Patent Publication Number: US-2005120475-A1

Title: Sill assembly for shower installations

Description:
FIELD OF THE INVENTION  
      The present invention is directed to the field of shower plumbing and construction, and more specifically to the plumbing and construction of shower sills.  
     BACKGROUND OF THE INVENTION  
      There are two major practices for the installation of shower assemblies. The first practice involves installing a pre-formed shower receptor. The pre-formed shower receptor includes a door and wall panels. The pre-formed shower receptor may be positioned against a wall, in a corner, or an alcove, or be free standing.  
      Instead of installing a pre-formed shower receptor, the second practice calls for tiling the walls and the floor creating a shower enclosure. Creating a shower enclosure in this method is much more labor intensive and time consuming to install, but are still preferred by many users. Standard construction techniques for tiled shower installations comprise the formation of a substantially solid base of lumber or ply materials. Taking the example of a three-walled alcove, a supporting base may be formed of ply and timber lining the walls up to a particular height. The front threshold or sill assembly is typically formed from several pieces of 2″×4″ solid lumber. In such an installation, columns for mounting the door and possibly panels are often mounted on the sill.  
      Typical traditional tiled shower installation methods include, once the base or threshold area have been suitably formed and the drain exit and other plumbing pre-plumbed, placing a waterproofing membrane layer (which may be a sheet blanket or liquid material) over the substructure up to a predetermined height (often governed by regulations). Over this is next provided a mortar/bedding mix often reinforced with a metal lath. At this stage, any tapering of the floor area towards the waste, and tapering of the sill&#39;s top (to drain water back into the shower receptor area) is performed. Finally, tiles are adhesively set in place over these layers. Grouting is then performed. At this stage, final installation of components such as supporting columns and doors are performed.  
      Of recent, the preferences of what consumers want in a bathroom have shifted. For instance, the typical shower installation of the past included a single shower rose (shower head) controlled by faucets or a mixing valve. Showers over bath installations were also common. At the high end of the market, additional features were included such as multiple body spray jets (typically horizontally orientated spray nozzles arranged at varying heights). While previously restricted to the high end of the market, the average consumer now wishes to have body spray jets in a shower and at a more economical price.  
      In shower assemblies using a pre-formed shower enclosure, a void is often present between a wall of the building and a wall of the preformed enclosure. This void allows the easy routing and plumbing of a series of body water jets. However, in tiled shower assemblies, this void is not present and the placement of body water jets and plumbing involves extensive work as the plumbing must be routed through the wall. This is a time consuming and expensive process. Further, since the plumbing is often put in place before the consumer has selected the shower arrangement desired, the plumbing often has to be redone to properly locate the plumbing for body water jets.  
      Thus, there exists a need for a shower assembly for tiled installations that permits the easy routing and installation of body water jets, that is reliable, easy to install, and meets the expectations of the end user.  
     SUMMARY OF THE INVENTION  
      One embodiment of a preformed shower sill frame formed in accordance with the present invention is disclosed. The preformed shower sill frame includes a first sidewall, a second sidewall, and a top wall spanning between the first and second sidewalls, the first sidewall, the second sidewall, and the top wall defining a plumbing a channel.  
      One embodiment of a shower threshold assembly formed in accordance with the present invention is disclosed. The shower threshold assembly includes a frame attachable to a support surface. The shower threshold assembly includes a plumbing channel extending longitudinally through the frame. The shower threshold assembly includes a coupling assembly coupled to the frame for releasably attaching a device to the frame.  
      One embodiment of a kit for forming a tileable shower sill formed in accordance with the present invention is disclosed. The kit includes a frame having a plumbing channel extending along a longitudinal length of the frame and having a top surface. The kit further includes a coupling assembly extendable through the top surface. The kit further includes plumbing adapted to be connected to the coupling assembly so as to be positioned within the plumbing channel between the coupling assembly and an end of the frame.  
      One method of forming a shower sill in accordance with the present invention using a preformed sill form having a plumbing channel, the preformed sill form capable of supplying water to components attached to the preformed sill form, is disclosed. The method includes passing a protruding portion of a coupling assembly through an aperture of the preformed sill form so that the protruding portion extends outward of the preformed sill form. The method also includes securing the coupling assembly to the preformed sill form and coupling plumbing passing through the plumbing channel of the preformed sill form in fluid communication with the coupling assembly and a fluid source. The method further includes attaching the preformed sill form to a supporting surface and attaching tiling upon the preformed sill form. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The foregoing aspects and many of the attendant advantages of this invention will become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:  
       FIG. 1  is a perspective view of one embodiment of a shower assembly formed in accordance with the present invention showing a plumbing system supplying water through piping disposed within a sill assembly and a pair of door support columns to supply a series of water jets coupled to the door support columns;  
       FIG. 2  is a partially exploded perspective cut away view of the sill assembly and door support column of the shower assembly of  FIG. 1 ;  
       FIG. 3  is a cross-sectional view of one of the support columns coupled to the sill assembly of the shower assembly of  FIG. 1 ;  
       FIG. 4  is an exploded perspective view of the support column and sill assembly depicted in  FIG. 3 ;  
       FIG. 5  is a perspective exploded view of a connection piece, a cam portion, and a cam sleeve of the shower assembly of  FIG. 1 ; and  
       FIG. 6  is a perspective exploded view of the connection piece of  FIG. 5 , and a protective cap and a plug used during the installation of the shower assembly of  FIG. 1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      One embodiment of a shower assembly  100  formed in accordance with the present invention is depicted in  FIGS. 1-6 . Referring to  FIG. 1 , the shower assembly  100  includes a shower enclosure  102 , a plumbing system  104 , and a sill assembly  106 . Generally described, the shower assembly  100  permits the rapid installation of a series of body water jets  108  in a shower by permitting a section of water supply piping  110  of the plumbing system  104  to pass through a cavity or plumbing channel  138  (see  FIG. 2 ) of the sill assembly  106  and through a pair of hollow support columns  112  of the enclosure  102 .  
