GB2261233A

GB2261233A - Acoustically insulating flooring element and floor composed of such elements

Info

Publication number: GB2261233A
Application number: GB9123772A
Authority: GB
Inventors: John Leslie Mark; Ronald Brian Parker
Original assignee: Parker Mark & Associates Limit
Current assignee: Parker Mark & Associates Limit
Priority date: 1991-11-08
Filing date: 1991-11-08
Publication date: 1993-05-12
Also published as: GB9123772D0

Abstract

An acoustically insulating floor element (10) consists of a rigid surfacing member (11) of chipboard or other suitable solid mass material, a metallic plate (12) bonded at one of its major faces to the surfacing member (11), and a resilient base member (13) of rockwool or other fibrous material bonded to the other major face of the plate. The acoustic insulating properties of the plate in relation to its thickness are such about the adjoining surfacing and base members can be relatively thin, so as to permit a floor to be constructed from such members without excessive increase in height above an existing floor surface. The fibrous material may have the fibres arranged substantially perpendicularly to the plane of the plate. <IMAGE>

Description

ACOUSTICALLY INSULATING FLOORING ELEMENT AND FLOOR COMPOSED OF SUCH ELEMENTS The present invention relates to an acoustically insulating flooring element and to a floor composed of a number of such elements.

Increasing attention is being paid to the need to achieve adequate acoustic insulation of floors in multi-level buildings, particularly residential buildings and office buildings. Regulations exist to set minimum acoustic insulation standards for newly constructed buildings and the basic structural conditions necessary for meeting these standards can, by and large, be taken into account in the initial building design. There is much less latitude for accommodating these conditions, however, in the case of conversion or reconstruction of older buildings, and regulatory standards do not yet apply to buildings in this category. Nevertheless, the damping of noise transmission between floors is just as much a problem for old buildings as for new, and inadequate acoustic insulation can be a source of considerable discomfort for occupiers.

The effectiveness of floor acoustic insulation is tested by reference to airborne sound transmission and impact sound transmission, with established test criteria for the level of transmission to the room or space below the insulated floor.

Existing methods of providing insulated floors sometimes address both forms of sound transmission, but often only one or the other. A factor common to most insulated floors able to provide satisfactory damping of both airborne and impact sound transmission is excessive floor thickness, which leads to major problems with overall floor height, for example the need to raise skirtings, trim doors, adjust stairs and effect other changes to ensure compatability of fixtures with the level of the floor surface. The usual practice is to place overlay panels of chipboard or fibreboard, with a thickness of 50 millimetres or more, on an existing floor and to insert sound absorbing fibrous material between the floor joists. Insertion of the sound absorbing material requires the original floorboards to be taken up and relaid.In some cases the original floor structure may have insufficient cavity space for this material and it is then necessary to create a cavity structure from a framework of battens.

Such insulation procedures, particularly for older buildings, are labour-intensive and time-consuming and frequently achieve adequate insulation only at the expense of significantly increased floor heights.

It is accordingly the principal object of the present invention to provide an acoustically insulating flooring element, and a floor constructed from such elements, that may be largely free from the disadvantages of the prior art insulating methods and in particular may be suitable for use in both old and new buildings and able to achieve acceptable acoustic insulation properties for only a modest increase in floor height.

Other objects and advantages of the invention will be apparent from the following description.

According to the present invention there is provided an acoustically insulating flooring element comprising a rigid surfacing member of solid mass material, a plate of metallic material bonded at one major face thereof to the surfacing member, and a resilient base member of fibrous material bonded to the other major face of the plate.

In such a flooring element the features of strength, acoustic insulation and footstep cushioning effect are combined into a single unit or module with an overall thickness which need not exceed substantially 40 millimetres and preferably is in the region of 32 millimetres. The metallic plate has a relatively high acoustic insulating capability in relation to its thickness and allows the adjoining layers, in effect a mass member for strength and a cushioning member for limited yield under footstep pressure and for additional acoustic insulation, to be correspondingly thinner. For example, the ratio of the plate thickness to the surfacing member thickness can be in the range of 1:30 to 1:40 and the ratio of the plate thickness to the resilient member thickness in the range of 1:20 to 1:30.The compact depth dimension of the element means that, when overlaid on an existing floor, the relatively small increase in height of the floor surface will cause little or no disruption to existing fixtures and realignment of skirtings will not always be necessary. The laying of the elements is a straightforward carpentry task and there is no need to disturb existing flooring.

