CA1179453A - Hot tub construction - Google Patents

Abstract

HOT TUB CONSTRUCTION

ABSTRACT OF THE DISCLOSURE

A kit for use in converting a not-necessarily-watertight tub or other enclosure into a hot tub includes a number of rigid unitary shell-like plastic seat segments that are coupled together in juxtaposition to form a bench-like seat extending around the wall inside the tub, and-also includes a pliable waterproof plastic liner that covers the bench-like seat and the part of the floor not covered by the seat and extends up the wall above the bench-like seat to retain the water in the hot tub. A pliable resilient sheet of closed-cell plastic foam interposed between the waterproof plastic liner and certain portions of the wall, floor and seats enhances heat retention in the hot tub and imparts a comfortable resilient feel to the exposed sur-faces. The seat segments are shaped to nest for storage and shipping.

Description

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3 BACKGROUND OF THE IN~NTIO~
4 Field of the Invention The present invention is in the field of hot tubs 6 and spas and specifically relates to an imProved con-7 struction for such structures.

9 The Prior Art Hot tubs and spas have enjoyed a surge of popularity 11 in recent years as their healthful and recreational benefits 12 have become more widely appreciated. Concurrently with this 13 surge in popularity have come a number of recent improvements 1~ in the structure of the hot tub. Because of these recent improvements, the contemporary hot tub is quite superior to 16 the traditional wooden hot tub in cleanliness, freedom from 17 leakage, modes of operation, and economy of operation.
18 Because of the newness of the improvements, the 9 relevant prior art is found in the contemporary literature 20 of the field, including trade publications. A more detailed 21 discussion of thè prior art is given in the ~rior Art State-22 ment filed concurrently with the present application.
23 The hot tub shown in Figure 1 is exemplary of the 24 recent prior art. A rigid one-piece liner 2 of plastic 25 or fiberglass is provided, which sits within the wooden tub 10.
26 Some of the plumbing 4 is included in the space between the 27 liner 2 and the tub 10. A rigid plastic foam 6 may also be 28 included between the rigid one-piece plastic liner 2 and the 29 tub 10. In some cases, a rigid plastic pipe-like bubbler 30 ring 8 rests on the seat portion of the rigid liner, while 31 in other cases, the bubbler is concealed beneath the rigid 32 plastic liner.

1 Clearly, a rigid plastic bubbler ring sltting on the

2 seat portion of the rigid liner is both unsightlv and

3 uncomfortable to the user. Further, locating the bubbler

4 ring beneath the rigid liner under the seat complicates the construction and occasionally results in leaks. However, 6 the major problems with the hot tub shown in Figure 1 result 7 from the use of a single one-piece rigid liner. From the 8 standpoint of user comfort, the rigid liner is not particularly 9 comfortable to lean against or to sit on. Similarly, the rigid liner is of little use in cushioning a fall.
11 If the one-piece rigid liner develops a crack, the 12 entire liner may have to be replaced. Such liners are more susceptible to developing cracks and chips because they are 14 bulky and awkward to handle. Typically, such rigid one-15 piece liners are too large to fit through the doors of a 16 house and hence can only be installed in a restricted 17 number of locations. Also, the bulky one-piece rigid liner 18 is expensive to crate and to ship.
19 As will be seen below, the hot tub construction of 20 the present invention overcomes the problems inherent in 21 the construction used in the prior art.

SU~RY OF THE INVENTION
26 The present invention includes a novel and 27 advantageous construction for a hot tub. In accordance 28 with the present invention, more than one shell-like seat 1 segments are coupled in juxtaposition to form a bench-like 2 seat, which is then covered by and rendered waterproof by a 3 pliable watertight liner. As used herein, the word pliable 4 means sufficiently flexible to permit repeated folding without damage. The pliable watertight liner thus permits the bench-like seat to be constructed of a number of segments, 7 without concern that the water will -leak through the cracks 8 between the segments. Numerous advantages result from this 9 construction, some of which were not readilv apparent at the outset.
11 The hot tub of the present invention is less expen-12 sive to produce because, unlike the traditional wooden tub, 13 the wooden tub used with the present invention does not have 14 to be watertight, and in some embodiments of the present 15 invention, the floor of the tub can be eliminated altogether.
16 Further, it is more economical to produce the smaller 17 sections rather than the large one-piece rigid liner used 18 in the prior art.
~9 The hot tub construction of the present invention 20 is also less expensive to ship, because the segments 21 individually are smaller than the large one-piece liner 22 shown in Figure i and also because the segments in the 23 present invention are designed to nest for shipping and 2~ storage.
The present invention is marketed in kit form, and 26 once the hot tub of the present invention has been shipped 27 in kit form to the point of installation, it is found that 28 installation is facilitated by the design of the present g~L5~