      In light of the above general description of the shower assembly  100 , the individual components of the shower assembly  100  will now be described in greater detail. Focusing first on the shower enclosure  102 , the shower enclosure  102  includes three tiled walls  114  and a clear glass wall  116 . The clear glass wall  116  includes a pair of support members, such as a pair of hollow support columns  112  coupled to the sill assembly  106 . A shower door  120  is pivotally coupled to one of the support columns  112  by a pair of hinges  118 . The support columns  112  are hollow, having an inner passage permitting the water supply piping  110  to be plumbed therein. The water supply piping  110  is coupled in fluid communication with a series of body water jets  108  coupled to the support columns  112 . The body water jets  108  emit substantially horizontal oriented streams of water upon an occupant of the shower enclosure  102 .  
      The shower assembly  100  further includes a plumbing system  104 . The plumbing system  104  includes hot and cold supply lines  122 H and  122 C coupled in fluid communication with a mixer  124 . A pair of control valves  126  selectively control the flow of mixed hot and cold water through the water supply piping  110  to a shower head  128  and/or the body water jets  108 .  
      Referring to  FIG. 2  and focusing upon the sill assembly  106 , the sill assembly  106  includes a pre-formed sill form or frame  130 . In the illustrated embodiment, the sill form  130  has a U-shaped cross section with a pair of legs  132 A and  132 B of the sill form  130  spaced apart from one another to receive a standard piece of timber  134  fixed to (thereby becoming part of) a supporting surface, such as the floor. In the illustrated embodiment, the standard piece of timber is a 2×4, and the legs are spaced apart between about 3 and about 4 inches, with a preferred distance of about 3.5 inches.  
      The sill form  130  may be screwed to the timber  134  by a plurality of fasteners  136 . The legs  132 A and  132 B are of sufficient length such that a cavity  138  is formed above the timber  134 , the cavity  138  defined by the inner surface of the sill form  130  and the floor, i.e., timber  134 . In the illustrated embodiment, the legs are greater than about 1.5 inches in length, with a preferred distance of about 3.75 inches. The sill form  130  may be formed from any number of rigid and semi-rigid materials, a few suitable examples being metal and/or metal alloys, such as an extruded aluminum or an aluminum alloy, and plastic materials, such as a fiber reinforced cementitious material, a fiber reinforced plastic, a moldable plastic material, a plastic foam cell material, or an extrudable plastic material. The outer surface of the sill form  130  may be textured  139  to increase adhesion of a material, such as a liquid coating membrane layer  154  for waterproofing the sill form  130 .  
      The sill form  130  includes one or more apertures  140 . The apertures  140  are located at the point wherein the support columns  112  of the shower enclosure are attached to the sill assembly  106 . The apertures  140  permit water flowing in the supply piping  110  disposed in the cavity  138  of the sill form  130  to pass through a top surface  142  of the sill form  130  and into the support columns  112 . The apertures  140  may be preformed in the sill form  130  or they may be cut into the sill form  130 , such as on site during the installation process.  
      The sill form  130  may include indicia  143  for marking preferred locations for cutting the sill form  130  to length. Moreover, different installations require sill forms  130  of different lengths. In some instances, a custom length is required and the sill form  130  may require cutting at a non-standard location. In other cases, the installation may require a sill from  130  of a more standardized length. The indicia  143  may be placed at various standard sill form lengths to aid an installer in cutting the sill form  130  to a selected standard length without having to measure the sill form  130 . Alternately, the indicia  143  may be placed at predetermined intervals, such as every half inch, with measurements printed by each indicia  143  indicating the overall length of the sill form  130  at each indicia to aid the installer in cutting the sill form  130  to a selected length during custom installations.  
      The indicia  143  may be physical markings, a few examples being raised ribs or lines extending upward from the top surface  142  of the sill form  130 . For instance, a pair of ribs or lines may be spaced approximately a width of a cutting blade apart for accepting a cutting blade therebetween for both guiding the positioning of the cutting blade at the proper location and guiding the cutting blade during the actual cutting of the sill form  130 . The indicia  143  may also be physical marking which include channels or notches sunken in the top surface  142  or extending into the top surface of the sill form  130  to guide the cutting of the sill form  130 . The indicia  143  also may be visual markings, such as painted or printed lines for aiding the selection of a location to cut the sill form  130  to length.  
      Coupled to each of the apertures  140  is a coupling assembly  144 . The coupling assemblies  144  are coupled in fluid communication with the water supply piping  110  disposed in the cavity  138  of the sill form  130  and with the body water jets  108 . Each of the coupling assemblies  144  include a union  146  and a connection piece  148 .  
      Referring to  FIGS. 2, 3 , and  5 , the union  146  of the illustrated embodiment is an elbow or T connection which is connected in fluid communication with the water supply piping  110  to permit water passage from the water supply piping  110  through the coupling assemblies  144  and into the support columns  112 . A flange  150  is disposed on the union  146  to impede the coupling assembly  144  from passing through the apertures  140  and to aid in the mounting of the coupling assembly  144  to the sill form  130 .  
      The connection piece  148  extends up from the union  146  and passes through the aperture  140 . A securing nut  152  is associated with each connection piece  148 . During transit, the nut  152  is removed or threaded on the connection piece  148  within the cavity of the sill form  130  so that at least a portion if not all of the connection piece  148  and substantially all of the associated water supply plumbing  110  rest within the cavity  138  of the pre-formed sill  130 . During installation, the securing nuts  152  are removed, the connection pieces  148  pushed through the apertures  140 , and the securing nuts  152  reapplied and tightened so that the top surface  142  of the pre-formed sill  130  is sandwiched between the securing nuts  152  and the flanges  150  disposed on the unions  146 . This is preferably performed after a waterproof membrane  154  has been applied to the sill form  130 .  
      Referring to  FIGS. 2, 3 , and  6 , initially the coupling assemblies  144  may be attached to the sill form  130  by screws  216  threading into apertures  156  in the flange  150 . This is typically a temporary arrangement until the securing nuts  152  are fitted. The base  158  of the connection pieces  148  may have a larger thread diameter than the distal end of the connection pieces  148 . As best shown in  FIG. 6 , this allows a protective cap  160  and water supply test plug  162  to be fitted at the factory and the securing nut  152  slid over the protective cap  160  to the base  158  for securing without the protective cap  160  having to be removed.  
