GB2271587A - Floor panel unit for sound-proofing double floor assembly - Google Patents

Abstract

The floor panel unit comprises panel members 4 with elongate, wall-shaped supporting legs 3a and 3b of elastomeric material attached to extend along perimetrical edges of lower surfaces. The supporting legs taper in transverse cross-section from upper panel member engaging portions (7) (Fig. 2 not shown) to lower, more flexible, floor surface engaging portions (8) which are formed with readily deformable longitudinally extending projections (9). <IMAGE>

Description

Floor Panel Unit For Sound-proofing Double Floor Assembly The invention relates to a floor panel unit for a sound-proofing double floor assembly in which panel members of such units, such as concrete finishing, are laid on a floor surface. In particular, the invention relates to improved supporting legs attached to the lower faces of the panel members.

In multiple occupancy buildings, such as apartment buildings, the floor underlayer has traditionally been made by constructing joists and sills on a concrete floor surface and laying floor panels thereon.

More recently, however, a prefabricated construction technique has been adopted which utilizes a type of floor panel unit for laying with similar floor panel units on a floor surface to form a sound-proofing double floor, each floor panel unit comprising a panel member and a series of supporting legs of elastomeric material with respective lower, floor surface engaging portions and respective upper, panel member engaging portions attached to a lower face of the panel member adjacent a perimeter thereof.

As shown in Figures 6(a) and (b), the panel members b are of constant size and the supporting legs a are columnar and of a predetermined height with lower, floor surface engaging portions on the floor surface c. This technique compensates for the insufficiency of skilled workers, such as carpenters, and permits under-floor wiring for office machinery, home electric appliances, etcetera.

As the panel members b form a floor underlayer conforming to the surface contour of the concrete floor surface c, which may be uneven, panel members of comparatively small size, about 50 cm square, (and possibly made of particle board,) are used. The supporting legs a are attached by upper, panel member engaging portions to the lower faces of the panel members b at spaced apart locations, for example, one in each of the four corners of the lower faces of each of the panel members b, one in the middle of each of their four perimetrical edges, and one in the center, providing a total of nine supporting legs, between which the under-floor wiring is laid.Furthermore, the supporting legs a are made of molded rubber and taper from their upper, panel member engaging portions to their lower, floor surface engaging portions that they can flex to conform with the undulating contour of the floor surface c, in an attempt to prevent bending of the panel members.

After the floor panel units b are laid on the concrete floor surface c, a carpet d is laid on the upper face of the panel members b as a finishing material. The carpet d is of the unit type, with units of about 50 cm square, laid so that they are offset with respect to the pattern of the panel members b, enabling the double floor to be laid and removed in any desired location, simply by removing the carpet units and the floor panel units underneath them.

In the sound-proofing double floor assembly described above, the flexibility of the finishing layer d (carpet) under a load is closely related to the strength of the panel members b, the number of supporting legs a, and the distances between the legs. If the thickness of the panel members b is increased, their strength is increased, but their weight is also increased, and ease of handling is reduced; their cost is also increased.

On the other hand, if the number of supporting legs on each panel member is increased (4, 5, 9, 16), the flexibility is decreased proportionately, but, even if there are, for example, nine legs, as shown in the Figure, the distance 1 between the supporting legs a at the edges of the floor panel b still amounts to one half of the total length of the edge of the panel, and the relative flexibility of the portions of the panel member between the supporting legs is greater than those portions overlying the panel legs. In consequence, those portions between the supporting legs, will be more depressed by a load applied thereon resulting in an undesirable difference in height between this and an adjacent floor panel unit.

An object of the invention is to provide a floor panel unit for sound-proofing double floors with an improved supporting leg structure which prevents bending at the perimeter of the panel member which is the weak point of the aforementioned floor panels.

According to one aspect of the invention, in a floor panel unit of the type described above, the supporting legs of the series are each wall-shaped, so that the respective panel member engaging portions and the respective floor surface engaging portions extend longitudinally around the perimeter of the panel member.

As the supporting legs extend continuously along the under face of the perimetrical edges of the panel member, (being, in effect, somewhat equivalent to an unlimited number of conventional supporting legs of zero separation), the total support area is increased, and bending at the edges of the floor panel units is markedly reduced or prevented. Thus, the risk of height differences between portions of adjacent panels arising when weight is applied, and risk of breakage from the impact of a dropped load are reduced or eliminated. Furthermore, as the rigidity of the floor panels is increased, relatively light, thin, floor panel units of low-cost can be used, facilitating ease of handling while enabling the total weight of the floor assembly to be kept desirably low.

