Patent Publication Number: US-2004045229-A1

Title: Buiding guide strip

Description:
TECHNICAL FIELD  
       [0001] The present invention relates to building and, in particular, to the application of cement, plaster, texture coatings or other renders around window frames and like fittings in a building, and to the installation of cornices and like decorative fittings within a building.  
       BACKGROUND  
       [0002] In many buildings the support columns or walls adjacent window frames are formed from brickwork, concrete or similar masonry structures which are load bearing. In order to position a window at its intended location, a timber or aluminum window frame is secured to the masonry. To provide an ascetically pleasing finished appearance, the masonry is then rendered with cement, plaster or the like so as to form a smooth layer of render which hides any irregularities in the masonry. This layer should smoothly abut the window frame. However, the action of smoothing the render often results in render being applied to the window frame itself and/or the window frame being scratched by the tool used in the smoothing process. Furthermore, it is not unknown for some unscrupulous sub-contractors to provide a very thin rendered layer which subsequently breaks because it is insufficiently strong.  
       [0003] In addition to the rendering process described above being time-consuming and requiring relatively highly skilled, and therefore relatively well paid, tradesmen, there is often a very substantial cleanup required after the render has been applied. For example, render which has adhered to the window frame or window must be removed from the window frame or window. This often results in the window frame being scratched. Such scratches, or other scratches during the application of the render, often require the window frame to be touched up or repainted.  
       [0004] Furthermore, the render itself is normally painted once it is dried and this requires either great care on the part of the painter so as not to inadvertently apply paint to the window frame, or considerable time must be spent in masking the window frame prior to the application of the paint.  
       OBJECTS OF THE INVENTION  
       [0005] It is the object of the present invention to seek to reduce, or at least ameliorate, the abovementioned disadvantages by the provision of both a guide strip to assist in cement rendering around window frames and like openings, and also the provision of a method of cement rendering around window frames and like openings of a building.  
       [0006] It is a further object of the present invention to assist in and reduce the time required for the installation of cornices and like decorative fittings in a building.  
       SUMMARY OF INVENTION  
       [0007] In accordance with a first aspect of the present invention there is disclosed a guide strip to assist in cement rendering around window frames and like openings, said strip comprising two longitudinally extending portions joined in side-by-side relationship by a frangible part, one of said portions comprising a base strip to be left in-situ within said render and having a render depth setting lip extending from one side thereof alongside said frangible part, the other of said portions comprising a window frame masking portion, and said strip including connection means to secure said base strip to said frame prior to rendering.  
       [0008] If desired, the masking portion can include a length of pliant sheet which can be temporarily adhered to the window of the window frame.  
       [0009] In accordance with a second aspect of the present invention there is disclosed a method of cement rendering around window frames and like openings of a building having a wall to which said frame is secured; said method comprising the steps of:  
       [0010] (a) securing the above defined guide strip to the frame with the depth setting lip extending away from the frame,  
       [0011] (b) applying render to the wall adjacent the guide strip,  
       [0012] (c) smoothing said render to be flush with the depth setting lip, and  
       [0013] (d) breaking the frangible part to remove the masking portion of the guide.  
       [0014] Preferably, where the pliant sheet is also provided, it is removed simultaneously with the masking portion.  