       FIG. 6  illustrates in greater detail the connection piece  148  in conjunction with the protective cap  160  and plug  162 . The plug  162  is sized and configured to be sealingly received by the connection piece  148  for the purpose of water pressure testing. Moreover, the plug  162  prevents water flow out of the connection piece  148  so that the system can be pressure tested and/or pressurized prior to installation of the remaining components of the shower assembly.  
      The protective cap  160  includes indicia  212 , such as visual or physical markings disposed on the side of the protective cap  160 . The indicia  212  act as a guide to aid in the placement of material upon the sill form  130  at a predetermined height. Preferably the indicia  212  marks a maximum finished tile height, but the indicia  212  may also mark other heights, such as a minimum tile height. In the illustrated embodiment, the maximum finished tile height is indicated by a line disposed partially around a circumference of the protective cap  160 .  
      The protective cap  160  protects the threads of the connection piece  148  during installation and allows, with the use of the plug  162 , a plumber to pressure test the system. To remove the protective cap  160  from the connection piece  148 , the plug&#39;s  162  hexagonal head is loosened with a crescent wrench or spanner. The threads of the plug  162  may engage the protective cap  160  to assist in lifting the protective cap  160  from the mortar/grout applied to the sill form  130 . Alternately the protective cap  160  may be cut with a box knife or similar device leaving a portion of the protective cap  160  disposed below the finished tile height and/or imbedded below the tile surface.  
      To help rotationally orientate components, such as the cam portion  178  (which will be described in more detail below), on the connection piece  148 , the connection piece is keyed or indexed. In the illustrated embodiment, this is provided by one or more keyways  218  (one shown), which are in the form of flat faces which extend vertically down the opposite sides of the connection piece  148 . These flats or keyways  218  extend at least to, and preferably below, the bottom edge of the protective cap  160  (see  FIG. 6 ) once fitted—i.e. they will extend at least to and preferably below the typical finished tiled surface which may be applied to the sill form  130 . The keyways  218  may be substantially diametrically opposite each other as illustrated or alternately, may be misaligned to impede certain components being accidentally placed 180° out of rotation from the correct orientation of the component.  
      Referring to  FIGS. 4 and 5 , a quick connect assembly  174  will now be described. The quick connect assembly  174  provides means by which the hollow support column  112  can be fastened to the sill assembly  106  in a quick connect manner. More specifically, the quick connect assembly  174  includes an upper interlocking member or interlocking sleeve  180  and a lower interlocking member or cam portion  178 . The interlocking sleeve  180  is coupled to the bottom of the hollow support column  112 . The interlocking sleeve  180  interacts with the cam portion  178  by a bayonet type action. The exact rotational orientation of the hollow support column  112  is defined by the rotational orientation of the cam portion  178 . Thus, the cam portion  178  of the illustrated embodiment is keyed to interact with the keyway  218  of the connection piece  148 .  
      Moreover, the cam portion  178  includes one or more keys or inward protruding flat surfaces  204  and  206  disposed in the inside of the cam portion  178 . These keys or flat surfaces  204  and  206  are sized and configured to interact with keyways  218  disposed on the connection piece  148  such that the cam portion  178 , when interfaced with the connection piece  148 , is oriented in a selected angular orientation relative to the sill form. The keys or flat surfaces  204  and  206  of the illustrated embodiment appear as filled in chords within an inner circular aperture of the cam portion  178 .  
      The cam portion  178  includes outwardly extending protrusions  208 . The interlocking sleeve  180  similarly has inwardly extending portions  210 . During installation, the hollow supporting column is rotated such that the protrusions  208  on the cam portion  178  may pass through the gaps between the inwardly extending protrusions  210  of the interlocking sleeve  180 . Once the interlocking sleeve  180  has been placed about the cam portion  178 , the support column  112  and the interlocking sleeve  180  are rotated (preferably less than 360 degrees) so that the protrusions  208  on the cam portion  178  overlie the related protrusions  210  on the interlocking sleeve  180 , locking the support column to the sill assembly. Detents or barbs may be provided on the cam portion  178  and/or the interlocking sleeve  180  to ensure that once rotated into a locked position, the support column cannot be as easily rotated for release.  
      Turning to  FIG. 2  and focusing upon the method of installation, leaving aside modifications to the rest of the shower wall interiors, a membrane layer  154  is generally applied prior to the installation of the securing nuts  152  which go over the top of the membrane layer  154 . The preference is for a liquid coating membrane layer  154 , although solid sheet type membrane layers  154  may also be used. Solid sheet type membrane layers  154  will need to be trimmed to allow the connection pieces  148  to protrude there through. Preferably, the protective caps  160  are positioned over the top end of the connection pieces  148  and the water supply test plugs  162  fastened to the connection pieces  148 , if not already present, before application of the membrane layers  154  or other layers.  
      Referring to  FIGS. 2 and 6 , next a bedding layer  164  of mud, mortar or other suitable mix is applied. This bedding layer  164  is usually reinforced with a mesh  166 . The installer can then build upon the bedding layer  164  up to a desired thickness and contour appropriate for the chosen tiles as per normal practice. The protective cap  160  includes indicia  212 , such as a visual line or physical mark that indicates a maximum mortar/tile height. The indicia  212  should be used as a guide for installers such that they do not build up past the maximum height of the finished tiled surface.  
      Next, tiles  168  may be applied using a suitable tile adhesive  170 . After this stage, the water supply test plug  162  and protective thread cap  160  may be removed and a sealant layer (not shown) optionally laid over the tiles  168 . This sealant layer may be formed from a compressible or flexible sealant type material to prevent the ingress of water into the installation.  
      Referring to  FIG. 4 , a tapered spacer or washer  172  may be used to help level the surface should an incline have been provided to assist in draining of water from the tiled surface back into the shower pan or base. The tapered washers  172  have a thickness that is tapered across the width of the washer. Preferably, a set of tapered washers  172  are provided, the set including tapered washers  172  of various tapered thickness. One or a combination of these tapered washers  172  may be used as required. These tapered washers  172  may be keyed to interact with a flat or keyway  218  ( FIG. 6 ) disposed on the connection piece  148  such that the direction of taper of the tapered washers  172  is oriented perpendicular to the length of the sill form  130 .  
