IE20090402A1 - Insulator for a floor assembly - Google Patents

Abstract

An acoustic insulating sheet (30) for a floor asssembly comprises a foam layer (40) of a mixture of open cell and closed cell foam particles, typically of reconstituted foam, and one or two moisture-proof layers (42,44), typically of polypropylene film, affixed to at least one of the upper and lower surfaces of the foam layer (40). The insulating sheet may also include an adhesive layer. The moisture-proof layer or layers (42,44) are factory bonded to the foam layer, and the sheet is supplied in roll form to a building site, where it may be used in a floor assembly (16) of a building structure (10). The floor assembly comprises an underlying floor layer (24) and an insulating layer comprising a number of insulating sheets (30) of the invention provided on the underlaying floor layer. The floor assembly includes a further flooring layer such as a screed (32) located on the insulating layer (30). The insulating sheets may be laid side by side in abutting relationship wihh each other, with the moisture-proof layer of a first sheet overlapping a second, adjacent sheet, to form a continuous moisture-proof layer. The insulating sheets (30) may turn up through 90 degrees at a wall (22) to acoustically insulate the flooring layer (32) of the floor assembly from the wall, without the need for any separate insulating flanking. <Figure1>

Description

’Insulator for a floor assembly” The present invention relates to an insulator for a floor assembly of a building structure. The insulator acoustically insulates part of the floor assembly from adjoining or adjacent walls, floors and ceiling^, used in building structure.

Continued legislative changes in the UK require more robu&acousticisolation elements, and greater soundproofing performance from the transmission of noise between separating floors (known as party floors) and adjoining wall systems.

It is known to reduce the passage of sound through a floor by using independent linings and/or floating treatments. Alternatively, unwanted sound transmission may be reduced by employing a higher-density wall and floor construction.

Such solutions are far from ideal, as high-density constructions have higher unit costs, due to their increased weight, which causes transportation and installation issues. Independent linings and floating treatments have been proven to have limitations in sound absorbing performance due to, e.g. installation difficulties, weight of materials, the need for additional flanking and isolating elements, and the isolating limitations of the products at varying frequencies. The known linings are rubber, rubber crumb, or a closed cell polyethylene foam. Rubber is substantially rigid and heavy. Closed cell polyethylene foam is also substantially rigid, is not waterproof, and tends to collapse over time.

According to a first aspect of the present invention there is provided an insulator for a floor assembly, the insulator comprising: a foam layer; and a moisture-proof layer affixed to at least one of the upper and lower surfaces of the foam layer.

The insulator may be an insulating sheet, that is, having a length and breadth considerably greater than its thickness.

The moisture-proof layer may be bonded, laminated, or fixed in any other way to the foam layer, e.g. by means of adhesives, heat or chemical reaction. The moisture-proof layer is affixed to the foam layer in a factory where the insulator is created, in contrast to affixing together a plurality of different elements at a building site.

By moisture-proof layer, we mean that moisture and water cannot penetrate the layer under normal conditions in use.

Typically, a respective moisture-proof layer is affixed to each of the upper and lower surfaces of the foam layer.

Typically, the moisture-proof layer comprises a thin film.

Typically, the moisture-proof layer comprises a polypropylene film.

Typically, the moisture-proof layer is much thinner than the foam layer. Optionally, the foam layer has a thickness of 3mm to 35mm. Typically, the foam layer has a thickness of 5mm to 25mm.

Typically, the moisture-proof layer is longer in extent than the foam layer in at least one direction, such that part of the moisture-proof layer overhangs the foam layer in that direction. 0 4 02 Hence, the surface areas of the moisture-proof layer and the foam layer are not the same, with the surface area of the moisture-proof layer being larger. By over-hang” we also include the meaning under-hang” in the case where the moisture-proof layer is located underneath the foam layer, in use.

This allows a first insulator to be located adjacent to a second insulator, with the over-hanging part of the moisture-proof layer of the first insulator over-lying the second insulator, to ensure the continuity of the moistureproof layer over the transition between the first and second insulators. Hence, no separate jointing element is needed, to cover the join between two insulators.