       [0015] In accordance with a third aspect of the present invention there is disclosed a method of installing cornices, particularly between a ceiling and a wall formed from face bricks, timber panels or the like, said method including the steps of:  
       [0016] (a) securing the above defined guide strip to said wall with the depth setting lip extending away from said wall and at a location on said wall that allows said lip to abut said cornice once said cornice is secured,  
       [0017] (b) applying cornice fixing material either to said cornice or to regions on said ceiling and the base strip of said guide strip to which said cornice is to be adhered,  
       [0018] (c) securing said cornice to said ceiling and said base strip such that said cornice abuts said lip of said guide strip,  
       [0019] (d) removing excess cornice fixing material from said ceiling and said guide strip, and  
       [0020] (e) breaking the frangible part to remove the masking portion of the guide. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0021] Several embodiments of the present invention will now be described with reference to the drawings in which:  
     [0022]FIG. 1 is a transverse cross-sectional view of the guide strip of the first embodiment of the present invention;  
     [0023]FIG. 2 is a perspective view of the strip of FIG. 1,  
     [0024]FIG. 3 is a schematic perspective view of the guide strip of FIGS. 1 and 2 with the masking portion in the process of being broken away from the base strip,  
     [0025]FIG. 4 is a schematic perspective view illustrating a masonry column to which a window frame is secured, the guide strip of FIGS.  1 - 3  being secured to the window frame,  
     [0026]FIG. 5 is a view similar to FIG. 4 but illustrating the rendering process,  
     [0027]FIG. 6 is a view similar to FIG. 5 but illustrating the masking portion being broken away following completion of the rendering and painting,  
     [0028]FIG. 7 is a view similar to FIG. 1 but illustrating a guide strip of a second embodiment,  
     [0029] FIGS.  8 A-C are transverse cross-sectional views of a guide strip of a third embodiment showing the mechanism by which the guide strip attaches to a L-shaped skirting of a window frame,  
     [0030]FIG. 9A is a view similar to FIGS.  8 A-C but illustrating the guide strip of the third embodiment once attached to an elongated block type skirting of a window frame,  
     [0031]FIG. 9B is a view similar to FIG. 9A but showing the guide strip of the third embodiment once attached to a semi-circular type skirting of a window frame,  
     [0032]FIG. 10 is a view similar to FIG. 1 but illustrating a guide strip of a fourth embodiment,  
     [0033]FIG. 11 is a view similar to FIG. 4 but illustrating a guide strip of the fifth embodiment,  
     [0034]FIG. 12 is a perspective view from the front of a guide strip of a sixth embodiment,  
     [0035]FIG. 13 is a rear perspective view of the guide strip of FIG. 10,  
     [0036]FIG. 14 is a side elevation of the guide strip of FIGS. 12 and 13,  
     [0037]FIG. 15 is a perspective view showing the use of the strip of FIGS.  12 - 14 ,  
     [0038]FIG. 16 is a view similar to FIG. 1 but of a guide strip of a seventh embodiment,  
     [0039]FIGS. 17 and 18 are each horizontal cross sections showing an installation including the strip of FIG. 16 after rendering, and  
     [0040] FIGS.  19 - 21  are each an end elevation showing the application of the strip of FIG. 1 in relation to cornices. 
    
    
     MODES OF CARRYING OUT THE INVENTION  
     [0041] As seen in FIGS.  1 - 3 , the guide strip  1  of the first embodiment is preferably extruded from plastics material and takes the form of a base strip  2  and a window frame masking strip  3  which are arranged longitudinally in side-by-side relationship and joined by a frangible part  4 .  
     [0042] The base strip  2  is provided with a rendered depth-setting lip  6  which has an outer surface  7  flush with the frangible part  4 . The base strip  2  also has a longitudinally extending groove  8  which assists in keying the base strip  2  and the render together. Additionally, the groove  8  can be scored with a knife and the base strip longitudinally snapped. This narrows the base strip  2  for use in those circumstances where a thinner render depth is required. Alteratively, the base strip  2  can be fabricated in different sizes.  
     [0043] On the other side of the base strip  2  from the lip  6  is positioned a ribbon  9  of double-sided adhesive. One side of the ribbon  9  adheres to the base strip  2  and, as best seen in FIG. 4, the other side of the ribbon  9  is used to adhere the guide strip  1  to a window frame  12  which has been secured to a masonry column, wall or similar structure  13 . As seen in FIG. 4 the guide strip  1  is adhered to the window frame  12  so that the edge of the base strip  2  remote from the masking strip  3  is substantially flush with the masonry  13 . In situatio is where some movement is anticipated (eg high rise buildings), the ribbon  9  can include foam, rubber and like substances. Then the window can give slightly relative to the masonry.  
     [0044] Thereafter, as best seen in FIG. 5 a layer of cement, plaster or similar render  15  is applied to the masonry  13  and smoothed using an adjustable set square  16 . As seen in FIG. 5, the set square  16  utilises the outer surface  7  of the lip  6  as a guide. This guide results in two aims being simultaneously achieved. Firstly, the depth of the render  15  is determined by the distance between the outer surface  7  of the lip  6  and the masonry  13 . Thus, this distance can be assured to be at least a minimum distance, typically 10 mm. In addition, the end of the set square  16  is moved over the surface of the masking strip  3  so that the set square  16  does not come into contact with, and thereby scratch, the window frame  12 . As schematically illustrated in FIG. 5, a wooden trowel can, if desired, be used to provide a desired surface finish on the render  15 . Again, the trowel  18  can use the outer surface  7  of the lip  6  and the masking strip  3  as guiding surfaces.  