      A flat washer  176  may be provided over these tapered washers  172 , followed by a cam portion  178  and a securing nut  214 . The securing nut  214  may be tightened down to hold everything firmly upon the connection piece  148 .  
      Preferably, the hollow support column  112  is pre-plumbed with an internal conduit  182  supplying water to the body water jets  108  which are positioned at appropriate intervals along the height of hollow support column  112 .  
      Connection of the internal conduit  182  may be via a number of methods. For instance  FIG. 4  illustrates a coupler  186  which may be threaded to the connection piece  148 . Alternately, the internal conduit  182  of the hollow support column  112  may be coupled to the connection piece  148  by a quick to connect type fitting, such as a John Guest type fitting. A quick to connect fitting allows the coupler  186  of an extendable portion  190  of the internal conduit  182  to be pulled down and fitted to the connection piece  148  by pushing the coupler  186  toward the connection piece  148 .  
      In an alternative arrangement the internal conduit  182  is rigid and non-extendable and the coupler  186  is a push fit coupler. The push fit coupler  182  may be pushed inside the top end of the connection piece  148  to provide a water tight seal therein as the hollow support column  112  is coupled to the sill assembly  106 . As should be apparent to the those skilled in the art, although two types of couplers are illustrated and/or described for coupling the internal conduit  182  to the connection piece  148 , other couplers are suitable for use with the present invention and are within the spirit and scope of the present invention.  
      The hollow support columns  112  are connected to the sill assembly  106  in a quick connect manner as described above. This secures the hollow support column  112  to the threshold sill assembly  106  such as illustrated in  FIG. 3 . The shower enclosure  102  may be completed as substantially shown in  FIG. 1  by the installation of a pair of side panels  196  and  198  and by coupling the door  120  to one of the support columns  112  by a pair of hinges  118 .  
      While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. For instance, according to one embodiment formed in accordance with the present invention there is provided a pre-plumbed shower threshold sill assembly including a sill form, one or more apertures in a top surface of the sill form through which a connection portion for a water conduit can protrude, and plumbing within the sill form leading from the connection portion to an end of the sill form.  
      At least part of the connection portion that extends above the top surface of the sill form may be threaded. The sill assembly may include a nut complementary to the threaded portion of the connection portion, the arrangement between the nut and connection portion being such that the nut may be loosened and positioned near the threaded free end of the connection portion to allow the connection portion and connected plumbing to be lowered substantially within the threshold/sill form during transport. The nut can be subsequently tightened to raise the lowered connection portion to its correct height for use, and to lock the connection portion and associated plumbing into place for use.  
      The connection portion may be coupled to a union that substantially comprises an elbow or T-shaped coupling member. The threaded portion of the connection portion may be keyed or indexed to limit the rotational orientation of one or more additional components placed over same. The threaded portion may be keyed or indexed by the presence of at least one longitudinal slot or flat face on its outer surface. The flat face may be oriented so as to be parallel to an imaginary line tangent with the outside surface of the threaded section. The sill assembly may include one or more apertures in the top surface of the sill form, wherein the connection portions extend through the apertures, and wherein the connection portions are connected together in parallel by the plumbing.  
      The plumbing may include one or more of a flow control valve, a mixer, a pressure regulating means, a body spray jet, and a shower head. The end of the plumbing at an end of the sill form may be terminated by a connection means for the attachment of a supply pipe or plumbing. The outside of the sill form may be textured to improve the adherence of a liquid membrane coating. The sill form may be ribbed, or otherwise modified on its inside to increase its rigidity. The sill form may be of a material able to be trimmed to length by a handsaw, power saw, or grinder. The sill form may be made of at least one of the following materials: aluminum, an aluminum alloy, another metal or alloy, a moldable or extrudable plastic material, a fiber reinforced plastic, and a fiber reinforced cementitious material. The sill form may be precoated with a waterproofing membrane material.  
      The connection portion may be threaded and keyed, wherein the keying does not interfere with the threading of components upon the threads of the connection portion. The connection portion may be coupled to a union comprising substantially a right-angled elbow or a T-shaped joint. The connector portion may terminate in a flange disposed near or at the termination of the threads of the connection portion. A nut or associated nut flange may be threaded upon the threads of the connection portion to sandwich the thickness of the top surface of a preformed sill of the threshold assembly between the flange and the nut. The flange may accommodate screws or mechanical fastening means allowing the flange and connection portion to be fastened to the preformed sill form. The threaded sections of the connection portion may include at least two different outside diameters adjacent each other on the portion of the connection portion which extends above the top surface of the sill.  
      The sill assembly may include a cam portion which is able to engage with an engaging portion, the cam portion being substantially annular and disc-like and including at least one outwardly directed feature adapted to extend into a hollow central portion of the engaging portion. The cam portion may include a key which interacts with a keyway or face on the connection portion. The sill assembly may also include an engaging portion, wherein the engaging portion is associated with a column or structural element which is able to be connected to the cam portion. The connection of the engaging portion to the cam portion may be by substantially a bayonet action. The cam portion may be able to be secured to the threaded portion of the keyed connection portion, substantially as described above, by placing over same, and tightening a retaining nut or a retainer mechanism over the threaded portion.  
      The sill assembly may include at least one of the following: locking washers, spacer shims (washers), tapered wedge washers which taper in thickness, and a protective capping piece—all characterized by being placeable over the threaded keyed portion of the keyed connection portion.  
      In accordance with one embodiment formed in accordance with the present invention there is provided a kit for forming a tileable shower sill. The kit may include a sill form with at least one aperture in a top surface, at least one keyed connector portion with a threaded keyed end passable through the aperture, and plumbing connected or connectable to a the keyed connection portion to an end of the sill form. The kit may also include a protective cap removably placeable over a keyed threaded end of the keyed connection portion. The protective cap may be a one piece unit. The protective cap may have an aperture disposed in the top allowing a plug to pass through and connect to the end portion of the connection portion. The kit may include a cam portion, substantially as described above. The kit may also include at least one hollow support member having an engaging portion selectively couplable to the cam portion.  
