Wack, Henry P. (Souderton, PA)
Claus, Karl M. (Hatfield, PA)

05/236429

06/18/1974

03/20/1972

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American Olean Tile Company, Inc. (Lansdale, PA)

52/315

52/35, 428/49, 52/389, 52/385

E04F13/08; E04F19/06; E04F19/02; E04F13/14

52/35,315,389,385,388,39X

3131514	Thin precast wall panel construction	May 1964	Siek
3203144	Laminar geodesic dome	August 1965	Fuller
3362119	Tile building panel with plastic foam backing	January 1968	Murphy
3420021	KNOCK-DOWN SHOWER UNIT ENCLOSURE	January 1969	Anghinetti
3502539	LAMINATED PRODUCT AND PROCESS	March 1970	MacPhal
3646180		February 1972	Winnick
3646715	PREFABRICATED BUILDING PANEL	March 1972	Pope

Abbott, Frank L.

Raduazo H. E.

Howson, And Howson

This application is a continuation-in-part of our co-pending application Ser. No. 72,357, filed Sept. 15, 1970, now abandoned.

We claim

1. A lightweight prefabricated ceramic tile construction panel comprising a pregrouted tile sheet, a foam backer and a paper backing sheet, said tile sheet comprising a plurality of ceramic tile elements geometrically arranged to form a planar array, the edges of each said tile and having a beveled portion adjacent the front face thereof and a non-beveled portion adjacent the rear face thereof, the non-beveled portion of each said tile edge comprising a planar surface perpendicular to said rear face, the beveled portion of each said tile edge comprising a substantially planar surface intersecting said non-beveled portion surface and extending inwardly at an acute angle therefrom to intersect said tile element front face, the edges of adjacent tile elements abutting along the full length of their nonbeveled edge portions, elastomeric grouting disposed between and bonding the beveled edge portions of adjacent tile elements, said foam backer comprising a layer of rigid closed-cell plastic foam bonded to the rear face of said planar array of tile elements by a foamed in situ bond, said paper backing sheet being bonded to the rear surface of said foam backer by a foamed in situ bond.

2. The invention as claimed in claim 1 wherein said paper backing sheet comprises a fiber-reinforced paper sheet.

3. The invention as claimed in claim 1 wherein said plastic foam backer comprises a closed-cell polyurethane foam.

4. The invention as claimed in claim 1 wherein said beveled portion of each tile edge comprises substantially two thirds of the thickness of the tile, and wherein said non-beveled portion comprises substantially one third of the thickness of the tile.

5. The invention as claimed in claim 1 wherein said tile elements have a rectangular configuration.

6. The invention as claimed in claim 1 wherein said tile elements have a square configuration.

The present invention relates generally to prefabricated ceramic tile panels and more specifically to a novel light weight, ceramic tile panel and mounting arrangement therefore which can be quickly applied by those unskilled in the art of tile setting.

The advantages of ceramic tile walls and floors especially for bathrooms, shower rooms, kitchens and the like are well known. The setting of tiles at a construction site is, however, a painstaking and time consuming task which, utilizing conventional construction methods, requires substantial preparation steps by professional craftsmen to assure a sound and true surface upon which the tiles can be set. With the present high labor costs in the building trades and the accelerated rate of construction schedules, the traditional methods of installing ceramic tile are extremely costly and time consuming.

The recent trend toward modular housing construction wherein housing sections are factory built and joined together at the construction site has further spotlighted the shortcomings of the conventional tile installation methods. Since the modular units are built in a production line manner similar to those employed for automobile assembly, there is not sufficient time for employment of conventional tile setting techniques. Instead, substitutes such as Fiberglas panels have been utilized despite the recognition that such substitutes are functionally and aesthetically inferior to the traditional ceramic tile surfaces.