Preferably, each of the supporting legs tapers in transverse cross-section from the panel engaging portion to the floor surface engaging portion and, desirably, is trapezoidal, so that the floor surface engaging portion is flexible than the panel engaging portion and readily conforms with the contour of an uneven floor surface.

A plurality of small projections are formed on lower faces of the floor surface engaging portions and preferably comprise ridges extending along the lower faces increasing the conformance.

Supporting legs having the described cross-section can be produced by extrusion, affording an increased production rate and economy of manufacture by comparison with the conventional columnar molded rubber supporting legs which were produced by batch molding and vulcanization.

In one construction, selected of the supporting legs are formed with cut-outs extending transversely therethrough for receiving wires laid under the panel members.

As a result, the wiring, pipes, conduits of office machinery can be accommodated under the floor panel units.

Desirably, a further series of wall-shaped, supporting legs of elastomeric material with respective lower, floor surface engaging portions and respective upper, panel member engaging portions are attached by their respective panel member engaging portions to locations of the lower face of the panel member within the supporting legs of first mentioned series so that the supporting legs of the further series cooperate with the supporting legs of first mentioned series to define between them areas of the lower face of the panel member which are approximately equal to each other.

By making the areas delineated by the first and second supporting legs approximately equal, the stresses from applied loads are more evenly distributed over the area of the floor panel unit reducing local bending and improving impact resistance which results in an increase in overall strength.

In one construction, the panel member has two, adjacent perimetrical edges and a layer of finishing material having perimetrical dimensions which are substantially equal to perimetrical dimensions of the panel member is attached to an upper face of the panel member with two, adjacent perimetrical edges of the layer of finishing material extending parallel to and in spaced apart relation from said two, adjacent perimetrical edges of the panel member.

As the layer of finishing material is attached to the upper faces of the floor panels in an offset fashion, numerous floor panel units can be laid so that they adhere tightly to each other and a double floor assembly can be formed in which the patterns of the panel members and the surface material can be offset from each other by only a single laying operation so that the number of assembly steps at the site is decreased, resulting in energy saving and lower applied cost.

Advantageously, the panel member is square and the supporting legs of said series are attached at predetermined spacings apart from perimetrical edges of the panel member to form a quadrilateral; a further series of wall-shaped, supporting legs of elastomeric material with respective lower, floor surface engaging portions and respective upper, panel member engaging portions are attached by their respective panel member engaging portions to locations of the lower face of the panel member within the first mentioned series, to form a further quadrilateral of reduced size, and an additional wall-shaped, supporting leg of elastomeric material with a lower, floor surface engaging portion and an upper, panel member engaging portion is attached by the panel member engaging portion to a central location of the lower face of the panel member within the further series.

As multiple rows of wall-shaped supporting legs are placed on the lower face of the panel member, the impact strength of the floor panel unit is increased, and the strength distribution is improved.

In a more particular embodiment adjacent longitudinal ends of at least some of adjacent supporting legs of the first series are spaced apart from each other to provide wire receiving gaps therebetween.

The layer of finishing material may be carpet tile with a carpet weave direction matched to the longitudinal direction of the additional supporting leg. This enables the weave direction of the carpet tile to be discerned from even the lower faces of the floor panel units, and the carpet tiles can be easily laid in a desirable checkerboard pattern.

According to another aspect of the invention, a doublefloor assembly comprises comprises a plurality of floor panel units each comprising a quadrilateral panel member and a series of wall-shaped supporting legs of elastomeric material attached to a lower face thereof to extend longitudinally of and at predetermined spacings apart from perimetrical edges of the panel member, the floor panel units being laid on the floor surface with the panel members in edge-to-edge relation so that lattice-like spaces are formed under the panel members between adjacent supporting legs of adjacent floor panel units providing raceways for receiving under-floor wiring.

This provides wiring receiving spaces or raceways under the floor between supporting legs of adjacent floor panel units which are twice as large as the separation of the supporting legs from the adjacent edges of the panel members from which they depend enabling a greater bulk of underfloor wiring to be installed.