      The kit may also include a shower door attachable to the hollow support member, a return panel, and a hinge set for pivotally coupling the shower door to the hollow support member, spray jets positioned or positionable in the hollow support member, and plumbing for connecting the connector portion to the spray jets. The hollow support member may include at least one spray jet and the hollow support member may be internally preplumbed. The internal plumbing of the hollow support member may terminate near the base of the hollow support member, and may be terminated to allow connection to the keyed connection piece with which the hollow support member is associated. The keyed connection piece and terminated end of the internal plumbing of the hollow support member may be able to form a quick connection, the quick connection including a push-fit or bayonet fit connection.  
      According to a further aspect of one embodiment formed in accordance with the present invention there is provided a method of forming a pre-tiled shower sill/threshold capable of supplying water to components attached or placed partway along the length of the sill, the method comprising:  
      optionally trimming a sill form to length; 
          providing aperture(s) in the top of the sill form where supporting structures are to be attached to the sill;     passing a threaded keyed portion of a keyed connection portion through the aperture and securing in place with a nut;     providing plumbing within the sill form to an end of the sill form and connecting to a water source in the existing structure; and     securing the sill form to the floor or supporting surface.        

      The method may also include: 
          placing a removable cap over the exposed threaded end of the connection portion(s), the length of the cap or markings on the cap being chosen to signify the height of at least one of: the finished tile surface and the height of mortar substrate under the tiles;     extending the shower floor membrane over the sill forms;     applying a cementitious substrate over the sill form;     tiling over the substrate; and     removing the cap(s).        

      The method may also include: 
          placing tapered shims or washers over the exposed keyed portion of the connector portions to create a level surface;     placing a keyed cam portion, substantially as described above, over the exposed keyed portion of the connection portions and securing the keyed cam portion in place with a nut or ratchet engaging fitting device;     connecting at least one hollow supporting member having an engaging portion attached thereto to the shower sill, the engaging portion interlocking with the cam portion to couple the hollow support member to the shower sill; and     finalizing any plumbing connections within the hollow supporting member, either prior to or at the time of its attachment.        

      The hollow support member may be pre-plumbed. The method may include attaching either or both door panels and return panels to the hollow support members. The hollow support member may or may not include at least one of the following: spray jet, oriented substantially horizontally, a shower rose, or faucets.  
      The method may utilize a pre-formed shower sill. This pre-formed shower sill is typically a hollow or open element (e.g. U-shaped or C-shaped) to allow internal plumbing to be suitably positioned or provided within a cavity formed by the pre-formed shower sill.  
      Preferably, the pre-formed sill acts as a suitable supporting substrate for finishing layers of mud, mortar or bedding mix, adhesive, and tiles to be overlaid. In this respect it is preferable that the sill is relatively rigid and resistant to flexing so as to avoid cracking of any overlying layers. Suitable strength and rigidity can be accomplished by a number of means including suitable choice of materials and appropriate design. It is anticipated that the typical skilled tradesperson would be well acquainted with aspects of design and material to construct a suitable sill in light of this detailed description. For instance, and by way of example (but not limited to), materials of construction may include various metals including aluminum and its alloys, various plastic materials, including moldable or extrudable materials, and fiber reinforced plastic materials.  
      Elements of design which may be used to improve strength and rigidity can include internal ribs and reinforcing elements of different materials. A separate insert which fits inside the sill form after it has been plumbed may also be considered to improve strength. Injecting expandable foams is another option, which can increase strength and rigidity as well as providing additional internal insulation to plumbing provided therein.  
      The environment in which the sill is to be used may also be considered. In preferred methods of use of the present invention there is an overlying waterproof membrane layer which will protect the pre-formed sill from water impregnation. Hence while materials such as steel, which is susceptible to corrosion by water and air, may be considered and are suitable for use with the present invention, it is preferred that a suitable anti-corrosive coating (e.g. zinc coating) or protective coating (e.g. plastic or epoxy coating) be used.  
      The pre-formed sill/threshold may take a number of shapes. In cross section the pre-formed sill/threshold is preferably hollow so as to allow for the passage of internal plumbing there through. Accordingly the pre-formed sill/threshold may be formed to have a square shaped cross section, though in preferred embodiments the cross section of the sill is U-shaped or top hat shaped. The cross section need not be constant along the entire length. It should be considered however that for most embodiments of the present invention the sill/threshold will be overlaid with various layers of materials and finally finished with tiles. Accordingly it is envisioned that in most cases the major outer surfaces of the pre-formed sill will be substantially flat and external top and front/back faces can be either perpendicular to each other or tapered (with a slight incline applied to the top surface to assist water drainage).  
      In plan view, the shape of the pre-formed sill may vary. In the simple embodiment the sill may be substantially linear. However in more sophisticated embodiments, the sill may be curved, or perhaps curved along only part of its length. Angles may also be introduced so that the final sill can take any of a number of possible shapes according to user and manufacturer preferences. This would allow the pre-formed sill to be used in various designs, as well as alcove, corner, and angular showers, which extend from one or more walls etc. The pre-formed threshold/sill may also be made from material which can be cut to size on site. This would allow a user to trim the pre-formed threshold/sill to fit a particular installation, using commonly available tradesperson/home handyman tools such as handsaws, power saws, hacksaw and/or grinders. The choice of material will be a consideration in such embodiments.  
      Modifications may be made to the outer surface of the sill. For instance, in preferred installations there will be a membrane layer applied directly over the sill. The membrane layer may be a sheet of material or a liquid membrane coating. Accordingly the outer surface of the pre-formed sill could be modified to increase adherence of liquid coatings. This might be accomplished by texturing so as to allow a keyed bond, or by coating with materials to which the applied membrane coating is particularly adherent.  
      The pre-formed sill should ideally contain provisions for fixing to the floor and/or supporting substrate. For a pre-formed sill of “U” or top-hat cross sectional configuration, suitable aperture holes may be provided or drilled in the lower vertical or lower outwardly extending flanges. This enables the pre-formed sill to be mechanically fastened to a floor by devices such as screws, etc. Adhesive bonding may also be considered.  
      The use of separate connectors may also be considered in various embodiments as well, e.g. a channel section fixed to the floor over which the sill is positioned. These may click together for fitting or rely on mechanical or adhesive fastening. Various fastening tabs may also be formed or attached to various points along sills of other cross sectional configuration.  