In the conventional construction of ceramic tile walls, for example bathroom walls, it is recommended that the following steps be taken to provide a suitable base for the tile on the usual wood stud support structure. First a moisture barrier of felt or polyethylene film is placed over the studding to prevent moisture penetration to the wood studs. Next, metal lathing is secured to the studs and a mortar scratch coat is applied to the lath. Subsequently, a mortar bed is applied over the scratch coat and accurately leveled to provide a true surface for setting of the tile. If the scratch coat should be uneven due to irregularities in the studding for example, a separate leveling coat may be required. Finally, when the previous coats are sufficiently set and cured, the ceramic tile is set in tile cement, a task requiring the services of an experienced tile setter. Grout is then applied between the tile elements, and, where the tile edges are adjacent to fixtures such as tub edges, a suitable elastomeric caulking is applied. The entire operation usually takes at least several days to complete and requires the services of carpenters and plasterers in addition to the tile setters.

Various developments have to a degree reduced the tile setter's task. For example, tiles are commonly prepared in sheets secured by back mounted means, thus eliminating the need to properly position each individual tile. More recently, elastomeric grouting materials have been developed which have permitted the fabrication of pre-grouted tile sheets. In each case, however, it is still necessary to prepare a true and stable surface, normally a mortar bed, on which the tiles are cemented.

The concept of a prefabricated tile panel which would not require any tile setting at the installation site nor the preparation of a tile bed has long been considered but until the present invention has not been effectively developed. Early efforts toward implementing this concept included the suggested mounting of ceramic tile on a slate backing slab. This would result in a heavy, relatively fragile panel that would be difficult to install, and which would require special handling and transporting techniques. Later approaches suggested the mounting of tiles on various other laminar panel elements such as plywood and gypsum board. These approaches have similarly proved unsatisfactory for such reasons as insufficient rigidity, susceptibility to moisture penetration, dimensional stability, excess weight, etc.

Accordingly, despite the long felt need evidenced by the many attempts to develop an acceptable panel, a suitable prefabricated tile panel has not for a variety of reasons been developed prior to the present invention. Although there are inherent factors which could hinder the commercial acceptance of such panels such as the need for accurately dimensioning the panels during fabrication and the problems involved in transportation and storage of the bulky and somewhat fragile panels, the structural characteristics and the difficulty of installation of the previously suggested panels have been the principal factors precluding their acceptance. Characteristics to be considered, for example, include the sound and moisture insulating properties of the panels, particularly in the case of bathroom walls. The panels must be sufficiently rigid to permit handling during installation and to provide the structure integrity required for installation over studs. Furthermore, the panel weight is a limiting factor, both as it affects the difficulty of installation and as it requires suitable supporting members. Another significant factor is the compatability of the tile panel edges with the adjacent wall structure. Consideration must also be given to the flammability of the panel components, heat insulating properties, dimensional stability, etc.

The present prefabricated ceramic tile panel is formed of a pre-grouted tile sheet and a backer of closed cell plastic foam. The backer is foamed in place on the tile sheet to provide a panel sufficiently rigid for mounting directly on open studding in the novel manner described below. Tests have proven the foam board to be sufficiently rigid in fact, to permit the reduction of the thickness of the tile to provide an extremely light weight panel, wall-sized sections of which can be easily handled and installed by one man. The addition of a fiber-reinforced sheet to the rear surface of the foam backer further strengthens the panel and permits the use of a relatively thin foam layer.

With the present invention, the conventional tedious and time consuming tile setting operations are completely eliminated and the novel prefabricated tile panels may be mounted directly on open studding by those unskilled in tile installation. The installation, instead of requiring days of various types of labor, requires only minutes of a worker's time, and the quality of the tiled surface is superior to that obtainable by a tile setter working at the site. The manufacture of prefabricated, pre-grouted tile panels of a size sufficient to cover an entire wall of a typical bathroom and which is sufficiently rigid, moisture and sound proof to permit mounting directly to the studding allows the construction of the tiled walls to proceed at a pace consistent with that of the surrounding construction.

