IMPROVEMENTS IN AND RELATING TO RAISED FLOORING SYSTEMS

Abstract: The present invention provides a pedestal (10) for a raised flooring system, which pedestal (10) comprises a base means (20) and a head-cap (40) supported by the said base means (20); which head-cap (40) is adapted to carry one or more flooring panels (50); wherein the said base means (20) includes a stack of one or more incremental portions (22), the number of incremental portions (22) being determined by the required spacing of the one or more panels (50) from a sub-floor on which the base means (20) stands. The present invention also comprehends a flooring system comprising a plurality of pedestals (10) according to the invention and a plurality of flooring panels (50) adapted to be supported on the said pedestals (10).

Description: IMPROVEMENTS IN AND RELATING TO RAISED FLOORING SYSTEMS DESCRIPTION The present invention relates to improvements in and relating to raised flooring systems, and has particular reference to a pedestal for a raised flooring system. A raised flooring system which is available to the public at the time of writing comprises a plurality of rectilinear timber flooring panels and a plurality of height-adjustable pedestals arranged to support the said flooring panels above a sub-floor. Each pedestal has a base which comprises an upstanding, cylindrical metal post having a threaded, axial bore formed therein. The bore carries an upstanding threaded cylindrical adjustor member having a disc-shaped head-cap at its upper end. The height of the head-cap above the sub-floor can be adjusted by screwing the adjustor member in to or out from the upstanding post, thereby to adjust the overall height of the pedestal. The head-cap has a generally planar upper surface which is provided with four upstanding radially-directed walls which divide the surface into four quadrants. The walls serve to locate the corners of four of the flooring panels when the pedestals are arranged on the sub-floor, such that each corner of each flooring panel is partially supported by a pedestal. This prior art flooring system can be used to provide a floor which is raised above a sub-floor, wherein the total floor depth is in the range of about 70mm to about 500mm or more. Further, the provision of height-adjusting means in each pedestal allows a level floor to be supported above an uneven sub-floor. A major problem with the above described flooring system, however, is that the spacing between the floor and the highest point of the sub-floor must be at least 40mm; the depth of a typical flooring panel is about 30mm. Thus, where headroom is restricted, the flooring system can not be employed if the highest point of the sub-floor allows a total depth of sub-floor space plus flooring panel of less than about 70mm. There is, therefore, a need for a raised flooring system that can be used where the desired sub-floor spacing over at least some of the area is less about 40mm. Furthermore, since cast-metal pedestals are relatively expensive to produce for shallow sub-floor spacings between the floor and sub-floor, a less expensive system is required. According to one aspect of the present invention, therefore, there is provided a pedestal for a raised flooring system; which pedestal comprises base means and a head cap supported by said base means, which head cap is adapted to carry one or more flooring panels; wherein said base means includes a stack of one or more incremental portions, the number of incremental portions being determined by the required spacing of the one or more panels from a sub-floor on which the base means stands. A plurality of pedestals in accordance with the present invention may be arranged on a sub-floor to provide a supporting structure for a plurality of floor panels which form a floor. According to another aspect of the present invention, therefore, there is provided a flooring system which comprises a plurality of pedestals and a plurality of flooring panels; each pedestal having base means and a head cap supported by said base means, which head cap is adapted to carry one or more of the flooring panels, and wherein the said base means includes a stack of one or more incremental portions, the number of incremental portions being determined by the required spacing of the one or more panels from a sub-floor on which the base means stands. The pedestals may be arranged in a regular array on the sub-floor, each pedestal being arranged to support one or more flooring panels. Each flooring panel may be supported on one or more pedestals, each pedestal being provided to support or partially support one flooring panel. Alternatively, the pedestals may be arranged to support the panels at their sides or corners such that two or more panels are partially supported on one pedestal. In one aspect of the invention, each pedestal may be arranged partially to support four generally rectangular flooring panels, the flooring panels being placed over the array of pedestals such that each pedestal supports a corner of four neighbouring panels. The pedestal of the present invention may further include clamp means to provide a positive engagement of the floor panel(s) to the base means. The clamp means may