Abstract:
A system for attaching architectural molding or insulation sheets to buildings or other structures which uses headed fasteners that bear against strips of substantially rigid material embedded in the molding or sheets that include a foam plastic core optionally covered with a hard base coat of cementitious material.

Description:
This application claims the benefit of U.S. provisional application Ser. No. 60/086,685, filed May 22, 1998. 
    
    
     This invention relates to a system for attaching architectural molding or insulation sheets to buildings, and more particularly to attaching architectural moldings formed from a light foam plastic core covered with a hard base coat or insulation sheets of light foam plastic to an exterior substrate or wall of a building or structure using fasteners that bear against an insert or strip that extends through the moldings or sheets. 
     BACKGROUND OF THE INVENTION 
     Within the last few years, the use of light-weight prefabricated architectural moldings or shapes for application to the exterior walls of buildings has increased. Such moldings are used to enhance the aesthetic beauty of a surface area. These moldings are constructed of a light-weight plastic material covered by a hard protective base coat. A finish coat also is usually applied over the base coat once they are attached to a wall or substrate of the building structures. 
     Heretofore, in order to secure the molding to the structures, the shapes were adhesively attached to the substrates or walls of the structures. However, moisture often accumulated between the moldings and the substrate, thereby eroding the adhesive and causing separation of the molding from the substrate. Where it would be desired to apply the molding to a wall of a building covered with a moisture barrier type plastic sheeting, various fasteners thus were employed. 
     One type of fastener is a nail or screw with a large plastic washer. The large plastic washer is designed to be pressed into the molding until it is at least slightly below the surface so the opening created in the base coat can be filled, thereby creating a generally flat outer surface. However, the large size of the washers and hardness of the coating on the moldings often caused the coating to crack, thereby requiring repair or replacement. Furthermore, because of the large area necessary to be recoated due to the size and effect of the washer, variations in shading sometimes were present on the moldings after the finish coat was applied. 
     It has also been known to use adhesives or washers and screws, separately or in combination, to attach insulation sheets to buildings. Installing insulation sheets, which usually are 2 feet by 4 feet sheets, with such fastening systems often led to the same or similar problems as encountered in the mounting of moldings as above mentioned. 
     SUMMARY OF THE INVENTION 
     The present invention overcomes the problems in securing architectural molding to substrates on structures or insulation sheets to buildings. The molding of the present invention includes a core of light plastic material covered by a skin of hard, preferably cementitious, material. A fastening strip of substantially rigid material is embedded within the core of light plastic material. To mount the molding onto the substrate of the structure, the molding is placed against the structure in the desired location. Then, fasteners, such as drywall screws, are inserted completely through the hard skin or base coat into the core and through the strip in the core of the molding and into the substrate of the structure until the heads of the screws abut and press against the strip. If desired, prior to fastening, a small hole formed through the skin and into the core can be made by a drill or other device for facilitating the use of fasteners. 
     The use of fasteners such as screws allows the molding to be securely attached to the substrate of the structures. Furthermore, using fasteners with pointed ends allows for the screw to penetrate the hard base coat or skin and the molding by forming a small hole in the skin and core to the strip and without causing appreciable damage to the base coat or molding. Thereafter, the small holes can be filled very easily with a suitable material. 
     Similarly, insulation sheets of the present invention include at least one fastening strip of substantially rigid material embedded within the sheet. The sheets are then mounted onto a building by inserting fasteners through the sheets and strip and into the building. The strips may be sized and arranged to interlock adjacent sheets. 
     It is therefore an object of the present invention to provide architectural molding and insulation sheets that may be easily and securely attached to substrates of structures and/or buildings. 
     Another object of the invention is to provide for attaching architectural molding without causing appreciable damage to the base coat or skin of the molding or the molding itself. 
     A further object of the invention is to provide for attaching insulation sheets without causing appreciable damage to the sheets. 
     Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheet of drawings, wherein like reference numerals refer to like parts. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of one variation in shape of architectural molding of the present invention; 
     FIG. 2 is a vertical plan side view of the same variation of architectural molding of the present invention; 
     FIG. 3 is a cross-sectional view of the same variation of architectural molding of the present invention fastened to a wall or substrate of a structure; 
     FIG. 4 is a vertical plan view of the same variation of architectural molding of the present invention fastened around a window; 
     FIG. 5 is an isometric view of another embodiment of architectural molding of the present invention with the strip partially inserted into the molding; 
     FIG. 6 is a perspective view of a sheet of insulation formed with channels for receiving fastening strips; and 
     FIG. 7 is an elevational view of a plurality of sheets of material and fastening strips with some parts broken away to show underlying parts. 