It is accordingly a first object of the present invention to provide a prefabricated pre-grouted ceramic tile panel of a rigid light weight construction which is moisture proof and which has superior sound and thermal insulating characteristics.

A further object of the invention is to provide a prefabricated panel as described which may be applied directly to open wall studding.

Another object of the invention is to provide a prefabricated tile panel as described which may be installed by those unskilled in tile setting techniques.

An additional object of the invention is to provide a tile panel as described which is flame retardant or self-extinguishing.

Still another object of the invention is to provide a prefabricated panel as described which is compatible with surrounding wall construction.

A still further object of the invention is to provide a mounting system for a prefabricated tile panel as described which permits the installation of a plurality of panels in proper alignment and registration in a few minutes time.

Additional objects and advantages of the invention will be more readily apparent from the following detailed description of embodiments thereof when taken together with the accompanying drawings in which:

FIG. 1 is a perspective elevational view illustrating the present panel system as installed to form a tub surround, the panels being broken away and one end panel being moved out from its mounted position to reveal the details of the panel supporting structure;

FIG. 2 is an enlarged view partly in section taken along line 2--2 of FIG. 1 showing details of the lower panel edge mounting arrangement;

FIG. 3 is a sectional view taken along line 3--3 of FIG. 2;

FIG. 4 is a face view of a panel similar to the right hand panel of the tub surround shown in FIG. 1 but including a fiber-reinforced paper sheet on the rear face of the foam layer;

FIG. 5 is an enlarged sectional view taken along line 5--5 of FIG. 4;

FIG. 6 is an enlarged sectional view taken along line 6--6 of FIG. 4;

FIG. 7 is an enlarged rear perspective view of a portion of the tile panel shown in FIGS. 4-6 with the paper sheet folded back to show the fiber reinforcement thereof;

FIG. 8 is a perspective view of the part of the panel fastening means which is secured to the tile panels;

FIG. 9 is an exploded perspective view of the tile panel support strips which are affixed to the wall studs prior to installation of the panel;

FIG. 10 is a sectional view taken transversely through one of the installed panel support strips and showing a spacing finger attached thereto for positioning the strip above the edge of a tub;

FIG. 11 is a perspective view showing one of the spacing fingers detached from the supporting strip;

FIG. 12 is a face view showing a plurality of edge-abutted panels which are installed and joined using the novel panel mounting system of the present invention;

FIG. 13 is a sectional view taken along line 13--13 of FIG. 12;

FIG. 14 is a sectional view taken along line 14--14 of FIG. 12;

FIG. 15 is an interrupted perspective view of a tile panel edge securing strip;

FIG. 16 is a face view showing the joining of a pair of panels by a strip of the type shown in FIG. 15 and utilizing a modified form of the strip to secure the upper panel edges;

FIG. 17 is a sectional view taken along line 17-17 of FIG. 16; and

FIG. 18 is a sectional view showing a modified form of the panel wherein the tile edges have a modified configuration.

Referring to the drawings, and particularly FIG. 1 thereof, an installation of prefabricated, pre-grouted ceramic tile panels in accordance with the present invention is illustrated for making a tub surround in one end of or as an alcove of a bathroom. A standard metal tub 20 is secured in place in the conventional close fitting relation to the wooden studs 22 which frame the three tub surrounding walls. The tub installation and the construction of the studding is basically conventional.

As illustrated in FIG. 1, each tiled wall of the tub surround is formed of a single prefabricated, pre-grouted tile panel. The end wall panels 24 and 26 along their inner side edges cooperatively fit into corner assemblies 28 which similarly engage the side wall panel 30 in a manner permitting the erection and securing of the panels to the studding in a few minutes time. The light weight of the panels permits even the large side wall panel 30 to be lifted into place and installed by one man.

The construction of the tile panels is exemplified by the detailed views of end panel 26 shown in FIGS. 2 and 3. The panels consist essentially of a geometrical array of ceramic tile elements 32, in this instance of a 4 inches square size, which are secured in spaced relation to a plastic foam backer 34. A preferred material for the foam backer is polyurethane, although other plastic foam materials may also be used as discussed below. The joints between the tile elements are grouted with an elastomeric grout 36 which will not crack or part should the panel be subjected to rough handling during transport or installation.