Advantageously, adjacent longitudinal ends of at least some of adjacent supporting legs of the first series are spaced apart from each other to provide wire receiving gaps therebetween. Preferably, at least one corner of each panel member is cut away or bevelled providing a lead out aperture through which under-floor wiring can be pulled above the floor. This is an efficient method of providing lead out apertures for the under-floor wiring, as by a single cut.

In a particular construction, each of the panel members is square and the- supporting legs of said series are attached to the lower face in a quadrilateral arrangement and at predetermined spacings apart from the perimetrical edges; a further series of wall-shaped, supporting legs of elastomeric material are attached depend from locations of the lower face of the panel member within the first mentioned series to form a further quadrilateral arrangement of reduced size and an additional wall-shaped, supporting leg of elastomeric material is attached to depend from a central location of the lower face of the panel member within the further series so that the raceways formed by the first series can accommodate main wiring lines and raceways for wiring lines branching from said main wiring lines are formed between adjacent supporting legs of the first mentioned and further series.

This enables splicing and branching operations to be performed by pulling the wires through the spaces between the first and further series of supporting legs as well as any junction boxes or connectors there for to be accommodated therein, thereby avoiding obstruction of the main or trunk wiring routes extending along the lattice or grid and enabling a continuous wiring operation to be performed easily.

According to a further aspect of the invention, a leg member for supporting a floor panel member of a soundproofing double floor comprises an elongate, wall-shaped strip of elastomeric material formed by extrusion and having an elongate, upper, panel member engaging portion and a lower, floor surface engaging portion and tapering in width from the upper to the lower portion so that the lower portion is flexible relative to the upper portion and is sufficiently flexible to conform with a contour of an uneven floor surface when supporting a floor panel.

This approach affords extremely economic mass production at high volume.

According to a further aspect of the invention, there is provided a floor panel unit for laying together, in edgeto-edge relation, with similar floor panel units, on a floor surface to form a double floor and comprising a panel member and strip-like supporting leg means with an upper, panel member engaging portion extending around a perimeter of a lower face of the panel members and lower, floor surface engaging portion which is sufficiently resiliently flexible to conform with a contour of an uneven floor surface when supporting a panel member.

Embodiments of floor panel units and sound-proofing double floor assemblies, panel units and supporting legs thereof will now be described by way of example only and with reference to the accompanying drawings in which: Figure 1(a) is a lateral cross-sectional fragmentary view of a sound-proofing double floor assembly according to the invention; Figure l(b) is a schematic underplan view of the lower face of the sound-proofing double floor assembly of Figure 1(a); Figure 2 is a perspective view, partly in transverse cross-section, of a supporting leg according to the invention; Figure 3 is an underplan view of a floor panel unit according to the invention showing the locations at which a first and a second series of supporting legs are attached to the lower face of the panel member;; Figure 4 is an underplan view of another embodiment of floor panel unit according to the invention showing the locations at which a first and a second series of supporting legs are attached to the lower face of the panel member; Figure 5 is an underplan view of a further embodiment of floor panel unit according to the invention showing the locations at which a first and a second series of supporting legs are attached to the lower face of the panel member; Figure 6(a) is a lateral cross-sectional fragmentary view of a sound-proofing double floor assembly according to the prior art; Figure 6(b) is a schematic underplan view of the lower face of the sound-proofing double floor assembly of Figure 1(a); Figure 7(a) is a lateral cross-sectional fragmentary view of yet another embodiment of individual floor panel unit according to the invention; ; Figure 7(b) is a schematic underplan view of the lower face of the floor panel unit of Figure 7(a); and, Figure 8 is a schematic underplan view of the lower face of a portion of a sound-proofing double floor assembly laid using floor panel units of Figure 7(a) and Figure 7(b).

As shown particularly in figures 1(a) and l(b), the sound-proofing double floor 1 comprises floor panel units 4 with wall-shaped, rubber supporting legs 3 attached to their lower faces and laid in edge-to-edge relation on a concretefinished floor surface 2, and a carpet layer 5 is laid on top of this as a finishing material.

The floor panels 4 are made by cutting particle board, or similar suitable material, into 50 cm squares and attaching the supporting legs 3 to their lower faces using adhesives or double-sided tape. Supporting legs 3a of a first series of supporting legs, eight in number, are attached to the respective lower faces of each of the floor panels 4 to extend along their peripheries adjacent and spaced apart a predetermined distance from their perimetrical edges, and legs 3b of a second series, four in number are attached extending at an angles of 45 degrees at locations of the lower faces within the supporting legs 3a of the first series, so that they delineate, with the supporting legs 3a of the first series, right-angled triangles, approximately equal in area to each other.