     [0045] After the final condition of the render  15  has been achieved, the render  15  is allowed to set and can then, if desired, be painted to suit the final intended decor of the interior of the building. During the painting procedure, the masking strip  3  prevents any paint from being inadvertently placed on the window frame  12 . Once the paint has dried, as schematically illustrated in FIG. 6 the masking strip  3  can be broken away from the base strip  2  by rupturing the frangible part  4 . This leaves the base strip  2  embedded against the masonry  13  by the render  15  with only the outer surface  7  of the lip  6  and the broken edge of the frangible part  4  being visible. This portion of the lip  6  forms a narrow bead which provides a high definition boundary between a window frame  12  and the render  15 . Depending upon the colour used in the fabrication of the guide strip  1  and the colours of the window frame  12  and paint used to cover the render  15 , the visible portion of the lip  6  can constitute either a high contrast boundary or an inconspicuous edge to the render  15 . The embedded base strip  2  also acts as a permanent barrier between the window frame  12  and the render and thereby inhibits the corrosion of metallic window frames that can otherwise gradually occur after render has set in direct contact with metallic window frames.  
     [0046]FIG. 7 illustrates in cross-section alternative guide strip  21  of a second embodiment in which like portions relative to the guide strip  1  of FIGS.  1 - 3  are marked with like numerals. The main difference between the guide strip  21  of FIG. 7 and the guide strip  1  of FIG. 1 is that the double-sided adhesive ribbon  19  is not used and instead a U-shaped flange  23  is provided. The U-shaped flange  23  opens towards that side of the base strip  2  opposite the lip  6 . The U-shaped flange  23  enables the guide strip  21  to be pressed onto the aluminum window frame  12  and held thereon by means of a friction fit. Thus the double-sided adhesive ribbon  9  is not required. This results in a stronger keying action between the render and the base strip  2 .  
     [0047] However, as many aluminum window frames are often bordered by skirting extending around the outside and inside edges of the window frame, the U-shaped flange  23  may not be of a size and shape that facilitates a secure friction fit. A further alternative guide strip  31  of a third embodiment is shown in FIGS.  8 A-C and is adapted to ensure a secure connection between the guide strip  31  and a window frame  12  having an inwardly projecting L-shaped skirting  25  extending around the outside edge  26  of the window frame  12 . This third embodiment depicted in FIGS.  8 A-C, as with all subsequent embodiments described below, is again numbered such that like portions relative to the guide strip  1  of FIGS.  1 - 3  are marked with like numerals. To replace the U-shaped flange  23  of the first embodiment, the guide strip  31  is provided with a resilient D-shaped flange  27  terminating with a foot  28  that projects away and is acutely angled to the base strip  2 . The mouth region  29  of the D-shaped flange  27  is narrower than the width of the skirting  25 .  
     [0048] Once the guide strip  31  is positioned against the window frame  12  as seen in FIG. 8A, the leading face  30  of the foot  28  of the untensioned D-shaped flange  27  is pressed against the skirting  25 . When the skirting  25  is run along the leading face  30  and pushed past the narrowest portion of the mouth region  29  of the D-shaped flange  27  as illustrated in FIG. 8B, the skirting  25  is captured within the flange  27  and presses against the roof portion  32  of the flange  27  to firmly secure the guide strip  31  to the window frame  12  as seen in FIG. 8C.  
     [0049]FIG. 9A illustrates that the guide strip  31  can still attach to a window frame  12  bordered by a skirting  35  having a more elongated shape in cross-section by the inner edge  33  that begins the leading face  30  of the foot  28  pressing against the skirting  35 . In FIG. 9A, there are two points of contact between the D-shaped flange  27  and the skirting  25 . However, the force exerted by the tensioned D-shaped flange  27  at its inner edge  33  on the surface of the semicircular type skirting  45  of the window frame  12  as illustrated in FIG. 9B is sufficient to secure the guide strip  31  to the window frame  12  without the need for a second point of contact between the flange  27  and the frame  12 .  
     [0050] The D-shaped flange  27  of the guide strip  31  can be secured to a window frame  12  having a skirting of any shape or size provided that the skirting is not so wide that the flange  27  cannot be stretched so that the edge  33  of the flange  27  presses against the skirting  45 . Similarly, the particular profile of the flange used to secure any of the above described guide strips to the window frame  12  need not be U-shaped or D-shaped, but instead can be any shape that ensures a secure attachment of the particular guide strip to the frame  12 . Further, the flange can be moulded to suit the specific contour exhibited by many commonly shaped skirtings found on window frames to provide a better friction engagement.  