      Typically there is provided in the top surface of the sill one or more apertures through which plumbing may extend. While such apertures may be formed on site, allowing the installer to precisely locate apertures according to the shower equipment (e.g. doors and supporting columns, etc.) to be used in conjunction with the sill, preference of the present invention is for these apertures to be pre-formed. By pre-forming the apertures, it is also possible to pre-plumb (and pressure test) a threshold/sill assembly which can assist in minimizing warranty problems after installation and significantly improve installation time. In the preferred embodiment of the invention to be described later, the use of the specific plumbing hardware described below can further aid quick and accurate installation of shower equipment (e.g. supporting columns for doors, etc.).  
      Ideally in the pre-plumbed sill/threshold assembly, there are provided connection pieces able to extend above the apertures in the top surface of the pre-formed sill. These are connected within the interior of the threshold sill assembly to lead to at least one end of the sill assembly. The plumbing at this end may be suitably terminated either by cutting to length, or provided with a suitable typical plumbing connection piece to allow connection to existing plumbing within the wall of the existing building structure. In practice, additional plumbing within the wall or from the floor may be required to route water from a shower&#39;s faucets, mixer, or diverter into the plumbing of the sill. This however may be performed by standard plumbing practices and typically accomplished by the plumber at the time of installation of the present invention.  
      The preference for most embodiments of the present invention comprising a pre-plumbed threshold sill assembly is for the top portion of the connection pieces extending above the apertures in the top of the sill to be threaded. Threading can provide a number of potentially realizable advantages including allowing easy connection of other components to the connection piece—the connection piece thereby acting as both a locating and partial-supporting element for connected fixtures.  
      Additionally however, the threads provide a useful advantage during transport in that a securing nut can be wound back until it is positioned near the top of the thread. At this point, the securing nut will rest on the top of the threshold sill assembly while the rest of the plumbing is lowered so as to be disposed within the hollow interior of the pre-formed sill. When preparing for installation, the securing nut can be tightened so that the connection piece, with which it is associated, is raised to its correct height and is locked into position with respect to the top of the sill. Ideally a flange formed integrally with the connection piece presses against the underside of the top surface of the sill while the securing nut presses against the top surface of the sill.  
      Alternatively the securing nut can be fitted to the pre-plumbed assembly when it is separate of the preformed sill. The pre-plumbed assembly can be transported within the sill assembly, or even separately thereto. During assembly, the securing nut can be removed, the end of the connection piece passed through the aperture in the sill assembly, and the securing nut reattached to the threaded end of the connection piece and tightened.  
      While the aforesaid method, with the securing nut acting as the primary means of securing the pre-plumbed assembly to the sill, is suitable for techniques where liquid membrane layers are applied, the arrangement can be a little troublesome when blankets are used. Attempting to get blanket layers to adequately seal about and sit over the nut (which rests above the top surface of the sill) may be problematic. To address this issue, the illustrated embodiment has a provision for securing the connection portion to the sill by means in which the top of the sill remains substantially flat and level up to the protruding connection portion. A blanket membrane with an aperture conforming to the position and diameter of the protruding connection portion can then be placed over the connection portion and flat against the top of the sill. The securing nut and washers can then be fitted to sandwich the blanket membrane beneath it.  
      The underside of the connection piece may take a number of forms. In preferred embodiments it comprises substantially an elbow to allow for the ready connection of a pipe leading to an end of the sill assembly. Where more than one connection piece is used to provide water above the top surface of the sill, additional connection pieces may comprise a T-connection on the underside of the top surface. However, to allow for balanced pressure and flow, various other methods and connection pieces may be considered.  
      In various embodiments of the present invention, which are pre-plumbed, water is eventually routed to water delivery devices positioned above the sill structure. While various devices may be used, it is envisioned that the most common form of water delivery device is a body spray nozzle or jet. These will typically be body spray jets, which provide a substantially horizontal spray of water or mist against the body of the user of the final shower assembly. A problem in the past has been the difficulty in providing water to such jets and manufacturers have been largely restricted to specifically designed shower units which are often free standing or wall mounted. However, the plumbed threshold sill assembly formed in accordance to the present invention provides a relatively easy method of routing water to such devices positioned above a sill assembly, even in instances where the threshold sill assembly is to be tiled according to substantially traditional techniques.  
      In the past this option was not available and any body spray units would need to be installed on existing walls of the building structure, or shower panels directly attached to walls of the building structure. Attempting to route water to free standing columns (i.e. columns or supports not directly attached to an existing wall of the building structure) was problematic and typically required visible overhead plumbing. A further disadvantage of panels positioned against existing walls of the building structure is that they typically direct the spray towards, or substantially towards, the door of the shower assembly. Many shower doors do not provide adequate sealing to prevent such volumes of spray from leaking outside the door. Hence, as will be seen later, the present invention in its various forms can provide a shower assembly in which spray jets can be provided in structures positioned above the sill assembly, and oriented in a manner in which they spray away from the door. This represents an advantage over what was achievable before the present invention.  
      In the preferred embodiment of a shower assembly or installation kit, hollow support members having internal plumbing supplying water delivery devices such as body spray jets and nozzles are used. While the exact details may be varied in different embodiments, for simplicity the description will generally be restricted to such an arrangement, although it should be apparent to those skilled in the art that other arrangements are suitable for use with and are within the spirit and scope of the present invention.  
      Preferably in such an arrangement, use is made of a cam locking system (which will be described further later), and which is the subject of the inventor&#39;s separate U.S. patent application Ser. No. 10/804,573, filed Mar. 18, 2004, and entitled Connection Assembly Apparatus and Method, the disclosure of which is hereby expressly incorporated by reference. While such an arrangement does not need to be used, a much easier installation with a tidier finish can be accomplished by using such an arrangement. Again the following description will be centered predominantly on such an arrangement being used, although it should be apparent to those skilled in the art that other arrangements are suitable for use with and are within the spirit and scope of the present invention.  