comprise a ferrule and a retaining plate. The ferrule may be fastened to and extend upwardly from the base of the pedestal and may have a threaded central bore formed therein. With the flooring ρanel(s) in the fitted position, the retaining plate may be placed over the panel(s) supported on the pedestal and may be held in place by a bolt which extends downwardly into the threaded bore of the ferrule. The incremental portions may be formed from chipboard or any other suitable wood based product known to a man skilled in the art. Each incremental portion may have the same depth as each of the other portions or may be different. In some embodiments, said incremental portions may be made from a high quality load bearing chipboard. The stack may be generally rectilinear; and the said incremental portions may be generally rectangular, typically square, in cross-section. Thus the stack may have four substantially planar side faces; each side face being arranged substantially orthogonally to its adjacent side faces. Said incremental portions may be laminated together to form a consolidated base by interposing a layer of adhesive between each incremental portion and its neighbour. Alternatively, the incremental portions may be secured together by means of mechanical fixings such as screws, nails or the like. The adhesive used in lamination may be a PVA non-contact adhesive. The stack may be coated or covered with a fire resisting or fire retarding material. In one aspect of the invention, the side faces of the stack may be covered with an aluminium foil. The foil may be attached to the said side faces by a high-temperature adhesive. The aluminium foil may have an adhesive backing. In one embodiment, the stack is covered with an aluminium foil tape such as that which is commercially available under the reference AS252 from Adhesive Specialists Ltd of London, United Kingdom, having a thickness of 40μ and a pressure sensitive acrylic adhesive backing. The head cap may be configured to be seated on an upper surface of the top-most incremental portion of the stack and may be provided with a generally planar upper surface for supporting the floor panels. The head cap may be provided with one or more upstanding walls or nibs for locating one or more edges of the supported floor panels. The base means may further include a number of packing pieces or shims which can be disposed between the top most incremental portion and the head cap in order to adjust the total height of the head cap above the sub- floor. Such shims can be used to compensate for an uneven sub-floor and to provide a level floor. The shims may be made from thin rectangular wafers of wood based board or any other suitable material. Where the pedestal is provided with means for clamping the floor pedestal to the base means, the clamp means may also serve to effect squeezing of the shims between the stack of incremental portions and the head-cap thereby to provide a rigid and consolidated pedestal structure. The head-cap may be provided with one or more depending walls. Each wall may be arranged to lie closely juxtaposed or contiguous one of said side faces of the stack. In a particular embodiment, the head-cap may have a generally square upper wall and four depending walls, which latter serve to define a peripheral depending skirt forming a sleeve around an upper portion of the base. The said depending walls may be arranged to restrain the head-cap from rotation with respect to the said base. The ferrule may be adapted to extend upwardly through a hole provided in a flooring panel; alternatively, where the pedestal is configured to support the corners of more than one flooring panel, the ferrule may be adapted to extend upwardly through a gap between adjacent edges/corners of the neighbouring panels. The ferrule may be integral with the head cap. Alternatively, the ferrule may be provided with a generally cylindrical, brass, hollow body portion which is accommodated in a central vertical hole of generally circular cross-section formed in the stack of incremental portions; the ferrule may extend upwardly through a hole formed in the said head cap. The ferrule may be provided towards its lower end with an annular outwardly directed flange which is received in an annular rabbet provided in the hole in the stack. The engagement of the annular flange in the rabbet may serve to restrain the ferrule from being drawn upwardly through the hole as the retaining plate is bolted down onto the upper surface of the floor. In a preferred embodiment of the present invention the ferrule may be splined in the stack of incremental portions to restrain the ferrule from rotation with respect to the base. The ferrule may extend only through the uppermost incremental portion of the base and the rabbet may be formed in the lower surface of the uppermost incremental portion; the ferrule may be splined in the upper incremental portion before the portions forming the stack are laminated together. The retaining plate may be adapted to abut the upper surface of each of the flooring panels. The upper surfaces of the neighbouring flooring panels may define a recess adapted to receive the retaining plate flush with the upper surface of the floor. The