     [0051] A fourth embodiment of a guide strip  36  is shown in FIG. 10 which differs from the strip  1  of the first embodiment in that the longitudinally extending groove  8  is replaced with a kink  24 . The kink  24  is more effective in keying together the base strip  2  and the render once set since the base strip  2  of the guide strip  41  presents a larger surface area available for contact with the render.  
     [0052] Turning now to FIG. 11, here a wooden window frame  42  is provided with a vertically extending groove  43 . The guide strip  41  is provided with a barbed protrusion  44  which is received in the groove  43  as a friction fit to retain the strip  41  relative to the frame  42 . The remainder of the strip  41  functions as before.  
     [0053] A still further embodiment in the form of strip  51  is illustrated in FIGS.  12 - 15 . The strip  51  is essentially as illustrated in FIG. 10 but is provided with a length of pliant sheet  52  which is preferably of the same length as the strip  51  and of any suitable width. The sheet  52  is preferably formed from flexible PVC sheeting which is inexpensive. The sheet  52  is adhered or otherwise attached to the masking strip  3 . Ultrasonic welding, other fusing techniques, double sided adhesive strips, or glues are able to be used. The sheet  52  functions as an extension of the masking strip  3  and is preferably held against the glass  53  of the window frame  12  by means of adhesive tape  54 .  
     [0054] The effect of the sheet  52  is to entirely cover the window frame  12  and an adjacent peripheral region of the glass  53  from all splashes of render, paint etc, and all damage from inadvertent scratching or damage from the tools of workers of all trades on a building site. After all actions such as rendering and painting have been completed, the masking strip  3  can be detached from the strip  51  and the sheet  52  simultaneously detached from the glass  53 . Thus a neat finish is created.  
     [0055] As illustrated in FIGS.  16 - 18 , the base strip  2  can be modified to enable firstly the width of the base strip  2  to be adjusted. As seen in FIG. 16, the adjustment preferably takes the form of three longitudinally extending grooves  61 . One of the grooves  61  can be scored with a knife and the base strip  2  longitudinally split to a desired width.  
     [0056] Secondly, the base strip  2  can be bent into various configurations as illustrated in FIGS. 17 and 18 in order to bridge any gap between the window frame  12  and masonry  13 . This assists in the rendering process by eliminating the need to insert a filler such as paper previously required to avoid render penetrating the wall cavity  60 .  
     [0057] Turning now to FIGS.  19 - 21 , the building strip also finds application in the fixing of cornices. Where cornices are installed between a plasterboard wall and ceiling, any excess in the material used to secure the cornice to the plasterboard is easily scraped from the plasterboard before the material has set.  
     [0058] However, where the wall is formed from face bricks, timber panels and the like, removal of the excess material is an extremely difficult job—particularly if the wall material is somewhat porous.  
     [0059] As indicated in FIG. 19, this cornice adhering material  65  is located along each edge of a cornice  66 . A guide strip  1  is located on the wall  67  at a predetermined distance below the ceiling  68 . Then the cornice  66  is installed resulting in excess material  65  being deposited on both the ceiling  68  and the guide strip  1  as indicated in FIG. 20.  
     [0060] As indicated in FIG. 21, the excess material  65  can be cleaned off the ceiling  68  and the strip  1 . Then the masking strip  3  can be broken away from the remainder of the strip  1  to leave a smooth clean edge and an unobtrusive addition to the lower edge of the cornice  66 .  
     [0061] The right hand portion of FIG. 21 illustrates the use of the guide strip  1  in relation to a timber wall panel or timber feature frieze  69 , or the like.  
     [0062] The foregoing describes only some embodiments of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention For example, although the guide strip of the various embodiments described above finds particular application to the sides of window frames, the invention is also applicable to the frames of prefabricated doors. The invention is particularly useful with texture finishes which have required window frames, etc. to be masked a first time, the finish applied, the first masking removed and then a second masking applied to permit the set finish to be painted. With the present guide strip, both masking tasks are eliminated.  
     [0063] The term “comprising” as used herein is used in the inclusive sense of “having” or “including” and not in the exclusive sense of “consisting only of”.