Although the combination of the plastic foam backer and the pre-grouted tile sheet is a relatively simple structure, the functional advantages flowing from the combination overcome virtually all of the problems plaguing the prior attempts to develop an acceptable ceramic tile panel. Of primary importance, the combination is unexpectedly rigid, in fact to such a degree as to permit the reduction in tile thickness from the conventional five-sixteenths inch to approximately three-sixteenth inch, thereby eliminating as much as 33 percent of the usual weight of the tile elements. With a foam thickness of approximately one-half inch, the panel is sufficiently rigid to permit its mounting directly over the bare studding as shown in FIG. 1, with the studs spaced the conventional 16 inches on centers.

To a significant degree, the rigidity of the panels is provided by the "skin effect" rear surface of the foam backer which is characteristic of a foamed-in-place sheet. The rear surface "skin" is a thin, harder exterior layer of the foam, the outer surface of which will assume a smooth polished condition if the mold surface employed to form the sheet is of that character.

The tile-plastic foam panel is especially suited for use around showers and tubs because of its moisture impenetrability. The ceramic tile itself is of course impervious to water as is the elastomeric grout. In the unlikely event that moisture should pass through to the foam backer, the water is blocked by the foam which is not in any way effected by or given to passage of moisture. The sound and heat insulating properties as well as the dimensional stability of the panels is excellent. The ceramic tile is, of course, non-flammable, while most plastic foam can readily be made fire retardant or self-extinguishing by the addition of small quantities of additives to the polymer phase.

The extreme light weight of the present panels permits entire wall-sized units to be prefabricated. An important part of the present invention is the novel mounting arrangement and method of installation whereby the panels may be installed within a few minutes time by those unskilled in tile installation techniques. The present mounting arrangement will be described in conjunction with the three tile panels 24, 26 and 30 forming the tub surround shown in FIG. 1.

Panel support means generally designated 38 are attached to the studs 22 and comprise horizontal panel support strips which are nailed or otherwise secured to the studs. For the tub surround installation, as shown in FIGS. 9-11, a pair of support strips 40 and 42 are provided along the side panel studs, the strips being formed of sheet metal and having respective arm portions 40a and 42a extending perpendicularly at opposed ends. A tongue portion 44 of the strip 42 is adapted to adjustably slide into the bracket 46 formed in the strip 40 to insure alignment of the strips. End panel support strips 48 and 50 similarly include tongue portions 52 and 54 respectively which are adapted to slidable positioning within brackets 56 and 58 of the side wall strips. Each of the strips includes a V configured lower edge portion 60 upon which the panels are supported.

Spacing fingers 62 are provided at spaced locations along the support strips as shown in FIG. 1 to accurately position the support strips at a predetermined distance above and parallel to the upper face 64 of the tub 20. The fingers 62 include a V shaped upper edge 66 adapted to cooperate with the V shaped support strip lower edges, and a tab 68 which holds the finger on the support strip in vertically depending slidable relation thereto. The fingers 62 extend downwardly from the outer edge of the support strip V edges and hence clear the upstanding tub rim 70.

As shown in FIG. 4, the lower edge 72 of each tile panel foam backer has an inverted V configuration adapted to cooperatively engage the V configured edges 60 of the panel strips. The lower edge of the bottom row of tile elements extends substantially below the backer edge 72 and thus covers the panel support strip and fingers when the panel is positioned thereupon. It will be apparent that since the support strips are accurately leveled and aligned with the tub, the tile panels will when placed thereon also be accurately leveled and aligned.