      The connection portion extending above the top surface of the sill has been previously mentioned and described. However a desirable further feature of such a connection portion is that it is keyed in at least part of the portion extending above the top surface of the sill. This keying allows for the accurate orientation of additional components which may be placed above the top surface of the sill during finishing of an installation. It also allows the taking into account of height variables and height adjustability to accommodate varying thickness of substrates. These may, for instance, include spacers, various shims and washers, tapered shims and washers, locking cams, etc. There are a number of reasons and potentially realizable advantages for providing such a keyed system. For instance it is relatively common practice for tilers to provide a slight incline in the finished top surface of the sill so as to drain water back towards the inside of the shower assembly. In such a case the tapered shims or washers may be required to level off the top surface of the sill assembly, immediately about the extending connection portion, so as to allow the accurate vertical orientation of subsequently attached components. For instance, where the interlocking cam connection system is used, it is preferred that the cam be in a horizontal plane if the resulting attached column is to be truly vertical. Providing a keyed relationship between such tapered washers and the connection piece about which they are placed, helps hold the washers and spacers in the correct orientation and prevents their rotation during subsequent finishing of an installation.  
      Keying of the top portion of the connection piece may be accomplished in a number of manners. Ideally one or more slots, keyways, or faces may be provided through the threads so that they do not interfere with the function of the thread themselves. The interacting washers or cams etc. may then merely include one or more protrusions which extend within these slots, keyways, or faces as they are slid down the connection piece. Various numbers of slots and other keyed arrangements may be considered in various embodiments of the invention, though the slot, keyway, or face arrangement is considered a preferred embodiment.  
      Also associated with the connection piece may be a “Protective Cap” which can be slid over the top end of the connection piece preferably before an installation operation. The primary reason for providing this cap is to protect the threads and opening of the connection piece from foreign material, which may interfere with subsequent operation. Hence a plastic (or other material) cap may be provided.  
      The cap may include an aperture in the top end allowing it to be used in conjunction with a plug. Such a plug may pass through the aperture in the top end of the protective cap and be threaded into internal threading on the top end of the connection portion, though several alternate options exist. Hence the plug may be screwed into the internal threaded section of the connection portion which enables the preplumbed assembly to be blanked off for pressure testing by the plumber.  
      As an alternative, the protective cap, which covers the threaded section of the connection portion protruding above the threshold, may be modified by incorporating into its top a male threaded section which acts as a plug when screwed into position. The protective cap has smooth interior walls (i.e. the walls disposed against the threaded portion of the connection portion are smooth and not threaded) but has a reverse taper on the outside so as to allow easy removal from mortar or grout. The integral “union plug” has a hexagonal nut molded (but not exceeding the protective cap diameter) to the top to aid and assist rotation and removal of the protective cap from the threaded section of the connection portion and from the mortar/grout once the sill is tiled.  
      A further alternative method is to form a hole in the protective cap and have a union plug as a separate component which has male threads and a hexagonal head. The union plug may be manufactured from a rigid material, one suitable example being a metal, such as brass. For assembly purposes, the protective cap would be placed over the threaded connection piece, then the plug screwed into position via the internal thread. Once screwed into position, the plug would act as a seal permitting the plumbing of the system to be pressure tested. Generally the water pipes are capped with bungs and left under pressure for some time during construction until after wall linings and tiling has been completed. After tiling has been completed, the main water pressure is turned off, the piping drained, and the bungs removed for plumbing decorative fixtures and faucets thereto. Plugs generally have to withstand water pressure for a considerable amount of time during construction.  
      Although various embodiments of plug and cap assemblies have been discussed, for the remainder of the specification, the various options shall be discussed synonymously unless specifically stated or expressed.  
      The cap may include indicia to act as a guide as to the maximum height of the finished mortar or substrate prior to application of the tiles or marble surface which is to be built up over the sill. It can also indicate maximum finished tile height. The indicia may come in many forms, a few suitable examples being the bottom edge of the cap and a predetermined visual or physical mark or indicator on the side cap, such as a line drawn partially or fully about a circumference of the cap.  
      The indicia may be used to indicate to a user a height which any finished tile (or other surface) mortar or grout should not extend above if the remaining components are to be accurately and reliably connected. Hence there is provided an effective visual or physical guide for the finishing of the layers overlying the pre-formed sill.  
      A typical shower installation with doors and body spray jets will now be described by way of example only. Again this is representative of various other embodiments which may take effect in various embodiments of the present invention. It should also be envisioned that the various steps may be modified according to local practices, which do differ from region to region. It is envisioned that the present invention is relatively flexible and can accommodate such variations in local practice, and changes in governing regulations for wet area installations. Hence the following description should be regarded as representative guide only and that the skilled trades person will be able to adapt the method of the description to accommodate their preferred and local practices.  
      In the present example, it is assumed that an apron bath in a three-walled alcove is being retrofitted with a tiled shower installation. Accordingly, initial preparatory steps should be performed such as removal of the bath and supporting structure. This should be followed by attending to in wall pre-plumbing such as the routing of water to a mixing valve assembly volume control valves or faucets and directing water to the vicinity of outlet devices such as shower roses, hand held spray devices, and other water supply devices that are to be provided within a shower installation. Additionally a water supply should be routed to a point near one end of the threshold sill assembly that is to be formed. In the present invention it is envisioned that a pre-plumbed threshold sill assembly is being used.  
      The threshold sill assembly will be attached to the floor at a suitable time. If necessary the threshold sill assembly may be trimmed to size to accurately fit within the opening. Most tiled shower installations will also require a receptor base to be built up and wall linings to be initially applied. The attachment of the threshold sill assembly to the floor can be integrated into these steps.  
      At the time of installing the pre-plumbed threshold/sill to the floor, the securing nut for the connection portion should be tightened. This will tightly fix the connection portion to the pre-formed sill, and extend the top exposed portion of the connection piece to the correct height above the top surface of the sill. A protective cap should also be positioned over the top end of the connection piece at this time, though preferably this has been installed at the factory. The end plumbing connection from the end of the pre-plumbed threshold sill assembly should also be attached to the tempered water supply from the mixing valve or faucets at the time of installation of the threshold/sill assembly. Pressure testing of the plumbing may also be performed.  