The supporting legs 3a of the first series are of identical shape to those of the second series so that they are interchangeable, thereby reducing cost. However, the most desirable construction is one in which the length of the supporting legs 3b of the second series are somewhat shorter than the supporting legs 3a of the first series and, as shown in Fig. 5, the areas of the triangles at the four corners and the central square, delineated or marked off by the supporting legs 3a and 3b, are precisely equal.

Gaps or cut-outs 6 between the supporting legs 3a form a horizontal grid or lattice-shape raceway d, indicated by the dotted lines in Fig. 1 (b), in which wiring, pipes, conduits etc., of office automation machines can be installed. Alternatively, supporting legs for the first series can be increased in length to double the length of those described above and the wire receiving cut-outs formed by severing transversely through the middle of the longer legs.

As shown in Figure 2, the supporting legs 3a and 3b of both series, are each a strip of generally trapezoidal transverse cross-section, tapering from a wide, elongate, upper panel member engaging portion 7 to a narrow, elongate, lower floor surface engaging portion 8 on a lower face of which a three small projections 9 are formed as longitudinally extending ridges.

The supporting legs are manufactured in strip form of generally trapezoidal transverse cross-section by longitudinal extrusion molding as a generally square material after which they are vulcanized and cut to a specified length. In contrast, the conventional columnar supporting legs a, shown in Fig. 6, must be batch-vulcanized and injection molded which is a markedly less productive manufacturing technique.As the supporting legs 3a of the first series extend continuously along the under face of the perimetrical edges of the panel member 4, and each form a continuous, linear load bearing surface, (being, in effect, somewhat equivalent to an unlimited number of conventional supporting legs of zero separation), in contrast to the pointed supports of the conventional legs, the total support area provided by the supporting legs is increased, and risk of bending at the edges of the floor panel units when weight is applied on such edges is markedly reduced or obviated.

Thus, the risk of height differences and wobbling of adjacent panels arising when weight is applied to edges of only one of the panels as well as risk of breakage from the impact of a heavy object falling thereon (or on the carpet overlay) are reduced or eliminated.

Furthermore, as the rigidity of the floor panel units is increased, relatively light, thin, floor panel units of low-cost can be used, facilitating handling while enabling the total weight of the floor assembly to be kept desirably low. Furthermore, as a result of the trapezoidal cross section of the supporting legs with wide upper parts 7 and the narrow lower parts 8, and the series of small projections 9 on the lower surfaces 8, when the floor panels 4 are laid on the concrete-finished floor surface 2, the narrowed lower ends of the supporting legs 3 and the small projections 9 on the lower surfaces 8 are suitably deformed and readily conform to unevenness in the floor surface.

In addition, the wiring, pipes, conduits etc. of office machinery accommodated under the floor by laying through the gaps 6 between the supporting legs can be changed simply by removing individual floor panel units above the wiring.

By making the triangular areas enclosed by the supporting legs of the first and second series approximately equal, the balance between the bending and impact strength characteristics of each floor panel when loads are applied to the finishing material 5 (carpet) are improved, and the overall strength is increased.

approximately equal, the bending of the floor panels and the balance of their impact strengths are improved, and the strength is increased.

Figures 3, 4, and 5 show different arrangements of first and a second series of supporting legs 3a and 3b on the lower face of the panel members 4.

Figure 3 shows an embodiment in which the supporting legs 3a of the first series are attached extending longitudinally of edges adjacent the four corners of the floor panels 4, as described above, and in which the supporting legs 3b of the second series are attached at locations inside the first series for reinforcement; Figure 4 shows an embodiment in which the supporting legs 3a of the first series are similarly located to those of the embodiment of Figure 3 and the supporting legs 3b of the second series are located inside them arranged in an Xshape. The supporting legs of the embodiments of Figures 3(a) and 3(b) all have the same length L1.