The corner assemblies 28 as shown in FIGS. 1 and 3 include a plurality of cover shaped tile elements 74 having the same height and vertical spacing as the tile panel tile elements. The cover elements 74 are bonded to a foam backer 76 by foaming the backer in place on the pre-grouted cover elements to produce a rigid corner assembly having the same height as the tile panels. Slots 78 are provided in the corner assemblies behind the side edges of the cover elements and are adapted to receive the projecting tile edges of the tile panels as most readily seen in FIG. 3. The slots 78 are as illustrated somewhat deeper than necessary to accommodate slight inaccuracies in the stud locations, tub leveling, etc. For the same reason, the tile edges of the panels project beyond the backers a sufficient amount to provide some spacing between the backers and the corner assembly backer as shown at 80 in FIG. 3. It should be noted that the horizontal grout lines 82 of the corner assemblies exactly match the corresponding grout lines of the adjacent panels, and the accommodation provided in installation by the slots 78 will not affect this aesthetically desirable relationship.

The panels 24, 26 and 30 as well as the corner assemblies 28 are adhesively secured to the studs 22 by the use of a conventional stud adhesive as shown for example in FIGS. 2 and 3. Although the stud adhesive when cured in conjunction with the support strips 38 provides a permanent attachment of the panels to the studding, it is necessary to temporarily secure the panels in place while the stud adhesive is curing. This is most conveniently done by use of the snap fastening means 84 illustrated in FIGS. 6-8. A sheet metal tab 86 is pointed at one end for insertion into the tile panel foam backer adjacent and parallel to the tile elements. The tab includes a channelshaped opposite end 88 on the rear facing surface of which is mounted one part 90 of a commercially available snap fastener sold under the name "Hedlock" by 3M Company, St. Paul, Minn. The second part 92 of the snap fastener is secured directly to the studs 22 as shown in FIG. 1. Since the tile elements project beyond the foam back along all of the edges of the panel, the snap fastening means may readily be located at spaced positions along the outer side edges of the end panels and along the top edges of all three panels to temporarily secure the panels against the studs while the stud adhesive sets up. Although unneeded after curing of the adhesive, the snap fasteners are left in place and serve to doubly secure the panels in position.

The method of installation of the tub surround shown in FIG. 1 comprises the following steps. First, the studding 22 is erected in the usual close fitted relation to the tub edges. The tub is leveled and secured to the studding by means of hanger assemblies in a conventional manner. The panel support strips are then accurately positioned on and nailed to the studding, the strips being respectively aligned with each other and properly spaced above the tub by the cooperating tongues and brackets, and the fingers 62. The snap fastener elements are then secured in the proper relationship on the studs and tile panels as illustrated in FIG. 1. The stud adhesive 94 is next applied to the faces of the studding which will contact the rear faces of the tile panels and the corner assemblies. The side panel 30 with the corner assemblies positioned on each end edge is then set in place on its supporting strips 40 and 42 and is firmly pressed into position against the studs to secure the snap fasteners and spread the stud adhesive. The end panels 24 and 26 are then similarly installed by inserting the inner side edge tiles into the corner assembly grooves, lowering the panels onto the supporting strips, and firmly pressing against the studs to seat the snap fasteners and set the adhesive.

The tile installation is completed by applying an elastomeric grout such as a silicone grout 96 between the lower edges of the tile and the tub as shown in FIG. 2. Similarly, elastomeric grout is applied at 98 along each side edge of the corner assembly cover elements, and at 100 along the end panel outer side edges where the projecting tiles may, for example, overlap a dry wall panel 102 as shown in FIGS. 1 and 3.

A modified form of the tile panel is illustrated in FIGS. 4-7 wherein an end panel 24' is shown having spaced tile elements 32', elastomeric grouting 36' therebetween, and a foamed-in-place backer 34'. In these respects the panel 24' is identical to those panels previously described. The panel 24' differs only in the inclusion of a fiber-reinforced Kraft paper sheet 104 on the rear face of the foam layer which is secured thereto by foaming the foam layer in place against both the tile elements and the paper sheet 104.