Optionally, the moisture-proof layer may be longer in extent than the foam layer in both width and breadth directions such that part of the moistureproof layer overhangs the foam layer on all sides.

Typically, the insulator is sufficiently flexible so as to bend through 90 degrees without breaking or cracking. This enables the insulator to be used to fully insulate the edges of a room (e g. the insulator can travel partly up an adjacent wall/vertical projection, such that a further flooring layer located on the insulator is fully insulated from that adjacent wall, as well as from the underlying floor). If not for this flexibility, the insulator would not be able to turn corners like this, and additional insulating flanking would be required to fully insulate a further (e.g. upper) floor layer from adjacent walls/vertical projections.

Typically, the insulator also includes an adhesive layer, for attaching the insulator to a floor or vertical surface. The adhesive layer may comprise 4 02 an adhesive backing or a self-adhesive backing. The adhesive layer may be formed integrally with the insulator.

Typically, the foam layer comprises a plurality of closed cell foam particles and a plurality of open cell foam particles. Such foams can have good acoustically insulating properties, for both impact and airborne sounds.

Preferably, the open cell and closed cell foam particles are mixed together in a substantially random orientation. Typically, said open cell foam particles and said closed cell foam particles are bonded together. The mixture of open and closed cell foam particles may comprise a composition of 10% to 90% by volume of said open cell particles, with the remainder being closed cell particles (i.e. at least 10% of both types of particles). Optionally, the ratio of open; closed cell foam particles is 10:90.

Typically, the foam layer comprises a reconstituted foam. Reconstituted foams formed from both open and closed cell particles have the advantage of being resilient. Hence, such reconstituted foams will bounce back if squashed, unlike a pure, closed cell foam. In contrast, if a closed cell foam is used as an insulator in a floor assembly, the closed cell foam becomes compressed by the load of the floor assembly over time, resulting in a gap between the skirting board and the top of the floor assembly, through which sound can then travel.

Reconstituted foams are flexible enough to turn corners without breaking, unlike, e g. rubber, and/or rubber crumb.

Also, reconstituted foams have better acoustic performance, thermal performance and dynamic stiffness compared to closed cell foams. θ 0 4 02 Preferably, the reconstituted foam is formed from an original virgin open cell foam. However, even virgin open cell foams, by their composition, contain both open and closed cells. This is because, when a virgin open cell foam block is being cured, some closed cells are formed in the cooler, peripheral regions of the foam block Hence, a block of virgin open cell foam includes a proportion of closed cell foam particles, formed in the peripheral regions of the block Typically, the reconstituted foam is made by taking one or more block(s) of virgin open cell foam, chopping these into foam chips, mixing the foam chips together in a random orientation, and the reconstituted foam is then rebonded together from these chips. Hence, the reconstituted foam which results includes both open cell foam particles, and closed cell foam particles, and it tends to have more open cell foam particles than closed cell foam particles.

The virgin open cell foam is typically polyether-polyurethane. The reconstituted foam which results from this is typically a mixture of varying densities of open and closed cell polyether-polyurethane foam chips. Alternatively, the virgin open cell foam could be other types of foam.

Alternatively, the foam layer may comprise a reconstituted foam formed from a mixture of open cell foam particles, which originated from a virgin open cell foam, and closed cell foam particles, which originated from a virgin closed cell foam (instead of the closed cell foam particles being a by-product of the formation of virgin open-cell foam). Such reconstituted foams can have any desired ratio of closed cells to open cells.

Reconstituted foams can provide superior acoustic insulating properties, as compared to virgin closed cell foams and/or rubber. Reconstituted fe ο 9 0 4 Q 2 foams have better dynamic stiffness, and will perform better than closed or open cell foam for structural loading.

The insulator is preferably an insulating sheet supplied in roll form for use in construction of a building structure.

According to a second aspect of the present invention there is provided a floor assembly fora building structure, the floor assembly comprising: an underlying floor layer; and an insulating layer provided on the underlying floor layer, wherein the insulating layer comprises at least one insulator according to the first aspect of the invention.

The insulating layer may be provided directly on the underlying floor layer, or it may be provided indirectly on the underlying floor layer, with one or more intermediate layers located there between.