recess may be circular in cross-section and the retaining plate may be an annulus having a central hole adapted to receive the bolt. The retaining plate may be provided with a plurality of depending, circumferentially spaced teeth. Such teeth may be arranged to pierce into the floor panels supported by the pedestal. Where the pedestal is arranged to support a number of adjacent panels, such toothed retaining plate may be adapted to engage each panel thereby to restrain said panels from relative lateral movement. Following is a description by way of example only and with reference to the accompanying drawings of methods of carrying the present invention into effect. In the drawings:- Figure 1 is a perspective view showing the general layout of the pedestal of the present invention. Figure 2 is a cross-section through the pedestal of Figure 1. A floor comprising a plurality of planar, square or rectangular flooring panels 50 is supported above a sub-floor 14 by a plurality of pedestals 10 which are arranged in a regular array. Each pedestal 10 is fixedly attached to the sub-floor and is arranged to support partially each of four neighbouring panels 50 at their adjacent corners. The raising of the floor on the pedestals creates a sub-floor space between the sub-floor and the floor which can be used to accommodate electrical cables, gas pipes, water mains and/or other conduits; the sub-floor space can also be used for storage. Each pedestal 10 includes an upstanding base 20 which is formed from a stack of incremental base portions 22. Each incremental portion 22 is generally square in cross-section and has a depth of about 18mm. The incremental portions 22 forming the base 20 are laminated together by a layer of PVA non-contact adhesive interposed between each incremental portion 22 and its neighbours. The bottom incremental portion 23 of the stack is fixedly attached to the sub-floor 14 by a layer of an adhesive 21 such as an epoxy resin. The top incremental portion 24 of the stack has a square, planar upper surface 25 and is provided with a vertical, central hole 26 of circular cross-section which extends through upper portion 24. Hole 26 accommodates an upstanding cylindrical brass ferrule 30 which protrudes upwardly of upper surface 25 and is provided towards its lower end with a peripheral flange 31 which engages in a cooperating rabbet 27 formed in the lower end of hole 26. Ferrule 30 is provided with an internal threaded bore 32. Base 20 carries at its upper end a head cap 40 which is formed from a plastics material. Head cap 40 has a generally square crown 41 having dimensions slightly larger than the dimensions of base 20 and a thickness of about 2mm; head cap 40 has an integral, peripheral depending skirt 42 formed from four rectangular down-turned fins 43. Crown 41 has a planar upper surface 46 and has a circular central hole 44. Head cap 40 is provided with four rectangular upstanding floor panel locating pieces 45 which are arranged radially outwardly from central hole 44, each piece 45 being disposed orthogonally to a side of square crown 41; the locating pieces 45 divide upper surface 46 into quarters. Head cap 40 is pushed onto base 20 such that the protruding portion of ferrule 30 extends upwardly through hole 44 and such each fin 43 lies in close juxtaposition to a side, and towards the top, of the stack of incremental portions 22. The total height of each pedestal can be adjusted slightly by interposing one or more packing pieces or shims 60 between the underside of crown 41 and the upper surface 25 of top incremental portion 24. Each shim 60 is provided with a central hole to permit the shim 60 to be placed over ferrule 30. Thus, where the sub-floor is uneven, the pedestals can be adjusted to provide a level support for flooring panels 50. Once each base 20 has been fitted with a head cap 40, the flooring panels 50 can be laid on the array of pedestals to form the floor. The upper surface of each flooring panel 50 is cut away at each corner such that the cut away portions 52 of four neighbouring flooring panels 50 form a generally circular recess arranged concentrically with hole 44 and ferrule 30. The threaded bore 32 of ferrule 30 receives a bolt 80 which locates at its upper end an annular fixing disc 70 having a central hole 71. Disc 70 is arranged to be accommodated in the circular recess flush with flooring panels 50. Bolt 80 passes downwardly through holes 71 and 44 and is screwed into threaded bore 32 of ferrule 30 to fasten the flooring panels 50 at corners 51 to pedestal 10. Disc 70 is countersunk around hole 71 to receive the head of bolt 80 such that the bolt 80 is flush with the upper surface of flooring panels 50. A typical floor panel has a thickness of about 30mm. It will be appreciated, therefore, that by utilizing pedestals as hereinbefore described a minimum total spacing between the sub-floor and the upper surface of the flooring panels of 50mm or less may be obtained. This represents a considerable improvement over pedestals of the prior art which could provide a minimum spacing of about 70mm. By using a pedestal as hereinbefore described having a plurality of incremental portions, a total spacing in excess of 500mm can be obtained.

