US3234692A

US3234692A - Tile construction

Info

Publication number: US3234692A
Application number: US340848A
Authority: US
Inventors: Georg Knud
Original assignee: International Pipe and Ceramics Corp
Current assignee: International Pipe and Ceramics Corp
Priority date: 1964-01-16
Filing date: 1964-01-16
Publication date: 1966-02-15
Anticipated expiration: 1983-02-15

Description

Feb. 15, 1966 K. a. BIERLICH TILE CONSTRUCTION 3 Sheets-Sheet 1 Filed Jan. 16', 1964 INVENTOR.

1 TT'OENE'YS.

Feb. 15, 1966 K. G. BIERLICH 3,234,692

TILE CONSTRUCTION Filed Jan. 16, 1964 3 Sheets-Sheet 2 I IIIIIAHII. l-

INVENTOR. ENC/D 65026 B/EQL x04 United States Patent C) 3,234,692 TILE CGNSTRUCTIQN Knud Georg, Bierlich, Los Angeles, Calif., assignor to International Pipe and (Zeramics Corporation, Los Angeles, Califi, a corporation of Delaware Filed Jan. 16, 1964, Ser. No. 340,848 6 Claims. (Cl. 52392) This application is a continuation-in-part of my pending application Serial No. 65,682 filed October 28, 1960, which is being abandoned in :favor of the present application.

This invention relates to a unitary construction or an integrated article made by assembly of a plurality of discrete tile or like bodies and more particularly to a unitary rigid panel construction comprising a multiplicity of discrete polygonal fiat tile rigidly held in spaced relation by a plurality of stiff, rigid elements interconnecting adjacent tile and bonded thereto so that the entire panel assembly may be readily handled as a structural unit.

Tile, such as ceramic tile, is extensively utilized for decorative wall, floor, countertops, and the like, and normally such tile are individually laid in a prepared bed of mortar or mastic. Great care and skill is required in order to position each individual tile in proper spaced relation to adjacent tile in order to provide joint lines which are straight and true and to position the front faces of the tile in a common plane. After the tile are laid in such a bed the joints or spaces between tile are filled with a joint material such as a cement grout. Because of the requisite skill and large amount of time required to properly lay individual tile, various devices and attempts have been made to facilitate the setting of tile by interconnecting individual tile elements, particularly mosaic tile by means of flexible fabrics, strips of material, tapes, and the like so that a pre-assembled group of tile may be handled together. Such prior proposed devices have contributed to the ease in handling and in laying such tile under certain circumstances.

The present invention contemplates a novel unifying construction made by assembling a plurality of individual discrete tile so that a rigid, integrated, readily handlea'ble prefabricated rigid structural unit is provided. The present invention contemplates factory assembly of discrete tile into a unitary panel construction of a size capable of being readily handled, shipped, stored and installed as a structural unit. Preassembly of such tile at the factory rather than at the job site in this manner permits the use of jigs and equipment for the precise, accurate arrangement of selected decorative wall patterns in which each tile may be a component or part of an overall pattern. Final assembly of a plurality of panels containing pattern components may be quickly and readily found, selected, assembled and installed at the job site with a minimum of time and without the extreme care and skill previously demanded when laying individual tile.

The primary object of the present invention is to provide a novel unifying construction for a plurality of individual tile to provide an integrated article of enhanced utility and appearance.

An object of the present invention is to disclose and provide a unitary panel construction composed of a plurality of discrete tile precisely and rigidly interconnected so that the panel is dimensionally accurate and may be handled as an integral structural unit.

An object of the invention is to disclose and provide a tile assembly wherein adjacent tile are interconnected by rigid elongated elements firmly bonded to the tile.

A more specific object of the invention is to disclose and provide a rigid unitary panel construction composed See of a plurality of tile each tile having a back face provided wit-h means cooperable with rigid, interconnecting, elements bonded thereto whereby the tile are positioned, retained and held in a planar zone.

A further object of the invention is to provide a rigid assembly of a plurality of discrete tile in spaced relation wherein the space between tile is at least partially occupied by a rigid tile connecting element, and wherein remaining joint space may be filled with suitable joint material.

A still further object of the invention is to provide such an assembly of tile as above mentioned wherein such a rigid connecting element supports a preformed resilient joint filling member.

Still another object of the invention is to provide a rigid elongated element which may extend for one or more tile lengths and which may cooperate with more than one pair of opposed adjacent tile.

Many other objects and advantages of the present invention will be apparent to those skilled in the art from the following description of the drawings in which exemplary embodiments of the present invention are shown.