1 invention. Unlike the prior art construction of Figure 1, 2 the parts of the present invention will fit easily through ~ doors and can be erected on any adequate foundation.
4 Perhaps the most striking advantage of the hot tub of the present invention is that it can operate more economically than other hot tubs. The dead air space 7 beneath the seats serves both to insulate the water in the 8 tub as well as to displace as much as 30~ of the water, and 9 since less water is used, the water that is used can be 10 heated more quickly to a desired temperature.
11 In accordance with the present invention, the 12 segments that are joined to form the bench-like seat are 13 covered with a watertight pliable liner which holds the 14 water. In a preferred embodiment, the liner is formed of 15 sheet vinyl having a thickness of 18 mils. Such a liner, 16 unlike the rigid liner of the prior art hot tub shown in 17 Figure 1, will never chip or peel, and in the absence of 18 abuse, should last for years.
19 The use of the pliable sheet-like liner yields a 20 further advantage. A pliable sheet of closed cell plastic 21 foam is interposed between the liner and the tub wall in 22 a preferred embodiment of the present invention, and the 23 resiliency of this sheet of plastic foam imparts an a~reeable 24 cushioned resilient feel to the portions of the structure 25 that are covered by the pliable plastic liner. The use of 26 this resilient layer has the safety advantage that it 27 reduces slipping and cushions falls. Finally, the resilient ~1 ///

i3 1 plastic foam layer is an excellent thermal insulator, 2 retarding heat loss from the hot tub.
3 Still further advantages result from the 4 construction employed in the present invention. In the unlikely event one of the segments of the bench-like seat sustains damage, it is not necessary to replace the entire 7 liner structure as with the prior art hot tub shown in 8 Figure 1, but instead it is necessary to replace only the 9 damaged segment.
In accordance with a preferred embodiment of the 11 present invention, the pliable watertight liner includes a 12 blister-like bubbler plenum enclosed beneath a patch of 13 pliable sheet plastic that is bonded to the watertight 14 liner and that extends circumferentially around the hot 15 tub, being located in different embodiments either at the 16 rear of the seat or just below the front part of the seat, 17 or both. This blister-like bubbler plenum is much more 18 comfortable and unobtrusive than the rigid pipe-like ~las-tic 9 bubbler ring used in the prior art.
Finally, the simplified construction of the hot 21 tub of the present invention permits it to be retrofitted 22 into existing traditional wooden hot tubs, even by 23 unskilled persons.
24 The novel features which are believed to be 25 characteristic of the invention, together with further 26 objects and advantages thereof, will be better understood 27 from the following description considered in connection ~8 ///

1 with the accompanying drawings in whlch se~eral embodiments 2 of the invention are illustrated by way of example. It is 3 to be expressly understood, however, that the drawings are 4 for the purpose of illustration and description only and are not intended as a definition of the limits of the ~ invention.

g 0 BRIEF DESCRIPTION OF T~IE DRAWINGS
1~ Figure 1 is a perspective view, partially cut away 12 to show a hot tub construction of the prior art;
13 Figure 2 is a perspective view, partly cut away to 14 show the hot tub construction according to a preferred 15 embodiment of the present invention;
16 Figure 3 is a perspective vlew showing the u~per 17 surface of a seat segment in a preferred embodiment of the 18 present invention;
19 Figure 4 is a perspective view of the underside 20 of the seat segment of Figure 3;
21 Figure 5 is a perspective view of the upper 22 sur~ace of a seat segment in an alternative embodiment of the 23 present invention;
24 Figure 6 is a perspective view of the underside 25 of the seat segment of Figure 5;
26 Figure 7 is a cross-sectional view of the top 27 edge of the tub in the direction 7-7 shown in Figure 2;

2g ///

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1 Figure 8 is a perspective view partly cut away 2 to 5how the pliable watertight liner in a preferred 3 embodiment of the present invention; and, 4 Fi~ure 9 is a cross-sectional view in the direc-tion 9~9 shown in Figure 8 and shows the bubbler plenum ~ used in a preferred embodiment of the present invention.

q 11 Turning now to the drawings in which similar 12 parts are denoted by the same reference numeral through-13 out, there is shown in Figure 1 a hot tub construction 14 exemplifying that used in the prior art. Fi~ure 1 has been 15 discussed above, but will be referred to occasionally 16 below.