Claims: CLAIMS; 1. A pedestal for a raised flooring system, which pedestal comprises base means and a head-cap supported by the said base means, which head-cap is adapted to carry one or more flooring panels; wherein the said base means includes a stack of one or more incremental portions, the number of incremental portions being determined by the required spacing of the one or more panels from a sub-floor on which the base means stands. 2. A pedestal as claimed in claim 1, wherein the pedestal further includes clamp means to provide a positive engagement of the one or more floor panels to the said base means. 3. A pedestal as claimed in claim 2, wherein the said clamp means comprises a ferrule and a retaining plate; wherein the ferrule is fastened to and extends upwardly from the base of the pedestal, and the retaining plate is placed over the said one or more panels and is held in place by a bolt which is fastened into the ferrule. 4. A pedestal as claimed in any preceding claim, wherein the said incremental portions are formed from chipboard or high quality load bearing chipboard. 5. A pedestal as claimed in any preceding claim, wherein each incremental portion has the same depth as each of the other incremental portions. 6. A pedestal as claimed in any preceding claim, wherein each incremental portion is generally rectangular or square in cross-section. 7. A pedestal as claimed in any preceding claim, wherein the said incremental portions are laminated together to form a consolidated base by interposing a layer of adhesive between each incremental portion and its neighbouring incremental portions. 8. A pedestal as claimed in any preceding claim, wherein the said incremental portions are secured together by means of mechanical fixings such as screws, nails or the like. 9. A pedestal as claimed in any preceding claim, wherein the stack is coated or covered with a fire resisting or fire retarding material. 10. A pedestal as claimed in claim 9, wherein the said fire resisting or fire retarding material is an aluminium foil. 11. A pedestal as claimed in any preceding claim, wherein the said head-cap is provided with one or more upstanding walls or nibs for locating one or more edges of the one or more floor panels. 12. A pedestal as claimed in any preceding claim, wherein the said head-cap is provided with depending walls which are arranged to engage the sides of said stack thereby to restrain the head-cap from rotation with respect to the said base. 13. A pedestal as claimed in any preceding claim, wherein the base means comprises one or more packing pieces or shims interposed between the top-most incremental portion and the said head-cap, thereby to adjust the total height of the head-cap above the said sub-floor. 14. A flooring system which comprises a plurality of pedestals as claimed in any preceding claim, and a plurality of flooring panels. 15. A flooring system as claimed in claim 14, wherein each flooring panel is supported on one or more of the said pedestals. 16. A flooring system as claimed in claim 14 or 15, wherein each pedestal supports or partially supports one flooring panel. 17. A flooring system as claimed in any of claims 14 to 16, wherein each pedestal is arranged to support the two or more panels at their sides or corners. 18. A flooring system as claimed in any of claims 14 to 17, wherein each pedestal is arranged partially to support four generally rectangular flooring panels, the flooring panels being placed over the array of pedestals such that each pedestal supports a corner of four neighbouring panels. 19. A flooring system as claimed in any of claims 14 to 18, wherein the upper surfaces of neighbouring flooring panels define a recess adapted to receive the retaining plate flush with the upper surface of the floor.

Inventors: FRANCIS PAUL, SPOONER JOHN, TIPSON FRANK, FRANCIS, PAUL, SPOONER, JOHN, TIPSON, FRANK
Applicants: DURABELLA LTD, DURABELLA LIMITED
Application year: 1992
Main classification: E04F15
IPC codes: E04F15