In the drawings:

FIG. 1 is a front or plan view of an integrated panel construction embodying this invention.

FIG. 2 is a sectional view taken in the plane indicated by line IIII of FIG. 1.

FIG. 3 is a back view of a tile used in the construction shown in FIG. 1.

FIG. 4 is a perspective exploded view of metal elements used in the construction of FIG. 1.

FIG. 5 is a fragmentary sectional view showing a modification of a metal element.

FIG. 6 is a perspective view of the element shown in FIG. 5.

FIG. 7 is a fragmentary sectional view of another modification of a metal element with a joint filling member adapted for use in a construction similar to FIG. 1.

FIG. 8 is is a perspective view of the metal element and joint member in FIG. 7.

FIG. 9 is a fragmentary front or plan view of a modified panel construction.

FIG. 10 is a perspective view of a metal element used with the construction shown in FIG. 9.

FIG. 11 is a perspective view of the back of a tile used in the construction shown in FIG. 9.

FIG. 12 is a fragmentary sectional view taken in the same plane as that of FIG. 2 and showing a modification of the metal element connecting tile.

FIG. 13 is a perspective view of another modification of a metal element for interconnecting tile.

FIG. 14 is a perspective view of an integrated panel embodying another modification of this invention.

FIG. 15 is a sectional view in the plane indicated by line XVXV of FIG. 14.

FIG. 16 is an end view taken from plane indicated by lin XVIXVI of FIG. 14.

FIG. 17 is a perspective view of a rigid metallic element used in the indication of FIG. 14.

Generally speaking, an exemplary, unitary integrated article or panel construction 10 embodying this invention may include a plurality of ceramic tile 11 arranged to lie in a planar zone in spaced relation and in parallel rows or courses. The panel 10 may be made of any selected length and width and may include square tile as shown or may include other polygonal-shaped tile such as rectangular tile. Each tile 11 is immovably rigidly associated with an adjacent tile by an interconnecting elongated element of rigid material having laterally extending lip portions received within recesses provided on the back face of the tile and bonded to recess surfaces. The space between the tile may be wholly or partially occupied by the rigid interconnecting elements and where partially occupied may be filled with a-joint material of cement grout or a resilient joint filling material or member carried by the rigid elements.

Each tile 11 in this example may be a ceramic tile havinga front decorative face 12 which may be glazed and which may bear a two or three dimensional pattern or a component part of such a pattern. The front faces 12 of tile 11 may lie in a common plane. Each tile 11 may include side edges 14 which are normally opposed to the side edges 14 of adjacent tile. The side edges 14 may be plane, precisely ground and finished so that the pairs of opposite side edges on each tile are in parallel and squared relation, and may include spacer projections or lugs if desired. Each tile 11 has a finely porous rear face which is normally unglazed and which is adapted to be pressed against a bed of mortar or other cementitious material for firmly bonding the tile to the bed of material. The rear face 15, in this example, may be provided with a plurality of polygonal or rectangularly shaped or contoured recesses 16, eachrecess 16 having a recessed surface 17 starting at aside edge 14. Each recess 16 includes recess side walls 18' in parallel relation and a backrecess wall 19. Such a recess 16 is provided at each side edge 14 and in this example is disposed centrally between ends of the associated side edge 14; The recessed surfaces 17 lie in a common plane and the recess walls 18of opposed reces'ses 16'of' adjacent tile are aligned when the side edges 14 of'tile'11- are in selected spaced relation and in vertical and horizontal alignment.

Means for immovably and rigidly interconnecting the plurality" of .dircrete tile 11 mayin this example include a plurality of rigid, metallic elements 22 having portions of T section. In this example a horizontally disposed element 22 may be formed of an integral strip of suitable metal which extends for the length of panel 10. Horizontal element 22 comprises a plurality of longitudinally spaced oppositely directed and laterally extending lips or lateral portions 23 which extend into opposed aligned recesses 16 on adjacent tile. Element 22 also includes a medial leg or longitudinal portion 24 extending the'enti're length of panel and projecting upwardly between the spaced side edges 14 of adjacent tile. The top edge 25 of medial leg 24 is spaced below the common plane of the front faces 12 of said tile.