17 Figure 2 sho~s the hot tub construction in 18 accordance with a preferred embodiment of the present 19 invention installed in a tub 10. ~ypically, the tub 10 20 includes a wall 12 formed of staves which include a cro~e 18 21 by which the staves are interconnected to the flGor 14 of 22 the tub. Typically, the floor 14 is su~orted on a 23 foundation by the chine joists 16.

24 The tub just described and shown in Figure 2 is 25 typical of the type of tub in which the construction of 26 the present lnvention is usually installed. ~owever, it 27 will be clear to those skilled in the art that the con-28 struction of the present invention can also be installed 29 in tubs constructed in other manners, as well as in tanks 30 and pools of various types. The hot tub construction of 31 the present invention could even be installed in a small f~

~g~i3 1 room if desired. Nor is the shape of the tub, tank, pool, 2 or room in which the constxuction is installed a limitation ~ on the usefulness of the concept of the present invention.
4 With some modification of the shape of the elements, the construction of the present invention could be installed 6 in rectangular or hexagonal containers as easily as it can 7 be installed in the circular tub illustrated.
8 In some embodiments of the ~resent invention, it 9 is possible to dispense with the floor 14 of the tub as 10 well as the chine joists16, and in those embodiments, a 11 portion of the struc~ure of the present invention rests on ~2 and ls supported by a foundation separate from the tub, 1~ such as the floor of a patio or of a room. Clearly, care 14 must be taken that the underlying foundation be sufficiently 15 solid and unyielding to support the weight of the hot tub 16 when it is filled with water; a filled tub typically weighs ~7 between 3,000 and 4,000 pounds.
18 For convenience in further describing the present 19 invention, the vertical portion of the tub, tank, pool, pit, 20 or room in which the invention is installed will simply 21 be referred to as the wall of the tub. Likewise, the 22 horizontal surface on which the present invention rests ~3 will be referred to for convenience as the bottom of the 24 tub.
As shown in Figure 2, a bench-like extended seat 24 ~6 is formed by installing within the tub a number of seat 27 segments 30. In the embodiments shown herein, the segments 30 ~7~5i3 1 are identical, but the scope of the invention includes the 2 use of seat segments which are not identical. For example, 3 depending on the shape of the tub or enclosure, there may 4 be two or more sets of seat segments with the identlcal elements of one set being different from the identical 6 elements of another set. The distinctions between the 7 different types of seat segments involve only the size and 8 shape of the seat segments and not the portions of the 9 segments that are deemed -to be inventive. Thus, in some instances the seat segments will be described as similar, ~1 rather than as identical.
12 As illustrated in Figure 2, each of the seat 1~ segments 30 includes a first lateral edge 26 and a second 14 lateral edge 28. Each of the seat segments 30 is a shell-15 like unitary structure that includes a contoured seat 16 portion 32, a back portion 38, a front part 34 of the seat 17 portion 32, and a skirt portion 36.
18 In a preferred embodiment, the seat se~ments 30 19 are attached to the floor 14 by the screws 20 and are also ~ a~tached to the wall 12 by the screws 22. It is recognized 21 that if the seat segment were sufficiently strong and 22 rigid, either the screws 20 or the screws 22 could be 23 omitted.
2~ In a preferred embodiment, the seat segments 30 are molded of ABS, which is acrylonitrile butadiene styrene.
26 In other embodiments, the seat segments may be formed o~
27 a glass impregnated resin.