The inclusion of the reinforced paper sheet produces a sandwich effect and serves to strengthen the panel so that the thickness of the foam layer can be reduced and still produce a panel having sufficient rigidity for mounting directly upon open studding. In the embodiment illustrated in FIG. 7, the Kraft paper sheet 104 is reinforced by a glass fiber scrim 106 which is affixed to the inner side of the paper by a thin polyethylene coating. The heat generated by the foaming-in-place of the foam layer melts the polyethylene coating and allows the reinforcing fibers and paper to become directly bonded to the foam layer, thus forming a substantially stronger "skin effect" than that naturally produced by the foaming-in-place process. The corner assemblies as shown in FIG. 3 may also be strengthened by the use of a fiber reinforced paper backing sheet 106 bonded around the rear surface of the foam layer by foaming-in-place.

To join the present panels in edge-abutting planar relation, for example for tiling the walls of school or hospital corridors, a novel panel edge securing system is shown in FIGS. 12-17. In this system the tile panels 110 are nearly identical to those shown in FIG. 1 and include tile elements 32, foam backers 34, and elastomeric grouting 36. V-configured support strips 112 nailed to a wall studding 114 in spaced relation above the floor 118 support the panels in the same manner as described above.

The panels 110 differ in that the top and side panel edges are characterized by only a slight projection of the tile edges beyond the foam backers as shown in FIG. 14. A tile edge securing strip 120 as shown in FIG. 15 is cooperatively disposed between adjoining tile panel edges (FIG. 14) to hold the edges in planar relation. The strip 120 includes a base portion 122 adapted for nailing to studding or a wall, an upstanding web portion 124, and panel securing teeth 126 extending from the web portion parallel to the base portion which are adapted to extend into the panel foam backers adjacent the tiles in the same manner as the snap fastener means 84 described above. To secure the top or side edges of a panel which does not adjoin another panel, the modified securing strip 128 of FIGS. 16 and 17 may be employed which has a base portion and teeth extending in only one direction from the web.

The installation of the system of FIGS. 12-17 is quite similar to that described above with respect to the tub surround. The supporting strips 112 are first nailed in spaced relation to the floor, and stud adhesive is then applied to the studding. A first panel is then placed on the support strips and the edge securing strips 120 are driven into the panel edges to be adjoined by adjacent panels. The protruding portions of the securing strips are then nailed to the studding to anchor the edges and permit setting of the stud adhesive. Successive panels are mounted in the same manner, except that the panels are first driven into the already nailed securing strips of the preceding panels. Strips 128 are employed as the non-abutting vertical and horizontal panel edges. Elastomeric grouting 130 is applied at the floor edge of the tile panels and similarly at 132 between abutted panels.

In FIG. 18 a further modified form of tile panel is illustrated in section. In this embodiment, the panel 140 comprises tile elements 142, elastomeric grouting 144, foamed in place foam layer 146, and fiber reinforced Kraft paper backing sheet in much the same relationship as that of the embodiment of FIGS. 4-7. However, the tile edges are beveled from the tile faces, and the tiles are assembled in edge abutting relation, the edges being in engagement over about one-third the thickness of the tile. The elastomeric grouting then fills the beveled gap between the tile faces and the appearance of the panel is identical with the embodiments described above. This modified tile edge panel is somewhat more rigid than the above embodiment due to the engagement of substantial portions of the tile edges.

The plastic foam backer should be of the rigid closed cell type and as indicated above is preferably a polyurethane foam. The preferred foam density using polyurethane foam is approximately 4 pounds per cubic foot which provides the desired panel stiffness. Although the foam selected should have a sufficiently high density to provide the necessary panel strength, extremely high density foamed plastics should be avoided since they tend to be rather brittle and in addition add unnecessary weight to the panel. A certain minimal flexibility of the panels is desirable to prevent panel breakage during shipment and installation and is permissible in view of the use of an elastomeric grout between the tile elements which will not crack with panel flexure. Although polyurethane, polyvinylchloride, and polystyrene are the principal commercially available products which could be used for the panel foam backer, other suitable rigid plastic foam materials can also be used to practice the invention.