Optionally, the underlying floor layer comprises a plurality of concrete floor planks. Optionally, the underlying floor layer may include infill blocks located between the planks.

Typically, the floor assembly comprises a party floor which separates a room above the floor assembly from a room below the floor assembly.

Optionally, the floor assembly includes a further flooring layer located on the insulating layer.

Optionally, the further flooring layer of the floor assembly comprises a screed layer. Optionally, the screed comprises a sand and cement mixture.

If the (or a) moisture-proof layer is the uppermost layer of the insulator, the moisture-proof layer prevents any moisture from the screed layer from penetrating the foam layer (which, if this occurred, could harm the acoustic properties of the foam layer).

Alternatively, the further flooring layer of the floor assembly comprises a hard/soft wearing surface, e g. carpet; linoleum; timber or laminate board; or ceramic, stone or clay tile. The further flooring layer is not limited to these.

Optionally, the floor assembly includes at least one intermediate layer located between the underlying floor layer and the insulating layer.

Optionally, the intermediate layer comprises a screed layer.

In such embodiments, if the (or a) moisture-proof layer is affixed to the lower surface of the foam layer, this prevents moisture from the screed layer from entering the foam layer of the insulator.

Typically, the insulating layer extends substantially continuously over the entire area of the underlying floor.

Typically, the insulating layer comprises a plurality of insulators according to the first aspect of the invention, laid side by side in abutting relationship with each other.

Typically, the moisture-proof layer of a first insulator overhangs the foam of the first insulator in at least one direction, and overlies a second, adjacent insulator, to form a continuous moisture-proof layer.

IE 0 904 02 Optionally, the over-hang part ofthe first moisture proof layer is adhered to the second insulator.

Typically, the moisture-proof layers of all insulators ofthe insulating layer overlie at least one, adjacent insulator, to form a continuous isolation layer.

According to a third aspect of the invention there is provided a building structure having a floor assembly ofthe second aspect ofthe invention, and at least one vertical projection extending through or on the floor assembly.

Optionally, the vertical projection comprises a wall.

Optionally, at the vertical projection, the insulating layer bends through 90 degrees and extends vertically at least part way up the vertical projection.

In the embodiments where a further flooring layer of the floor assembly is located on the insulating layer, typically, the vertical part ofthe insulating layer is located between the further flooring layer and the vertical projection. This acoustically insulates the further flooring layer of the floor assembly (e g. screed or hard/soft wearing surface) from the vertical projection of the building structure, without the need for any separate insulating flanking to achieve this.

Optionally, at the top of the further flooring layer of the floor assembly, the vertical part of the insulating layer bends through another 90 degrees, and runs at least some way horizontally back along the further flooring layer of the floor assembly. In some embodiments, this more completely insulates Ο 4 02 the further flooring layer of the floor assembly from the rest of the building structure. This also allows other components of the building structure (e.g. a skirting board and/or plaster board) to be located on the upper, horizontal part of the insulating layer. The insulating layer may thus extend between the further flooring layer and one or more elements fixed to the vertical projection, such as the skirting board and/or plaster board of the wall or other components of the building structure.

Optionally, a plurality of vertical projections may be provided, and the insulating layer may extend vertically at least part way up all of the vertical projections. The insulating layer may extend up all perimeter or adjoining structure, surfaces, or projections through or on the floor assembly.

According to a fourth aspect of the invention there is provided a floor assembly for a building structure, the floor assembly comprising: an underlying floor layer; an insulating layer provided on the underlying floor layer, wherein the insulating layer comprises at least one insulator according to the first aspect of the invention; and a wearing surface located directly on top of the insulating layer; wherein the insulating layer insulates the wearing surface from the underlying floor layer.

Typically, the wearing surface comprises carpet; linoleum; timber or 25 laminate board; or ceramic, stone or clay tile.

According to a fifth aspect of the invention there is provided a building structure having a floor assembly of the fourth aspect of the invention, and wherein the insulating layer is arranged to insulate the wearing surface from the rest of the building structure. 0402 Typically, the insulating layer is flexible, and has at least one 90 degree bend where the flooring assembly meets a vertical projection there from or there through, such that the insulating layer at least partially lines the vertical projection to insulate the wearing surface finish from that vertical projection of the building structure.