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_g_ ~9453 1 Flgures 3 and 5 show two embodiments of the seat 2 segments 30 in greater detail.
3 Continuing with Figure 2, in a preferred embodiment, 4 a resilient insulative sheet of closed-cell foamed plastic 80 is applied to a portion of the wall 12 above the seat 6 segment 30 and is applied to cover the portion of the floor 14 7 that is not covered by the seat segments. In other embodiments, 8 the resilient sheet 80 also covers other parts of the seat 9 se~ments 30, such as the seat portion 32, the front part 34 lO and the skirt ~ortion 36. The water in the tub buoys up 11 the bather, and accordingly no great discomfort results if 12 the resilient material 80 does not cover the seat portion 32.
13 In a preferred embodiment, the resilient insulative 14 sheet 80 is not bonded to the portions which it covers; the 15 water pressure is sufficient to hold the material in place.
16 In a preferred embodiment, the resilient insulative sheet 80 17 is a 0.25 inch thick sheet of a closed-cell foamed plastic 1~ sold under the VOLAN trademark.
19 The material 80 serves several important purposes.
20 First, it insulates the water in the hot tub to retard loss 21 of heat. Further, the material 80 provides a resilient 2~ feel to the intexior of the hot tub which enhances the 23 aesthetic appeal of the hot tub. Further, the cushioning 24 effect of the foam material 80 protects users in the 25 event they happen to slip or fall, and it also protects the 26 seat segments 30 a~ainst impacts.
27 In a preferred embodiment, a unitary pliable liner 50 3~ ///

1 covers the footwell, the seats, and the portion of the wall 2 of the tub above the seats. Thus, as shown in Figure 2, 3 the pliable liner 50 includes a floor portion 52, an apron portion 54, a seat portion 56, and back portion 58. As shown in Figure 2, and more clearly in Figure 7, the back portion 58 extends upwardly far enough so that its edge 7 can be reverted over the top of the wall of the tub. This 8 edge is clamped by the hoop 48 in a preferred embodiment.
9 In a preferred embodiment, the pliable liner 50 is formed of 18 mil vinyl and the various portions of it 11 are ultrasonically welded together so that a unitary water-12 tight liner i9 obtained. In another embodiment the liner is 13 vacu-formed or thermo-formed as a shaped one-piece liner.
14 The use of vinyl, or similar plastic for the pliable liner 50 renders it easily cleaned by sponging it with a mild soap in 16 water. Further constructional details of the pliable liner 50 17 are shown in Figures 7-9.
18 With this overview in mind, the many advantages ~9 of the hot tub construction of the present invention as 2~ shown in ~igure 2 can now be appreciated. In contrast with 21 the prior art construction of Figure 1, in the construction 22 of the present invention as shown in Figure 2, the bench-23 like extended seat 24 does not have to be waterproof and 24 therefore can be formed by coupling a number of seat segments 30 without concern that the water will leak through 26 the cracks between the segments. In the construction of 27 the present invention, the pliable liner 50 is the only 28 part that needs to be watertight. In a preferred embodiment, ///

1~7~45~

1 the seat segments 30 nest, as indicated in Figures 4 and 2 6, and individually are much smaller than the rigid one-3 piece liner 2 of Figure 1 used in the prior art. For this 4 reason, the seat segments are much easier to manufacture, to crate, to ship, to handle, to store, and to install. It 6 is particularly noteworthy that the seat se~ments 30 can 7 fit through doors and passageways that would bar the use 8 of the rigid one-piece liner 2 of Figure 1.
9 The tub 10 does not need to be waterproof either, 10 when the construction of the present invention is used, 11 and this is beneficial because the staves of the tub do 12 not have to be accurately milled. Also, as pointed out 13 above, in some embodiments of the present invention, the 14 floor 14 can be dispensed with which reduces the cost of 15 the tub.
16 Also from Figure 2 it can be seen that the seat 17 segments 30 provide a dead air space beneath the seat 18 portion 32 which is highly advantageous because it 19 displaces an amount of water equal to approximately 30%
20 of the capacity of the tub. Thus, less water is required 21 to fill the hot tub, and accordingly there is less water 22 to be heated. This results in faster heating rates, such 23 as 16F per hour instead of 7F per hour. Also, once the 24 water has been heated, the dead air space under the seat 25 portion 32 serves as an excellent insulator helping to 26 retain the heat within the hot tub. The resilient sheet 27 of closed-cell foam 80 further serves to insulate the ~;~7~S~