In this example the oppositely directed lips 23 are each of generally rectangular section and have a planar contour substantially coextensive with planar contour of recess' l'6' so that each lip 23 is provided a close fit between recess walls 18. Thus abutment of edges 26 of lip 23 againstrecess Walls 18 of recess 16 will restrain and hold each tile against movement longitudinally of element 22 and Will positively and precisely position each tile 11in selected spaced relation. The thickness of each lip 23 does not exceed the depth of recess 16 and the back face 27 of each lip 23' may lie substantially in or slightly below the plane of rear face of the tile. The back edge 28 of each lip 23 may normally lie'in spaced relation to the back wall 19 of recess 16 so that side edges 14 of opposed tile may be urged into abutting contact with side surfaces 30 of the medial leg 24 to precisely position the tile in'lateral relation to the element 22.

Each lip 23 may be provided with a through opening 32 which may communicate with an aligned through opening 33 provided in medial leg 24 for receiving and containing a part of the cementing or bonding material 31 by which the element 22 is adhesively secured and fixed to each of the tile 11. It will be apparent that bonding material which fills the

openings

32 and 33 will also provide bonding contact at said openings between opposed side edges 14 of adjacent tile as well as bonding contact with recessed surfaces 17 of adjacent tile. A bonding material may be applied to all of the surfaces of recess 16 including the side walls 18 and recessed surface 17 and may be applied to portions of side edges 14 if desired.

The bonding material 31 may be an organic cement capable of setting or curing as for example an epoxy resin type of cement. Epoxy resins (linear polymers containing epoxide groups) have been found desirable to use as an adhesive'because of their high degree of toughness and structural properties. It is understood, however, that other types of cementitious compositions and adhesives may be employed, as for example, other organic adhesives including urea-formaldehyde type, phenol-formaldehyde types, vinyl compounds, and other compounds containing synthetic rubber or rubber hydrochlorides capable of. providing a strong structural bond between the elements 22 and the ceramic tile.

In this example, rigid, metallic, horizontal elements 22 have been described as extending for the length of panel 10 and interconnecting adjacent horizontal courses of tile. Between adjacent tile of each horizontal course may be a metallic element 22 of identical construction as that of element 22 except that it has a length only sufficient to extend between and abut the medial legs of the adjacent horizontal elements 22 at the intersection of horizontal and vertical joint lines. Elements 22 may be cut from an element 22 at precise lengths and may include only one pair of oppositely directed lips 23. The cooperation between lips 23 and between the recesses 16 in which the lips are received is similar to that described above. Such element 22' may be bonded to the adjacent tile by a bonding material 31 as described above.

In fabrication of the unitary panel construction 10 a plurality of tile 11 may be arranged in a jig of selected dimensions, bonding material applied to the recessed surfaces 17 and/ or to the rigid elements 22, 22', and the elements 22, 22' then positioned between the tile with the lips 23 received in said recesses 16. After the bonding material has set and dried, the unified panel 10 may be placed so that the spaces above the top edge faces 25 of medial legs 24 may be filled with grouting material in well known manner.

To facilitate assembly of two or more panels 10 at the job site, one horizontal edge and one vertical edge of the panel is provided with

elements

22, 22 while the opposed panel edges are not provided with such elements so that adjacent panels'may be interlocked. It should be noted that in this example the rigid element at the vertical panel edge may be continuous and integral as is horizontal element 22. Bonding material 31 may be applied to such mating and interlocking panel edges at the job site, however it will be understood that the mechanical interlock between the panels will serve to hold the panels in aligned relation while the bedding material sets and dries.

The completed panel construction 10 will embody all of the characteristics of a rigid, integrated, unitary, structural panel. The front faces of tile -11 will precisely lie in a common plane and the vertical and horizontal joint lines will be accurately formed and aligned. When the panel construction 10 is handled as a unit it will be readily apparent that the horizontally extending rigid elements 22 serve to integrate and support horizontal courses of tile andthat'said horizontal courses of tile are interlocked against relative longitudinal and lateral movement by the lips 23 which extend between and interconnect horizontal courses and by the medial legs 24. Individual tile in each course are also firmly held by the oppositely directed lips 23 on the elements 22 and as a result an interconnected structurally cooperative metal lic framework lying in the planar zone of the plurality of discrete tile is provided by the metallic elements 22 and 22'. Thus a panel construction 10 made of a selected length and width may be readily handled as a unit and easily installed on a wall or floor or counter upon which a suitable he d of cementitious material has been provided. It will be readily apparent that since only a small portion of the area of the back faces of the tile 11 have been occupied by the metallic lips 23 a major portion of the porous rear face of the tile is available for adhesive and bonding contact with the bed material.