    
    
     DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, FIGS. 1 to  4  show one design shape for the architectural molding of the present invention, generally indicated by the numeral  10 . The molding  10  includes a core of light-weight plastic material  12  with a base wall, an outer formed face, a slot or channel  20 , a reinforcing mesh  14 , and a base coat  16 . The plastic material  12  is preferably any suitable foam plastic (sometimes called cellular plastic) having light-weight and good strength characteristics, such as foam polystyrene or Styrofoam plastic having a desired rigidity, but may be any other type of suitable light-weight plastic material. Styrofoam is a trademark of Dow Chemical Co., and constitutes an expanded cellular polystyrene. The desired shape of the plastic material  12  may be prefabricated or it may be formed by cutting the shape from a foam plastic block. A mesh  14  is located on top of the desired shape of the plastic material  12  to reinforce the base coat  16 . Preferably, the mesh  14  is a 4.5 ounce standard fiberglass woven mesh. The base coat  16  which is applied over and to embed the mesh  14  is comprised of a suitable cementitious material, such as a hydraulic cement, which when cured forms a hard outer surface for the molding to protect the molding  10  from outside elements, for example, moisture, and which may receive any suitable finish coat. 
     As shown in FIGS. 1 to  3 , a slot or channel  20  is formed inside the core of the plastic material  12 . The slot  20  may be formed by moving an L-shaped hot wire through the plastic material  12  before applying the base coat  16 , or it may be formed by any other suitable means, such as molding or cutting. A hot wire (not shown) passed through the length of the molding  10  forms an L-shaped channel or slot  20  in the molding  10 . The mesh  14  and base coat  16  may then be applied over the plastic material  12  to seal off the top end of the slot  20 . 
     Once the slot  20  is formed, a strip of rigid material  22  is then inserted into the slot  20 . The size of the slot may be such that the strip may be easily inserted. The strip  22  is preferably a polyurethane, or polycarbonate resinous material such as that marketed under the trademark Lexan, but may be made of any suitably rigid material, such as wood, metal or other plastic. Lexan is a trademark owned by General Electric Corporation. 
     In application, the molding  10  is placed into its desired location against a suitable substrate or wall. While the molding  10  in FIG. 4 is shown placed on the exterior wall of a building around a window  50 , it should be appreciated that the molding  10  may be used in numerous places, including around doors, on columns or facia, both exteriorly and interiorly. The molding  10  may be initially held in its desired place by hand or other means, such as an adhesive. Once the molding  10  is in its desired place, a plurality of fasteners, such as drywall screws  34  are inserted into the molding  10 . Such screws generally include a beveled head and a threaded shank. In terms of a screw  34 , the screw is placed on the molding in alignment with the strip  22  such that it will pass through the strip  22  and into the substrate of the structure  32 . In order to facilitate the proper placement and positioning of the screw before it is driven through the molding, a line or other suitable marking or indicia may be used on the top of the base coat  16  of the molding  10  such as a dashed line  23  shown in FIG.  1 . The screw  34  may be inserted until the beveled head of the screw  34  contacts and bears tightly against the strip  22  in the core of the plastic material  12 . The molding  10  will then be securely fastened to the substrate of the structure  32 . 
     Although the length of the strip  22  can vary, the strip preferably should be sized to extend substantially the full length of the molding. The strip should also be of sufficient width to allow for the fasteners  34  to have sufficient area to pass through the interior section of the strip  22  and also to define the appropriate bearing contact with the foam plastic core  12 . It is also desired that the strip  22  has a sufficient width to press against a sufficiently broad part of the plastic core material  12  of the shape or molding  10  when the fastener  34  contacts or bears against the strip  22  to prevent the strip from penetrating the core material or moving through the material, whereby the molding  10  will be securely fastened to the substrate of the structure  32 . For example, it is known that a strip  22  having a width of about one inch (2.54 cm) and a thickness of about one-eighth inch (3.5 mm) may be used on the molding  10  shown in FIGS. 1 to  4  having a width of about nine inches (22.86 cm). 