l water in the hot tub~
2 In summary, the use of a pliable waterproof 3 liner 50 permits the use of a segmented structure for 4 the bench-like extended seat 24 and permits installation in a tub lO which is not necessarily watertight.
Figure 3 is a perspective view of the upper 7 surface of a seat segment 30 used in a preferred embodi-8 ment of the present invention and shown more or less as 9 it appears in Figure 2. Figure 4 is a perspective view ~0 of the underside of the seat segment shown in Figure 3.
ll As shown in Figure 4, in a preferred embodiment, 12 a plastic socket 70 is bonded to the underside of the seat 13 portion 32. The socket 70 receives the end of an upright 14 support member 72 as shown in phantom lines in Figure 3.
15 This further serves to support the seat portion 32. Further sup-~6 pc~rt is provided by the skirt portion 36, which supports the 17 front part 34 of the seat portion 32 and by the attachment 18 of the seat segment 30 to the wall 12 of the tub; the lg holes 46 are provided to facilitate the use of a suitable 20 fastener. Similarly, the holes 44 permit the use of 21 fastener to attach the lowest portion of the seat segment 22 to the floor 1~.
23 Figure 3 is noteworthy for its showing of the 24 structure used for coupling the segments. In the preferred 25 embodiment shown in Figure 3, the first lateral edge 26 26 of the seat segment 30 is provided with a rabbet 40 on which 27 the second lateral edge 28 of a similar seat segment rests ~l~L79~

l when the two segments are juxtaposedO The side panel 42 2 depends from only the rabbeted first lateral edge 26 of 3 the seat segment to facilitate nesting of the segments 4 as suggested by the dashed lines in Figure 4. In a preferred embodiment, the side panel 42 extends to the ~ floor 14 to provide support, but in other embodiments, 7 the side panel 42 does not extend entirely to the floor 14 8 but merely serves as a gusset to-provide greater rigidity 9 to the seat segment.
The preferred embodiment shown in Figures 3 and ll 4 is used in installations providing a 4-foot soaking depth 12 of water, and four identical seat segments 30 like that 13 shown in Fiyure 3 are used to provide a bench-like extended 14 seat around the entire circumference oE the tub.
Figures S and 6 show respectively the upper and 16 under surfaces of an alternative embodiment of the seat 17 segment 30 of the present invention which is intended for 18 use in installations providing a 3-foot soaking depth and 19 in which two identical seat segments are coupled to form 20 the bench-like seat that extends around the entire 21 circumference of the hot tub. This embodiment differs 22 from the embodiment of Figures 3 and 4 in several important 23 ways. The seat segment 30 of Figure S includes a floor 24 portion 74, and three sockets 70 are provided on the 25 underside of the seat portion 32 to receive upright 26 support members similar to that shown in Figure 3.
27 first side panel portion 60 depends from the first lateral 2g ///

.!1! ~7~4S~3 1 edge 26 and a second side panel portion 62 depends from 2 the second lateral edge 28. The first side panel portion 60 3 includes a flange 66 on which the edge 68 of a similar seat segment rests. The flange 66 may be supported by the upright support member 72 shown in Figure 5, although in other embodiments, the first and second side panel 7 portions 60, 62 extend downwardly to the floor 14 of the 8 tub. The holes 64 permit the two halves of the extended 9 bench-like seat to be connected by suitable fasteners.
As indicated by the dashed lines in Figure 6, 1 the seat segments nest for shipping and storage.
12 Because this alternative embodiment of Figures 5 1~ and 6 provides a soaking depth of only 3 feet, it is 14 practical to eliminate the wooden floor 14 of the tub so 15 that the floor portion 74 of the seat segment rests 16 directly on the foundation. With elimination of the floor 17 of the tub, the croze may also be eliminated from the 18 staves.
19 Figure 7 is a cross-sectional view in the plane 7-7 20 of Figure 2 and shows the manner in which the top edge of 21 the pliable liner 50 is reverted over the top of the wall 12 22 of the tub and held in place by the clamping action of the 23 hoop 48. In a preferred embodiment, a border strip 76 is 24 bonded to the upper edge of the pliable liner 50, both 25 to discourage tearing of the edge of the liner and for 26 aesthetic appeal.
2~ Figure 8 is a fractional perspective view of the ~7~453 l pliable liner 50 in a preferred embodiment of the invention.
2 On the back portion 58, just above the seat portion 56 3 a ribbon-like patch 90 is bonded at its edges 96, 98 to 4 create between the patch 90 and the liner 50, a blister-like plenum 94. An air supply fitting 86 admits air to an 6 enlarged foyer plenum 88 which communicates with the 7 blister-like plenum 94. The air flows into the blister-8 like plenum 94 from which the air is discharged through 9 the aperture 92 into the hot tub.
The blister-like plenum 94 of the preferred ll embodiment replaces the pipe-like rigid bubbler ring 8 of 12 Figure 1 used in the prior art, and is a considerable 13 improvement over the rigid bubbler ring because the plenum 94 ~4 of the present invention does not constitute a rigid 15 object lying on the seat of the hot tub.