Various modifications of the above described panel construction are contemplated by the present invention. For example, as shown in FIG. 12 the medial leg 24 may be extended so that its top edge face 25 may lie in the plane of the front faces 12 of the tile. Thus, the general appearance of such a tile assembly will be one in which the joints are filled with metal and an inlaid effect may be produced. In such an arrangement, the side edges 14 of the tile are preferably plain and the usual spacing projections are removed.

Another modification contemplated by the present invention is that shown in FIG. 13 wherein longitudinal portions of the medial leg 24 which extend beyond the lips 23 are removed so that a T section metallic element having a length only the length of the lips 23 is provided. In such instance the space between the side edges 14 are filled with a cement grout material. Likewise, the medial leg 24 may be entirely omitted and the lips 23 serve as the sole interconnecting means. It will be apparent that the side walls 18 and back walls 19 of the recesses 16 may cooperate with the side and back edges of the lips 23 in order to rigidly position and firmly hold adjacent tile elements in desired spaced relation.

Another modification is shown in FIG. 5 wherein a metallic, interconnecting element 42 is formed with a medial leg 44, formed as by rolling. Oppositely directed lips 43 may cooperate with recesses 16 in tile 11 as above shown and described. Lips 43 may be provided with perforations 45 so as to receive, hold and contain suitable adhesive material as above described.

A further modification of the invention is shown in FIG. 7 wherein element 52 may be provided with a medial leg 54 of slightly less height and a preformed, flexible, resilient, longitudinally grooved or configured joint filling member 56 may be supported upon a medial leg portion 54 to fill the space between the tile side edges 14. In this example, the joint filling material or member 56 may be made of any suitable plastic or synthetic rubber composition material extruded to a selected configuration. Member 56 may be provided with a longitudinal extending groove 57 which embraces and grasps medial leg portion 54. Member 56 is tightly held between adjacent side edges of adjacent tile and may normally be placed under slight compression.

In FIGS. 911 inclusive a further modification of an integrated assembly of a plurality of discrete tile is shown. A panel construction may comprise tile 11' arranged in parallel courses and wherein a longitudinally extending metallic element 62 includes a flat base strip 63 provided with a plurality of longitudinally spaced, aligned, longitudinal upstanding portions 64 formed as by stamping from the base strip. Base strip 63 may be provided with suitably spaced openings 65 for reception of bonding material such as 31 and the spaced longitudinal portions 64 may carry a resilient, preformed, joint filling member such as 56. In this instance the back face of each tile 11' may be provided with a peripheral marginal recessed surface 67 which extends around the back face of the tile. A joint filling member such as 56 may be omitted and space between the side edges 14 of the tile may be filled with suitable cement grout material in well known manner. Longitudinal portions 64 serve to space and to support and position adjacent tile in proper relationship in the same manner as medial leg 24. In certain instances it may be desirable that the longitudinal portion 64 be made of substantially less height than the thickness of the tile and that the portion 64 be received within recesses provided in the side edges of the tile a djacent to the rear face of the tile or at the elongated recessed surfaces 67 in order to more closely space adjacent tile.

In FIGS. 14-17 inclusive there is fragmentarily illus- 6 trated an integrated article or panel 10' embodying this invention, only a few of the tile being shown so as to illustrate this modification, it being understood that a panel of tile three tiles wide and four tiles long as shown in FIG. 1 may be assembled or fabricated. Reference numerals with a prime sign or following the multiple sequence of the prior modifications will be used to identify like parts.

Each tile 11 may comprise a configuration similar to that shown in FIG. 3 wherein side edges 14' are contiguous and form a square, said edges being interrupted by recesses 16 each having a recess face 17, recess side walls 18 and end wall 19'. Each tile 11' includes a front face 12 and a back face 15, the front and back faces lying in parallel planes and the tile being arranged in horizontal and vertical parallel rows or courses. In such arrangement the recesses 16 are aligned and receive rigid metallic interconnecting elements 72.

Metallic element 72 may be rectangular in shape and has a width only slightly less than the width of recesses 16 and a length only slightly less than the distance between opposed recess end walls 19. Metallic element 72 has a thickness lightly less than the depth of recess 16 so that when a rigid metal element 72 is positioned in a pair of opposed recesses 16 the back face 73 will lie in the same plane as the plane of the back face 15' of the tile.