The fourth and fifth aspects of the invention may also include any features, essential or optional, of the first to third aspects of the invention.

Embodiments of the invention will now be described, by way of example only, and with reference to the following drawings, in which:Fig 1 shows a cross-sectional view of part of a building structure including 15 a floor assembly, which includes an insulator of the present invention; Fig 2 shows an area A of Fig 1 in more detail; Fig 3 shows part of the insulator of Fig 1 in more detail; Fig 4 shows the insulator of Fig 1 lying in an adjacent, abutting relationship to a second insulator of the present invention; Fig 5 shows a different building structure, which includes an alternative 25 embodiment of a floor assembly which incorporates the insulator of Fig 1; and Fig 6 shows another, different building structure, which includes a further alternative embodiment of a floor assembly which incorporates the insulator of Fig 1.

Referring now to Fig 1, this shows a cross-sectional view of part of a building structure 10. The building structure 10 is an apartment block.

The lower part of the drawing shows a first apartment 12, and the upper part of the drawing shows a second apartment 14. Separating the first and second apartments 12, 14 is a floor assembly 16 and a ceiling assembly 18. The floor assembly 16 forms the floor of the second apartment 14, whilst the ceiling assembly 18 forms the ceiling of the first apartment 12. Hence, the floor assembly 16 comprises a party floor. To the left in Fig 1 is a wall assembly 20, which comprises an external wall 22 of the apartment block.

Looking now in more detail, the external wall 22 is composed of aggregate blocks, which fit together with mortar there between, as is conventional. Four of these blocks are shown (22a-22d), each of which belongs to a different row of blocks. The aggregate blocks typically have a density of between 1,300-2,300 kg/m3.

The floor assembly 16 includes an underlying floor, which includes a plurality of precast concrete floor planks 24 (one shown). One end of the floor plank 24 is located between two rows of aggregate blocks 22b, 22c, such that the plank 24 is supported at that height by the external wall 22. The plank 24 is at least 150mm in height Optionally, the plurality of planks 24 are interspersed with aggregate infill blocks, supported by the planks 24.

Hence, the aggregate blocks 22a, 22b of the external wall 22 form a vertical projection extending on the underlying floor (the plank 24) of the floor assembly 16. 0 4 The ceiling assembly 18 comprises one or more layers of gypsum board 26 which are attached by Z-shaped brackets 28 to the underneath of the precast concrete floor plank 24, such that the ceiling assembly 18 is supported by the floor assembly 16. The details ofthe ceiling assembly 18 are not important to the invention.

On top of the plank 24 is a flexible insulator 30, which forms part of an insulating layer, and which will be described in more detail below. The floor assembly 16 also includes a further flooring layer, in the form of a screed layer 32, which is located on top of the flexible insulator 30 The screed layer 32 comprises a sand and cement mixture. Optionally, a hard/soft wearing surface (not shown) may be located on the screed layer 32 (e.g. carpet; linoleum; timber or laminate board; or ceramic, stone or clay tile).

The insulator 30 covers the part of the upper surface ofthe plank 24 that is shown in Fig 1, and extends as far as the aggregate block 22b of the external wall 22. At the aggregate block 22b, the insulator 30 turns upwards by 90 degrees and lines the side of the aggregate block 22b, separating the screed layer 32 from the aggregate block 22b. At the top of the screed layer 32, the insulator 30 turns another 90 degrees and travels back on itself, on top of the screed layer 32, away from the aggregate block 22b. Hence, the insulator 30 has a lower part 30a, (between the plank 24 and the screed layer 32), a vertical part 30b (between the screed layer 32 and the aggregate block 22b) and an upper part 30c (above the screed layer 32).

On top of the upper part 30c of the insulator 30 and parallel to the inner surface ofthe aggregate blocks 22, sits a sheet of plasterboard 34 (otherwise known as wallboard), which forms the internal surface ofthe ΙΕ Ο 9 ο 02 wall assembly 20. A series of battens 36 (one shown) mount the plasterboard 34 on the aggregate blocks 22, as is conventional in the art.