The light weight of the plastic foams combined with their high strength, excellent insulating properties, moisture impenetrability and fire retardant capabilities are characteristics which contribute to the exceptional suitability of rigid closed cell plastic foam for the tile panel backer. The foam chosen for the panel should include the proper additives to make the foam fire retardant or self-extinguishing.

The elastomeric grout and the stud adhesive are commercially available products. An example of a suitable elastomeric grout is that sold under the name Dow 780 by Dow Corning Corp., Midland, Mich. 48640. A suitable stud adhesive is that sold by the Franklin Glue Co., Columbus, Ohio 43207 named "Franklin Construction Adhesive".

Elastomeric grouting is difficult to apply in the field, thus increasing the price of an installation where specified. With the present invention, the elastomeric grouting is machine applied in the factory where it can be easily and inexpensively applied by specially trained personnel. The elastomeric grouting plays an important role in the panel fabrication since it permits the complete pre-grouting of the panel with a material which won't crack under the strains of shipment and installation and which is completely waterproof.

Although the panel support strips and the cooperating portion of the panels are illustrated in a V groove configuration, it will be apparent that other types of cooperating configurations could be used such for example as tongue and groove, and similar well known aligning joints. It will also be apparent that the size and shape of the tile elements is not critical and that the invention could suitably be used with smaller or larger tile sizes.

Although the installation illustrated shows the panels mounted directly on open studding, it is obvious that the panels could also be mounted directly to any type of wall surface such as a plaster, wood or masonry wall. It is thus anticipated that the present panel will enjoy widespread usage in the renovation of older structures wherein the cost of removing existing walls and laying a mortar base for conventional tile installation would be prohibitive.

As indicated above, the strength and rigidity of the foam is sufficient to permit a reduction in thickness of the tiles which results in a corresponding reduction in the weight of the tiles. As a result, the weight of a tile panel using ceramic tile having a thickness of approximately three-sixteenths inch and a polyurethane foam one-half inch thick and having a density of approximately 4 pounds per cubic foot is only 2.2 pounds per square foot. Since the weight of conventional five-sixteenths inch tile alone is 3.2 pounds per square foot, it can be understood that the present construction provides a rather striking reduction in the overall weight of a tiled wall. This is especially true when contrasted with conventional mortar construction which is estimated to weigh 18 pounds per square foot.

Considering the tub surround shown in FIG. 1, in an actual installation the side wall panel 30 having a conventional length of 60 inches and a height of 60 inches weighed only about 67 pounds. The smaller end wall panels 24 and 26 which measure 28 inches by 60 inches each weighed approximately 32 pounds. Accordingly, each of the tile panels may be easily moved into place by one man without undue difficulty. The light weight further minimizes the cost of shipment and facilitates handling during all phases of manufacture, transport and installation. The light panel weight is especially important in the construction of mobile homes or modular homes which are factory built and shipped to their ultimate site.

The preferred backing sheet material is a fiberreinforced Kraft paper which has proven particularly durable in impact tests. However, other types of reinforced sheets such as fiber-reinforced plastic shets may also prove suitable to provide the desired "skin effect" at the rear face of the panel.

The bonding of the foam layer to the tile elements and the backing sheet by foaming in place, also known as foaming in situ, provides a strong bonding attachment of the foam to the tiles and backing sheet. The tiles need not be serrated on their back faces and in the preferred embodiment have a smooth planar back surface. A primary advantage of the foamed in place construction, as indicated above, is the "skin effect" formation, particularly in the embodiment without the backing sheet. The foaming in place operation is, of course, carried out during the factory manufacture of the panel and is most readily accomplished in a horizontal mold with the pre-grouted tile sheet disposed face down in the mold. The foam producing materials are then poured onto the tile sheet prior to closing of the mold.

Manifestly, changes in details of construction can be effected by those skilled in the art without departing from the spirit and the scope of the invention.