The rigid surfacing member of the flooring element is preferably of wood or a wood-based composite material, such as chipboard, which provides mass and the required strength. The fibrous material of the resilient member, which contributes both acoustic insulation and a degree of yield, can be rockwool and preferably has its fibres aligned substantially perpendicularly to the plane of the adjoining face of the plate. This alignment of the fibres resists compression of the fibrous material, which could lead to a reduction in resilience and acoustic absorption capability as well as to unevenness in the floor surface. The plate, for reasons of cost and strength, is preferably of steel. The constituent parts of the element are normally available building or engineering materials, which facilitates low-cost production of the element.

The invention also provides an acoustically insulating floor comprising a plurality of flooring elements each as defined above, the elements being arranged to be contiguous at edges thereof to form a gapless covering layer with the surfacing members of the elements disposed uppermost and in a common plane A preferred embodiment of the invention will now be more particularly described, by way of example only, with reference to the accompanying drawing, the single figure of which is a schematic sectional view of a flooring element embodying the invention.

Referring now to the drawing, there is shown an acoustically insulating flooring element 10 which comprises a rigid surfacing member 11 of chipboard, intended to be uppermost in use, a steel plate 12 glued at its upper face to the member 11, and a resilient base member 13 of rockwool glued to the lower face of the plate 11.

The surfacing member 11 has a thickness of 18 millimetres, the plate 12 has a thickness of 0.5 millimetres and the base member 13 a thickness of 12 to 14 millimetres. These dimensions, which can be varied according to need or to commercial availability of sheet thickness of the constituent parts, typically result in an overall thickness of the element of substantially 32 millimetres.

The three laminae of the element individually have acoustic insulating properties, but the steel plate 12 has particularly effective sound absorbing and sound reflecting capabilities in relation to its thickness. The plate 12 and rigid surfacing member 11 together provide the strength necessary to accept typical floor loadings, particularly from heavy articles of furniture, and the resilient member 13 additionally contributes a degree of yield or cushioning so that there will be a comfortable reaction to walking on a floor composed of the elements.

The rockwool, which can have a weight of 100 kilograms per square metre, is structured with its fibres aligned vertically as indicated by dashed lines in the drawing. This alignment resists compression of the fibrous body and consequent decrease in cushioning and sound-absorbing capabilities.

The members 11 and 13 and plate 12 can be bonded together by any suitable glue, such as polyvinyl acetate adhesive.

The construction of a floor from a number of the elements 10 is carried out by laying the members edge-to-edge on an existing floor surface with the surfacing members 11 uppermost and in a common plane. The elements can be fixed in position by, for example, gluing to the existing floor surface. Individual elements can be cut for adaptation to the outline shape of the floor area and the completed floor can, if desired, be carpeted in normal manner.

Claims

1. An acoustically insulating flooring element comprising a rigid surfacing member of solid mass material, a plate of metallic material bonded at one major face thereof to the surfacing member, and a resilient base member of fibrous material bonded to the other major face of the plate.

2. A flooring element as claimed in claim 1, wherein the solid mass material of the surfacing member is wood or a wood-based composite material.

3. A flooring element as claimed in claim 2, wherein the composite material is chipboard.

4 A flooring element as claimed in any one of the preceding claims, wherein the fibrous material of the base member has its fibres aligned substantially perpendicularly to the plane of said other major face of the plate.

5. A flooring element as claimed in any one of the preceding claims, wherein the fibrous material of the base member is rockwool.

6. A flooring member as claimed in any one of the preceding claims, wherein the metallic material of the plate is steel.

7. A flooring element as claimed in any one of the preceding claims, wherein the plate is bonded to each of thesurfacing member and the base member by gluing.

8. A flooring member as claimed in any one of the preceding claims, wherein the element has a maximum thickness of substantially 40 millimetres.

9. A flooring element as claimed in claim 8, wherein the element has a thickness of substantially 32 millimetres.

10. A flooring element as claimed in any one of the preceding claims, wherein the ratio of thickness of the plate to the thickness of the surfacing member is in the range of 1:30 to 1:40.

11. A flooring element as claimed in any one of the preceding claims, wherein the ratio of thickness of the plate to the thickness of the base member is in the range of 1:20 to 1:30.

12. A flooring element substantially as hereinbefore described with reference to the accompanying drawing.

13. An acoustically insulating floor comprising a plurality of flooring elements each as claimed in any one of the preceding claims, the elements being arranged to be contiguous at edges thereof to form a gapless covering layer with the surfacing members of the elements disposed uppermost and in a common plane.