Also sitting on the upper part 30c of the insulator 30, and mounted to the inner face of the sheet of plasterboard 34 is a skirting board 38.

Since the insulator 30 is flexible enough to turn these two corners, no additional insulating flanking is required to fully insulate the screed layer 32 from the wall assembly 20 and from the rest of the floor assembly 16.

Fig 2 shows an enlarged portion of part of Fig 1, for greater clarity. Fig 2 also shows a second sheet of plasterboard 39, which is located between, and fixed to, the aggregate blocks 22 and the batten 36. The second sheet of plasterboard 39 also sits on the upper part 30c of the insulator 30.

Referring now to Fig 3, the insulator 30 is shown in more detail. The insulator 30 comprises a foam layer 40. In this embodiment, the foam layer 40 comprises a plurality of closed cell foam particles and a plurality of open cell foam particles, mixed together in a random orientation. The foam layer 40 comprises a reconstituted chip foam, formed from original, virgin, open cell foam. The reconstituted foam comprises a mixture of varying densities of open and closed cell polyether-polyurethane foam chips. The foam layer 40 has good acoustically insulating properties, for both impact and airborne sounds, and is flexible enough to turn the two 90 degree corners shown in Figs 1 and 2, without breaking or cracking. The foam layer 40 is resilient, and will bounce back after being compressed. The foam layer 40 has a typical thickness of 3mm to 35mm; usually between 5mm and 25mm. However, the invention includes foam layers 40 of any thickness.

The insulator 30 also includes a first moisture-proof layer 42 affixed to the upper surface of the foam layer 40, and a second moisture-proof layer 44 affixed to the lower surface of the foam layer 40. Each moisture-proof layer 42, 44 comprises a thin polypropylene film. The moisture-proof layers 42, 44 may be bonded, laminated, or fixed in any other way to the foam layer 40, e.g. by means of adhesives, heat or chemical reaction.

The moisture-proof layers 42, 44 are significantly thinner than the foam layer 40.

The first moisture-proof layer 42 is longer in extent than the foam layer 40 in at least one direction (to the right in Fig 3), such that a part 42h of the first moisture-proof layer 42 overhangs the foam layer 40 in that direction.

Hence, the surface areas of the moisture-proof layer 42 and the foam layer 40 are not the same, with the surface area of the moisture-proof layer 42 being larger. The first moisture-proof layer 42 is longer in extent than the foam layer 40 in both width and breadth directions, such that part of the first moisture-proof layer 42 overhangs the foam layer on all sides (only one side shown in Fig 3).

Optionally (not shown), the second moisture-proof layer 44 may also overhang the foam layer 40, in the same, or a different direction to the over-hang of the first moisture proof layer 42. Alternatively (not shown), the second moisture-proof layer 44 may overhang the foam layer 40, instead of the first moisture-proof layer overhanging.

The insulator 30 may also include a lower adhesive layer (not shown), for attaching the insulator 30 to the underlying floor, or other (e g. vertical) surface. The adhesive layer may comprise an adhesive backing ora self- 0 4 02 adhesive backing. The adhesive layer 42 may be formed integrally with the insulator 30.

Optionally, the moisture-proof layers 42, 44 comprise printable layers. For example, installation instructions may be screen-printed on these layers.

Fig 4 shows the insulator 30 lying in an adjacent, abutting relationship to a second, similar insulator 30'. The insulator 30' also has a foam layer 40', a first moisture-proof layer 42’ and a second moisture-proof layer 44'. The first moisture proof layer 42’ typically also has at least one overhanging part {not shown). It could, for instance, be provided on the right hand end ofthe insulator 30'. Alternatively or additionally, it could be provided at the left hand end ofthe insulator 30', but is folded back on top of itself so as not to overhang in this instance, or folded around the left hand end of the insulator 30' and tucked beneath the second moisture-proof layer 44’.

The moisture-proof layer 42 ofthe first insulator 30 overlying the second, adjacent insulator 30' provides a continuous moisture-proof layer across the transition between the insulators 30, 30'. Hence, no separate jointing element is needed, to cover the join between two insulators 30, 30’.