Figure 5 shows an embodiment in which the supporting legs 3a (lengths L1) of the first series are similarly located to those of the embodiment of Figure 3 and the supporting legs of the second series 3b are of length L2, less than L1, and are located re attached inside them so that the areas of each of the four generally pentangular spaces defined or marked off by the supporting legs 3a and 3b of the first and second series and the central generally octangular area defined or marked off by the supporting legs 3b of the second series are approximately equal.In this case, with the centers of the panels members 4 represented by x, the center points between the centers x and the corners are represented by y, and the center points between the centers x and the center points of the outer edges represented by z, the bending or deflection (in mm) produced at the points x, y, and z when loads were applied was as shown below. The panel members were made of particle board 15 mm thick and 500 mm square, and 200 kg loads, on a circle of 25mm diameter, were applied to the points x, y, and z.

Point x Point y Point z Arrangement of Fig. 3 3.63 2.45 2.86 Arrangement of Fig. 4 3.19 2.54 3.05 Arrangement of Fig. 5 2.61 2.35 2.43 (Unit: mm) These measurements show that the arrangement of Fig. 5 results in the smallest amount of deflection at points x, y, and z. Furthermore, this arrangement requires the smallest quantity of supporting legs material and is, therefore, the most economical.

In another embodiment of floor panel unit 10, shown in Figures 7(a) and (b), the supporting legs 13 of a first series are attached to the lower face of the panel members 12, (each of particle board: 498 mm square), in a square pattern or arrangement at a specific separation (25 mm) from the edge. In each panel member, the supporting legs 14 of a second series are located inside the supporting legs 13 of the first series, in the same, pattern, reduced in size, and supporting legs 15 of a third series are attached inside those of the second series, one leg for each panel member. The supporting legs 13, 14, and 15 are arranged in multiple rows parallel to the edges of the panel members 12.

When a double floor 11 is made by laying the floor panel units 10 as shown in Figure 8, an under-floor space (50 mm) which is twice the said specific separation (25 mm) is formed between the adjacent supporting legs of the first series 13 under the floor can be used as the underfloor wiring route or raceway 16. Thus a 50 mm wiring route or raceway 16 is formed under the floor in a lattice shape at 500 mm intervals. The quantity of under-floor wiring can, therefore, be greater than with the type shown in Figure 1. Furthermore, after removing only a single one floor panel unit 10 from the double floor 11, inspection and work on the four wiring routes 16 around it can be performed resulting in an improvement of access and wiring workability relative to the embodiment of Figure 1.

In addition, the arrangement of the legs 13, 14, and 15 obviates any requirement for cutting in the central parts of the edges, which are mechanically important, the resistances to bending and impact are excellent when compared with the arrangement of the embodiment of Figure 1. As the supporting legs 14 of the second series are located inside the supporting legs 13 of the first series and in a similar pattern and, furthermore, as the third rubber supporting legs 15 are attached inside the second series, applied stress is more evenly distributed throughout the floor panel unit.

Furthermore, since the number of attachments of the rubber supporting legs 13, 14, and 15 to the floor panel 12 is reduced from 12 to 9, compared to the type of Figure 1, an advantageous manufacturing operation is obtained.

The supporting member placement pattern and the placement positions are determined by experiment, so that bending or deflection which occurs when a load is applied to the floor panel unit 10 is relatively evenly distributed, reducing the risk of cracking under impact.

As wire receiving gaps 17 are formed in the four corners of the floor panel unit between adjacent ends of the supporting legs 13 there is no effect on the mechanical strength. Wires can be pulled from the aforementioned wiring route 16 through the gaps 17 to an inner location for connection to the branching junction box 18 which is placed in the space between supporting legs 13 and 14 of the first and second series which form a raceway.

If it were not possible to lead wires to be spliced through gap 17 out of the route 16 and to accommodate junction box 18 there may not be sufficient clearance from other obstructing wire within route 16 for the splicing operation to be performed efficiently or at all.

One of the corners of the panel member 12 is bevelled or cross cut along a severance line of approximately 15 mm, forming a triangular wiring rising hole 22, through which under-floor wiring can be brought above the floor.

This is advantageous compared with the embodiment of Figure 1, where the center part of the outer edge of the panel member 4 must be cut out and a wiring rising hole (not shown) formed, as this example, one need only cut one of the corners of the flooring panel 12. The working cost is reduced, which is economically advantageous.

Furthermore, cutting out the center part of the edge of the floor panel 4, as would be required in the embodiment of Figure 1, would have the most the most severe effect on the mechanical strength (as shown in the above table).