     As shown in FIG.  3  and FIG. 4, small holes  40  will be formed in the base coat  16  and the upper portion of the plastic material  12  where the screw  34  has passed. The holes  40  may be filled with cementitious material or other suitable material such as caulking, and smoothed as shown at  56  on the section of molding  10  on the left-hand side  52  of the window  50  in FIG.  4 . If desired, a finish coat may then be applied over the base coat  16 , or over the holes  40  themselves, to form a uniform surface, as shown at  58  below the bottom part  54  of the window  50  in FIG. 4. A suitable finish coat is preferably an acrylic-based material with a stone aggregate, but may be any other suitable type of finish coat. The finish coat, which may be up to one-quarter inch thick, may be applied by spraying or troweling the material onto the base coat, and then allowed to cure. 
     Another architectural design shape for a molding, generally indicated by the numeral  60  is shown in FIG.  5 . This embodiment also more clearly demonstrates the insertion of the strip  22  into the core of the molding  10 . It should be appreciated that this invention may be used with any of the numerous shapes of architectural moldings or other designs such as desired on imitation stucco surfaces. 
     It should also be appreciated that the system of attaching a molded foam plastic trim piece to a structure may also be used without providing the trim piece with an outer hard base coating. Such a base coat of cementitious material, along with any finish coat or coats may be applied at the building site. The attaching system of the present invention is an improved system over the prior art systems identified in the Background of the Invention. 
     Referring now to FIGS. 6 and 7, insulation sheets  70  or panels utilizing the attaching system of the invention are shown. The insulation sheets  70  are generally made of a suitable foam plastic, such as Styrofoam plastic. The system includes the formation in each sheet  70  of a plurality of longitudinally extending slots or channels  72  and/or U-shaped channels  74 . The slots may be formed using a hot wire, or using any other suitable means, such as molding or cutting. The slots or channels  72  extend longitudinally through the central area of a sheet, while U-shaped channels  74  forming about one-half of a full channel may be formed on the edges of the sheets  70  so that a complete slot may be formed where another sheet with a similar but opposing U-shaped channel  74  is placed on top of the edge of the sheet, as shown in FIG.  7 . 
     Once the slot is formed, strips like those in FIGS. 3 and 4 may be inserted into each of the slots  72  and the edge channels  74 . The strips  80   a ,  80   b  and  80   c  may also be of such a length to extend entirely through one sheet and into one or more adjacent sheets of material. Thus, adjacent sheets may be interconnected or interlocked to one another. Furthermore, the channels  74  on the edges of the sheets  70  serve to receive a fastening strip  80   a ,  80   b  and  80   c  to interconnect or interlock the adjacent sheets together along their longitudinal edges. 
     It should be appreciated that any number of channels may be provided in a sheet, and that the edge channels may be omitted. Further, the channels may extend horizontally or vertically, but preferably parallel to an edge of the sheet. 
     To secure the insulation sheet  70  to a building, the sheet  70  is first placed against the building in its desired location. The sheet  70  may be held in place by hand or by other means, such as using adhesive. Once in place, a plurality of fasteners such as screws are inserted into the sheet  70  such that they will pass through the strip  68  and into the building. Lines or other marking or indicia means may be used to facilitate the proper placement of the screws. The screws are then driven into the substrate or wall on which the sheets are mounted until the screw heads engage and press against the fastening strips. The holes formed by the screws may be filled with a suitable material if desired. After the insulation sheets are secured to the wall, a mesh and coating are generally applied to the surface of the insulation sheets. As seen in FIG. 7, a plurality of insulation sheets or panels are mounted on a wall  78  to illustrate the interlocking of adjacent sheets and provide an interlocked layer of insulation. The sheets are generally rectangular and would normally be two feet by four feet in size and of any suitable thickness. Sheets  70   a ,  70   b  and  70   c  are illustrated as being interlocked together by fastening strips  80   a ,  80   b  and  80   c . Strips  80   b  and  80   c  extend through channels in sheets  70   b  and  70   c  to interlock and align sheets  70   b  and  70   c . Strips  80   b  and  80   c  also extend beyond sheets  70   b  and  70   c  to provide an interlocking relation with other sheets that may be attached to wall  78  in adjacent relation thereto. Strip  80   a  fits in edge channels of sheets  70   a  and  70   b  to interlock the edges of the vertically arranged sheets. While sheet  70   a  is aligned with sheet  70   b , it could be appreciated they may be arranged in staggered relation. 
     From the foregoing, it can be appreciated that the invention provides an improved system of attaching foam plastic moldings or insulation sheets to walls or substrates. 
     It will be understood that modifications and variations may be affected without departing from the scope of the novel concepts of the present invention, but it is understood that this application is to be limited only by the scope of the appended claims.