Rigid element 72 thus extends across joint space 75 defined by opposed side edges 14 and abutment of end edge faces 76 of element 72 with recess end walls 19 serves to establish the width of joint 75. The side edges 77 of element 72 relatively closely fit between the recess side walls 18 and thus serve to align adjacent tile about the long axis of the rectangular element 72. Since the long axes of elements 72 are disposed both vertical and horizontal or at right angles to each other with respect to adjacent sides of tile it will be apparent that elements 72 and recesses 16 cooperate to align tile both vertically and horizontally. Moreover, when elements 72 are seated against the flat recess faces 17 such seating relationship establishes and tends to position adjacent tile in the same plane.

As in the prior modifications the elements 72 may be bonded to the tile in said recesses with a suitable adhesive or bonding material such as the epoxy bonding means heretofore described.

In addition to the interconnecting and bonding of the tile together by such an adhesive means and elements 72 further bonding of the discrete separate tiles into an assembly which may be readily handled may comprise the use of a joint filling material 79 which preferably will include an epoxy type adhesive. The material 79 thus bonds the opposed side edges 14' of the tile together as well as completing the panel unit so that it may be installed as a unit on a selected supporting wall surface.

As in the prior modifications the assembly of such a panel 10 may be made in a jig and the units in the discrete tile precisely and accurately aligned and held in such alignment while the metal elements 72 are being firmly bonded to the back faces of the tile upon curing and final setting of the adhesive means. The joint filling material 79 will also be setting during this period. It will be understood by those skilled in the art that the coaction of the discrete tile 11' the discrete elements 72 and the edge bonding means 79 structurally join together the plurality of tile so as to provide a rigid panelized assembly having a thickness substantially that of the thickness of the tile and in which the discrete tile are interlocked and held together by the metal elements 72 in precise alignmeat.

It will be readily understood by those skilled in the art that various other modifications and changes may be made in the method and means for forming a unifying panel construction, and all such changes and modifications which come within the scope of the appended claims are embraced thereby.

I claim:

1. A unifying construction whereby a multiplicity of discrete tile are cooperatively combined into an integrated readily handleable article of enhanced utility and appearance, comprising:

a plurality of discrete tile each having a front face, a

bonded to the recessed surfaces. by .a cementing.

material and the abutting contact of the surfaces of said metal elements with the surfaces of said tile being the sole means for precisely positioning said tile in said aligned relation; and

a preformed, resilient, longitudinally grooved joint filling member carried by said medial leg and sealing,

the space between said spaced edges of tile. 2. A readily handleable integrated panel unit including a multiplicity of discrete tile, each having a porous rear face, cooperatively combined in aligned relation with such rear faces in a common plane, said panel unit beingv adapted to be readily set in bonding cement in adjoining and aligned relation with other such integrated panel units, comprising:

a multiplicity of discrete tile, each having a front face, a rear face, and side edges, the rear face of each tile being porous and including a recessed surface starting at each side edge; the multiplicity of said tile being arranged with their edges in aligned spaced relation and with their rear faces in a common plane; elongated, individually rigid metallic elements having portions of T-section, said elements including a medial leg extending between spaced edges of adjacent tile and oppositely directed lips extending into opposing recesses in the rear faces of such adjacent tile, and a cementing material firmly bonding said lips to the recessed surfaces, such bond and contact between said elements and the tile surfaces being the sole means for maintaining the multiplicity of tile inan integrated handleable unit having a planar back face, the porous rear faces of the tile in said unit lying in a common plane and being adapted for bonding with a cementitious bedding material, the outer edges of tile in saidunit being adapted for abutment and connection with another unit. 3. A readily handleable integrated panel unit including a multiplicity of discrete tile, each having a porous rear face, cooperatively combined in aligned relation with such rear faces in a common plane, said panel unit being adapted to be readily set in bonding cement in adjoining and aligned relation with other such integrated panel units, comprising:

a multiplicity of discrete tile, each having a front face, a rear face, and side edges, the rear face of each tile being porous and including a recessed surface starting at each side edge; the multiplicity of said tile being arranged with their edges in aligned spaced relation and with their rear faces in a common plane; elongated, individually rigid metallic elements having portions of T-section, said elements including a medial leg extending between spaced edges of adjacent tile and oppositely directed lips extending into opposing recesses in the rear faces of such adjacent 8., tile, grout-like means contacting said medial leg and opposing spaced edges of adjacent tile and a cementing material firmly bonding said lips to the recessed surfaces, such bond andcontact between saidelements and tile surfaces being the sole means for maintaining the multiplicity of tile in an integrated handleable unit having a planar back face, the porous rear faces of the-tile in. said unit lying in a common plane and being adapted for bonding with a cementitious bedding material, the outer edges of tile in said unit being adapted for abutment and connection with another unit.