Therefore, one cannot cut a large hole. This is not a problem when bringing up a small quantity of narrowdiameter wiring, as used in residences, but it is not suitable or practicable for the large quantity of largediameter wiring, used in offices and which also needs to be changed frequently. When the under-floor wiring is pulled up above the floor from the aforementioned wiring rising hole 22, cross-shaped cuts, through which the wiring is passed, are made in the carpet tile 23 on top of the wiring rising hole 22.

In addition, although in the example shown in the Figure, a portion is cut out of only one corner of the floor panel 12, all corners my be similarly cut. In this case, the wiring rising holes 22 have a square form when the corners are fitted together when four floor panel units 10 are laid edge-to-edge.

A layer of surface finishing material (carpet tiles, 500 mm square) which is a little larger than the panel member 12 ,(498 mm square), is attached to the upper face of thereof so that the layer is offset 30 mm with respect to, and lies parallel to, the edges of the adjacent floor panels 12. When these floor panel units 10 are laid with the carpet tiles 23 tightly adhered thereto, slight gaps are automatically formed between adjacent panels members 12 which prevents the panel members 12 rubbing against each other and the floor squeaking while the feeling of walking on them is improved.

When the carpet tiles 23 are attached to the upper faces of the floor panel units 10, the direction of weave of the carpet tiles 23 is matched to the longitudinal direction of the supporting legs 15 of the third series so that the direction of weave of the carpet tile 23 is indicated on the back of the floor panel units and can be discerned from the lower face of the floor panel unit 10, even if the carpet tile 23 itself cannot be seen and the carpet tiles 23 can be easily laid in a checkerboard pattern. Furthermore, when cut-outs 21 are made in one corner of each of the floor panels 12, as in the example shown in the diagram, the direction of the panels 12 is determined, so that, in order to lay the carpet tiles 23 in a checkerboard pattern, the same number of floor panel units 10 are made and laid, so that the cut-outs 21 of adjacent floor panel units subtend an angle of 90 degrees with the supporting legs of the third series.

Claims (27)

Claims

1. A floor panel unit of a type for laying with similar floor panel units on a floor surface to form a sound-proofing double floor and comprising a panel member and a series of supporting legs of elastomeric material with respective lower, floor surface engaging portions, and respective upper, panel member engaging portions attached to a lower face of the panel member adjacent a perimeter thereof, wherein, the supporting legs of the series are each wall-shaped, so that the respective panel member engaging portions and the respective floor surface engaging portions extend longitudinally around the perimeter of the panel member.

2. A floor panel unit according to claim 1, wherein each of the supporting legs tapers in transverse crosssection from the panel engaging portion to the floor surface engaging portion so that the floor surface engaging portions are more flexible than the panel engaging portions and readily conform with the contour of an uneven floor surface.

3. A floor panel unit according to claim 2, wherein said supporting legs are trapezoidal in transverse crosssection.

4. A floor panel unit according to any one of the preceding claims, wherein a plurality of small projections are formed on lower faces of the floor surface engaging portions.

5. A floor panel unit according to claim 4, wherein said plurality of small projections comprise ridges extending along the lower faces.

6. A floor panel unit according to any one of the preceding claims, wherein selected of the supporting legs are formed with cut-outs extending transversely therethrough for receiving wires laid under the panel members.

7. A floor panel unit according to any one of the preceding claims, wherein the panel members are square and the supporting legs extend for a majority of the lengths of respective edges of the panel members.

8. A floor panel unit according to any one of the preceding claims, wherein a further series of wall-shaped, supporting legs of elastomeric material with respective lower, floor surface engaging portions and respective upper, panel member engaging portions are attached by their respective panel member engaging portions to locations of the lower face of the panel member within the supporting legs of first mentioned series so that the supporting legs of the further series cooperate with the supporting legs of first mentioned series to define between them areas of the lower face of the panel member which are approximately equal to each other.

9. A floor panel unit according to any one of the preceding claims, wherein the panel member has two, adjacent perimetrical edges and a layer of finishing material having perimetrical dimensions which are substantially equal to perimetrical dimensions of the panel member is attached to an upper face of the panel member with two, adjacent perimetrical edges of the layer of finishing material extending parallel to and in spaced apart relation from said two, adjacent perimetrical edges of the panel member.