      The next step is installation of a shower drain and lumber supports between joists for membrane support. A waterproof membrane is provided over the shower base and sill. This should be appreciated that the receptor, in the context of the present invention, will generally mean the bottom lower region of the shower installation. In many tiled installations a separate receptor portion will not be visible and the vertical walls will extend vertically down to meet the bottom tiled floor assembly—such installations being typically different in appearance to standard molded receptor and panel assemblies. Many regulations in different regions require the membrane layer to extend to certain height from the floor of the shower to above and beyond the threshold installation. Thus the term shower tray is used herein for typically referring to that portion of the base of the shower up to the typical finishing height of the waterproofing membrane coating.  
      Hence the liquid membrane coating or sheeting/layer may be applied according to standard techniques. According to local practice the liquid coating (e.g. “HOT MOP™”) or sheeting blanket is overlaid over the threshold/sill and tray areas of the shower as per normal practice and regulations.  
      Typically next, various bedding mud and mortar layers are built up in the shower tray region with a suitably thick layer of this material built up over the threshold/sill. Again local practice is relied upon, and reinforcing materials such as metal lath, or meshes are often incorporated into such layers. At the time of providing such a layer over the threshold/sill assembly, consideration is given to the maximum height indicated on the protective cap to ensure that the finished tile surface will not extend above the predetermined and indicated maximum levels indicated on this protective cap. It is however acceptable that the finished tile surface be below this predetermined indicated level.  
      After the bedding/mortar layer, suitable tile adhesive is generally applied and the tiles installed. Grouting typically follows.  
      At this stage the protective cap is removed or cut away and a support washer placed over the exposed threaded connection piece. The primary purpose of this support washer is to help spread the load of additional components as they are tightened down against the top surface of the tile. This support washer may be partially resilient or compressible, and may comprise a metal or plastics material.  
      Any preformed tapered shims or washers which counter any slope or incline which has been formed by the tiler into the top surface of the sill are applied. These can be used singly or in combination to counter the slope present so as to provide a finished horizontal or level top surface.  
      Once the top of the washers have been leveled to horizontal, a cam portion is rotated appropriately and positioned over the threaded portion of the connection piece. Again the keyed relationship between the cam and top end of the connection portion will help suitably orientate the cam portion and maintain this orientation. Ideally the keyed arrangement should be such that the cam portion can only be placed over the connection piece in the correct orientation. This is assisted by the use of integrally marked arrows, and indicators indicating the direction of orientation and degree of thickness variation, which is typically greater towards the inside of the shower receptor. This will be particularly important, as the correct rotational alignment (and slope adjustment if required) of the supporting columns (see later) is dependent upon correct rotational orientation and alignment of the cam portion with the horizontal plane.  
      Finally, at this stage, a tightening nut is placed on the connection piece and tightened down against the cam portion. Locking washers may also be included.  
      At this stage, final assembly of the shower front is generally accomplished. Ideally a pre-plumbed hollow support member is used. This support member will typically comprise a hollow element, which is pre-plumbed, and which already contains body jets, or other spray and water delivery devices in its outer walls. Hinges or fixing means for doors and panels may also be provided, or pre-drilled apertures for the subsequent fixing of such components.  
      Associated with the bottom end of the hollow support member is a locking sleeve which can interact with the cam portion. Ideally this cam portion interacts in a bayonet type action allowing the hollow support member (and interlocking sleeve) to be positioned over the cam portion and lowered down to substantially contact the top surface of the tiled sill and/or washers etc., and then rotated to orientate and lock/secure the support column in place. At this stage, the support column should be resistant to upward lifting movements. The arrangement should also be such that the support column can only be placed and fitted over the cam portion in one orientation, this being the correct orientation. Hence, once fitted, the hollow support portion should be in such a position that it is correctly orientated (i.e. rotational orientation) such that door hinges, spray jets, and fixing devices or means for other components, are orientated in the correct direction.  
      Ideally, the internal plumbing of the column is such that a rotatable or push-fit type of connection is achieved with the connection piece as the column is lowered into position. However, the use of a flexible internal pipe portion, which can be extended down to allow connection to the connection piece is also suitable for use with the present invention. A variety of different couplings and fittings which allow a watertight connection to be made are known and are suitable for use with the present invention.  
      Typically next, the finishing of the shower front is accomplished. This generally involves the fixing of side return panels, doors, and etc. as well as fitting any top reinforcing or strengthening rails, etc.  
      This represents a typical installation according to certain embodiments of the present invention and, as mentioned before, specific embodiments and methods of installation may vary within the scope of the present invention.  
      By way of further example, some further comments are made on the nature of the cam portion and associated interlocking sleeve assembly. This general arrangement may be as described in previously mentioned U.S. patent application Ser. No. 10/804,573.  
      In one respect, such an arrangement as described in U.S. patent application Ser. No. 10/804,573 may be described as a connection system consisting of a pair of cooperatingly formed engaging portions, one of which engaging portions is coupled to a member to be attached to a surface or structure. The other engaging portion is attachable to the surface or structure (which may be during or post-construction depending on the embodiment). The engaging portions preferably interact and engage with a partial rotational and/or bayonet type action. Preferably the connection arrangement is substantially hidden, except by user choice, when the member is ultimately attached to the surface or structure by cooperative engagement of the engaging portions. Preferably one engaging portion can be considered a cam or cam-like arrangement which interacts with the second engaging portion which can be likened to an annular sleeve. The engaging portions are preferably hollow or have removed portions to allow plumbing or services to pass from the surface (or structure) through to the building element being attached. The building element may be pre-plumbed and/or pre-wired.  
      Preferably, one of the engaging portions is a cam portion is typically disc-like in appearance with outwardly extending flange portions are present at the top outer face of the engaging portion. Preferably these outwardly extending flange portions interact with similar flange portions disposed on the other engaging portion.  
      The other of the engaging portion is preferably annular in appearance and is also hollow in its middle to allow plumbing, and/or electrical services there through. Extending radially inwards into this cavity/aperture are flange portions which interact with the flange portions on the above-described engaging portion. These are positioned and sized commensurately, so that the flange portions overlap when suitably rotated. The engaging portion is affixed to or integrated to a member such as a support column.  
      In practice the column assembly can be lowered over a first engaging portion secured to a surface or structure. Once lowered, the assembly can be rotated so that flanges of both the engaging portions engage/interlock with each other. This arrangement then secures the column assembly from being removed from the surface or structure. The assembly is then securely fastened to the sill surface with no externally visible evidence of attachment.  
      While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.