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16 In other embodiments of the present invention, 17 the plenum 94 is located on the apron portion 54 of the l~ pliable liner, below the front part 34 of the seat.

19 Thus, there has been described a novel and 20 advantageous construction for a hot tub, and it is 21 understood that additional embodiments thereof will be 22 obvious to those skilled in the art. The embodiments 23 described herein together with those additional embodiments 2~ are csnsidered to be within the scope of the invention.

What is claimed is:

Claims (18)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A kit for constructing a spa in a not-necessarily-watertight tub, tank, or pool having a floor and at least one wall, said kit comprising in combination:
more than one seat segments, each seat segment com-prising a rigid unitary shell-like structure including coupling means for interconnecting that seat segment with another seat segment to form a bench-like extended seat within the tub, and further including means for attaching the seat segment to the floor of the tub; and, unitary pliable watertight liner means for covering the portion of the floor not covered by the extended seat.

2. The kit of Claim 1 wherein said unitary pliable watertight liner means further are adapted to cover a portion of the wall of the tub, and further com-prising resilient pliable homogeneous insulative means adapted to be interposed between said unitary pliable watertight liner means and said portion of the wall of the tub.

3. The kit of Claim 2 wherein said resilient pliable homogeneous insulative means is sheet-like.

4. The kit of Claim 2 wherein said resilient pliable homogeneous insulative means further comprise a closed-cell plastic foam.

5. The kit of Claim 1 further comprising resilient pliable homogeneous insulate means adapted to be inter-posed between said unitary pliable watertight liner means and said seat segments.

6. The kit of Claim 1 wherein each of said seat segments further comprises in combination:
a rigid unitary structure having a first lateral edge and a second lateral edge;
a seat portion extending in a generally horizontal disposition from a wall of the tub into the space within the tub; and, first and second coupling means located respectively at said first lateral edge and said second lateral edge of said unitary structure for coupling said first lateral edge to a second lateral edge of a first similar segment and for coupling said second lateral edge to a first lateral edge of a second similar segment.

7. A spa comprising in combination:
a not-necessarily watertight tub having a bottom and at least one wall;
a seat including more than one seat segments coupled together, each seat segment having a back portion disposed against the wall of the tub; and, a unitary pliable watertight liner covering the portion of the bottom of the tub not covered by the seat, and covering the seat.

8. The spa of Claim 7 wherein each of said seat segments comprises a rigid unitary shell-like structure.

9. The spa of Claim 7 wherein each of said seat segments rests on and is supported by the bottom of the tub.

10. The spa of Claim 7 wherein each of said seat segments is adapted to be attached to the bottom of the tub.

11. The spa of Claim 7 wherein each of said seat segments is rests against a wall of the tub.

12. The spa of claim 7 wherein each of said seat segments is adapted to be attached to a wall of the tub.

13. The spa of Claim 7 wherein each of said seat segments further includes coupling means for inter-connecting that seat segment with another seat segment.

14. The spa of Claim 7 wherein said unitary pliable watertight liner means covers a portion of the wall of the tub above said back portion of said seat segments, and further comprising resilient insulative means interposed between said unitary pliable watertight liner means and said portion of the wall of the tub.

15. The spa of Claim 14 wherein said resilient insulative means is sheet-like.

16. The spa of Claim 14 wherein said resilient insulative means further comprise a closed-cell plastic foam.

17. The spa of Claim 7 wherein each of said seat segments further comprises in combination:
a rigid unitary structure having a first lateral edge and a second lateral edge;
a seat portion extending in a generally horizontal disposition from a wall of the tub into the pace within the tub; and, first and second coupling means located respectively at said first lateral edge and said second lateral edge of said rigid unitary structure for coupling said first lateral edge to a second lateral edge of a first similar segment and for coupling said second lateral edge to a first lateral edge of a second similar segment.

18. The spa of Claim 7 further comprising resilient insulative means interposed between said unitary pliable watertight liner means and said more than one seat segments.