10. A floor panel unit according to any one of claims 1-6, or 9 wherein the panel member is square and the supporting legs of said series are attached at predetermined spacings apart from perimetrical edges of the panel member to form a quadrilateral; a further series of wall-shaped, supporting legs of elastomeric material with respective lower, floor surface engaging portions and respective upper, panel member engaging portions are attached by their respective panel member engaging portions to locations of the lower face of the panel member within the first mentioned series, to form a further quadrilateral of reduced size, and an additional wall-shaped, supporting leg of elastomeric material with a lower, floor surface engaging portion and an upper, panel member engaging portion is attached by the panel member engaging portion to a central location of the lower face of the panel member within the further series.

11. A floor panel unit according to claim 9, wherein the layer of finishing material is carpet tile with a carpet weave direction matched to the longitudinal direction of the additional supporting leg.

12. A floor panel unit according to any one of the preceding claims wherein, adjacent longitudinal ends of at least some of adjacent supporting legs of the first series are spaced apart from each other to provide wire receiving gaps therebetween.

13. A double-floor assembly comprising a plurality of floor panel units each comprising a quadrilateral panel member and a series of wall-shaped supporting legs of elastomeric material attached to a lower face thereof to extend longitudinally of and at predetermined spacings apart from perimetrical edges of the panel member, the floor panel units being laid on the floor surface with the panel members in edge-to-edge relation so that lattice like spaces are formed under the panel members between adjacent supporting legs of adjacent floor panel units providing raceways for receiving under-floor wiring.

14. A double-floor assembly according to claim 13 wherein at least one corner of each panel member is bevelled providing a lead out aperture through which under-floor wiring can be drawn above the floor.

15. A double-floor assembly according to any one of claims 13 and 14 wherein, adjacent longitudinal ends of at least some of adjacent supporting legs of the first series are spaced apart from each other to provide wire receiving gaps therebetween.

16. A double-floor assembly according to claim 15 wherein each of the panel members is square and the supporting legs of said series are attached to the lower face in a quadrilateral arrangement and at predetermined spacings apart from the perimetrical edges; a further series of wall-shaped, supporting legs of elastomeric material are attached to depend from locations of the lower face of the panel member within the first mentioned series to form a further quadrilateral arrangement of reduced size and an additional wall-shaped, supporting leg of elastomeric material is attached to depend from a central location of the lower face of the panel member within the further series so that the raceways formed by the first series can accommodate main wiring lines and raceways for wiring lines branching from said main wiring lines are formed between adjacent supporting legs of the first mentioned and further series.

16. A leg member for supporting a floor panel member of a sound-proofing double floor comprising an elongate, wall-shaped strip of elastomeric material formed by extrusion and having an elongate, upper, panel member engaging portion and a lower, floor surface engaging portion and tapering in width from the upper to the lower portion so that the lower portion is flexible relative to the upper portion and is sufficiently flexible to conform with a contour of an uneven floor surface when supporting a floor panel member.

17. A leg member according to claim 16 wherein the floor surface engaging portion is formed with a plurality of longitudinally extending ridges.

18. A floor panel unit according to claim 10, wherein supporting legs of the first mentioned series are parallel to supporting legs of the second series.

19. A floor panel unit for laying together, in edgeto-edge relation, with similar floor panel units, on a floor surface to form a double floor and comprising a panel member and strip-like supporting leg means with an upper, panel member engaging portion extending around a perimeter of a lower face of the panel members and lower, floor surface engaging portion which is sufficiently resiliently flexible to conform with a contour of an uneven floor surface when supporting a panel member.

20. floor panel unit substantially as hereinbefore described with reference to and as shown in Figures 1(a) and (b) of the accompanying drawings.

21. A floor panel unit substantially as hereinbefore described with reference to and as shown in Figure 3 of the accompanying drawings.

22. A floor panel unit substantially as hereinbefore described with reference to and as shown in Figure 4 of the accompanying drawings.

23. A floor panel unit substantially as hereinbefore described with reference to and as shown in Figure 5 of the accompanying drawings.

24. A floor panel unit substantially as hereinbefore described with reference to and as shown in Figures 7(a) and (b) and 8 of the accompanying drawings.

25. A double-floor assembly substantially as hereinbefore described with reference to and as shown in Figure l(b) of the accompanying drawings.

26. A double-floor assembly substantially as hereinbefore described with reference to and as shown in Figure 8 of the accompanying drawings.

27. A leg member for supporting a floor panel member of a sound-proofing double floor substantially as hereinbefore described with reference to and as shown in Figure 2 of the accompanying drawings.