case, the liner provides a smooth aesthetically pleasing surface that is easy to assemble and clean. 
     Furthermore, the side and door panels may also be joined by the alternative corner connectors  500  shown in FIG.  16 A. In this embodiment the side panels  502  have side flanges  504  similar to flanges  88  described above and shown in FIG. 6C, however, without the interlocking projections and receivers. Also the longitudinal tubular members  86  defining channels  82  (shown in FIGS. 6B and 6C) may be removed. The corner connectors  500  (one shown) have two grooves  506  for receiving the flanges  504  which define outer walls  508  and a central Y-shaped stem  510 . To assemble, the corner connectors  500  are slid over the flanges  504  of two adjacent side or door panels  502  such that the central stem  510  is between the two flanges  504  and the flanges  504  are disposed in the grooves  506 . A head  512  of the Y-stem  510  forms a right angle such that outer edges of the head  512  contact the inner surface of the side panels  502  and urge the flanges  504  into the grooves  506  of the corner connectors  500 . 
     A variation of the embodiment in FIG. 16A is shown in FIG.  16 B. In this embodiment, the side panels  550  have flanges  552 . Corner connectors  554  (one shown) have outer walls  556  and an central stem  558  defining two grooves  560  for receiving the flanges  552 . The stem  558  has an M-shaped head  562  mating with corresponding angled surfaces  564  and  566  of the side panels  550 . In this way, the head  562  of the stem  558  urges the side panel flanges,  552  into the grooves  560  of the corner connectors  554 . 
     In still another alternate corner connection embodiment, shown in FIG. 16C, side panels may be molded joined together as a single large panel  600  with an inner wall  602  formed to include two longitudinal living hinges  604  (one shown) at the location of the rear corners of the building. The outer wall  606  forms an aesthetically pleasing corner which conceals the inner wall living hinges  604 . Prior to assembly,  10  the internal side walls lie in the same plane and the living hinges  604  are in an open position. For assembly, the single large panel  600  is folded or flexed inward at the living hinges  604  to form three sides at right angles. As shown in FIG. 16C, when assembled, the living hinges  604  are in a closed position and the corner  608  of the outer wall generally forms a right angle. Longitudinal channels  610  are disposed in the outer wall  606  for structural support. 
     Accordingly, in order to apprise the public of the full scope of the present invention, reference must be made to the following claims.