4. A panel unit as stated in claim 3 wherein said oppositely directed lips are perforated.

5. A readily handleable integrated panel unit including a multiplicity of discrete tile, each having a porous rear face, cooperatively combined in aligned relation with such rear faces in a common plane, said panel unit being adapted to be readily set in bondingcement in adjoining and aligned relation with other such integrated; panel units, comprising:

a multiplicity of discrete tile each: having-a front face, a rear face and side edges, the rear face of each tile being porous and including a recess starting-at each side edge and defined by-recess side walls, arecess end walland- H =I6C6SS,- surface parallel to'the rear face; the multiplicityof said tile, being arranged with their edges in aligned, spaced relation and with'their rear faces. in a common plane;

a plurality of individually rigid 'metallicmembers each having flat portionspositioned in opposed recesses of adjacent tile, said flat portions having; edges adapted to cooperate with side andend walls of recesses to align and space the tile with'respect to each other; and a cementing material firmly bonding said flat portions to the recessed surfaces, said rigid members, said recesses and cementing material maintaining the multiplicity of tile with edges of such tile in alignment in the form of anintegratedhandleable unit having a planar backface composed of porousback facesof tile ina common plane and adapted for bonding with. a cementitious bedding material, the outer edge portions of tile in said unit being adapted for abutment and connection with another unit.

6; A readily handleable integrated panel unit as stated in claim S whereineach of said recesses isat a predetermined zone along the edge of a tile.

References Cited by the Examiner UNITED STATES PATENTS 687,501 3/1901' Held 50-405'X 1,807,630 6/1931 McFarlin 52391 1,997,092 4/1935 Duify 52502 2,073,130 3/ 1937 Wallace 52396 2,198,450 4/1940 Chertkof 52200 2,672,106 3/1954 Lenke 52442 2,708,016, 5/1955 Penton' 52396 2,852,932 9/1958 Cable 52385 2,986,848 6/1961 Greene 52396 FOREIGN PATENTS 589,804 7/ 1947 Great Britain. 613,982 9/1926 France. 884,781 5/1943 France. 1,187,185 3/1959 France.

97,119 10/1939 Sweden.

FRANK L. ABBOTT, Primary Examiner.

HENRY C SUTHERLAND, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,234,692 February 15, 1966 Knud Georg Bierlich It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the grant, line 1, for "Knud Georg, of Bierlich,

Los Angeles," read Knud Georg Bierlich, of Los Angeles, in the heading to the printed specification, line 3, for "Knud Georg, Bierlich, Los Ange les," read Knud Georg Bierlic Los Angeles,

Signed and sealed this 31st day of January 1967.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNE] Attesting Officer Commissioner of Patents

Claims

1. A UNIFYING CONSTRUCTION WHEREBY A MULTIPLICITY OF DISCRETE TILE ARE COOPERATIVELY COMBINED INTO AN INTEGRATED READILY HANDLEABLE ARTICLE OF ENHANCED UTILITY AND APPEARANCE, COMPRISING: A PLURALITY OF DISCRETE TILE EACH HAVING A FRONT FACE, A REAR FACE AND SIDE EDGES, THE REAR FACE OF EACH TILE INCLUDING A RECESSED SURFACE STARTING AT A SIDE EDGE; A MULTIPLICITY OF SUCH DISCRETE TILE BEING ARRANGED WITH THEIR EDGES IN ALIGNED SPACED RELATION AND WITH THEIR BACK FACES IN A COMMON PLANE; AND ELONGATED, INDIVIDUALLY RIGID METALLIC ELEMENTS OF T SECTION HAVING THEIR OPPOSITELY DIRECTED LIPS EXTENDING INTO OPPOSING RECESSES OF ADJACENT TILE AND THEIR MEDIAL LEG EXTENDING BETWEEN THE SPACED EDGES OF ADJACENT TILE, SAID METALLIC ELEMENTS BEING FIRMLY BONDED TO THE RECESSED SURFACES BY A CEMENTING MATERIAL AND THE ABUTTING CONTACT OF THE SURFACES OF SAID METAL ELEMENTS WITH THE SURFACES OF SAID TILE BEING THE SOLE MEANS FOR PRECISELY POSITIONING SAID TILE IN SAID ALIGNED RELATION; AND A PREFORMED, RESILIENT, LONGITUDINALLY GROOVED JOINT FILLING MEMBER CARRIED BY SAID MEDIAL LEG AND SEALING THE SPACE BETWEEN SAID SPACED EDGES OF TILE.