Optionally, the over-hang part 42h of the first moisture proof layer 42 is adhered to the second insulator 30'.

Hence, as illustrated in Fig 4, a plurality of insulators 30, 30' can be put together in abutting relationship in this way, to form a continuous insulating/isolation layer which extends substantially continuously over the entire area ofthe underlying floor. The larger the area of each insulator 30, the fewer insulators will be needed to cover the entire floor area.

Since the moisture proof layers 42 of adjacent insulators 30, 30' overlie IE 0 9 ο 4 ο 2 each other, the moisture-proofing is also continuous over the entire floor area Hence, in the embodiment of Figs 1 and 2, the first moisture-proof layer 42, being the upper layer of the insulator 30, prevents any moisture from the screed layer 32 (which lies on top of the insulator 30) from penetrating the foam layer 40 of the insulator 30. This preserves the acoustic properties of the foam layer 40.

Fig 5 shows an alternative building structure 100, in which like parts have like numbers, preceded by 100. In this embodiment, the relative positions of the insulator 30 and the screed layer 132 have been exchanged, so that the screed layer 132 lies directly on the underlying floor, and the insulator 30 lies directly on top of the screed layer 132. A further flooring layer 150 is located on top of the insulator 30. In this embodiment, the further flooring layer 150 comprises a wearing hard/soft surface, e.g. carpet; linoleum; timber or laminate board; or ceramic, stone or clay tile.

Hence, in this embodiment, the insulating layer (including the insulator 30) is provided indirectly on the underlying floor layer, with an intermediate layer (the screed layer 132) located between the insulator 30 and the underlying floor layer.

In the Fig 5 embodiment, it is useful if the second moisture-proof layer 44 overhangs the foam layer 40 of the insulator (either instead of, or in addition to the first moisture-proof layer 42 having an overhanging portion). Hence, the lowermost surface of the insulators 30 can provide a continuous, moisture-proof barrier against any seepage of moisture upwards from the screed layer 132. /£ 0 90 02 In the Fig 5 embodiment, the further flooring layer 150 and the insulator 30 both extend up to the sheet of plasterboard 134. The skirting board 138 is fixed to the sheet of plasterboard 134 and sits on top of the further flooring layer 150.

Fig 6 shows an alternative building structure 200, in which like parts have like numbers, preceded by 200. This arrangement is very similar to the Fig 5 arrangement, except that the skirting board 238 is not located on the further flooring layer 250, Instead, the skirting board 238 sits directly on the screed layer 232. The insulator 30 lines the upper surface of the screed layer 232 up to the skirting board 238. When the insulator 30 abuts the skirting board 238 it turns upwards through 90 degrees and proceeds vertically up the skirting board 238, for a proportion of the height of the skirting board 238 (equal to the height of the further flooring layer 250). The upper end of the insulator 30 is then topped with a bead 252 (e.g. of wood), for aesthetic effect Hence, the vertical part of the insulator 30 is located between the further flooring layer 250 and a vertical projection (the skirting board 238). This acoustically insulates the further flooring layer 250 (the wearing hard/soft surface) from the wall assembly 220 and from the rest of the floor assembly 216. This acoustic insulation has been achieved without the need for any separate insulating flanking.

The Fig 1 embodiment provides a one part acoustic isolation layer for a floating screed, to isolate the underlying floor layer (the party sub-floor) from impact sound transmission. The embodiments of Figs 5 and 6 provide a one-part acoustic isolation layer for soft and hard surface finishes, to isolate the underlying floor layer (the party sub-floor) from impact sound transmission. All embodiments can include integral flanking and jointing, and provide a robust product. Other advantages include being lightweight, good acoustic performance, good thermal performance and dimensional stability.

In all embodiments, although only one edge of the room is shown, the same arrangement would typically be repeated at all edges of the room, where walls meet the floor. Also, a similar edge arrangement can be used in the middle of the room, away from the walls, if there are other vertical projections through or on the party floor (e g. an island in the middle of a kitchen) Hence, in some embodiments, like shown in Figs 1, 2 and 6, a plurality of vertical projections may be provided, and the insulating layer may extend vertically at least part way up all of the vertical projections.

A further advantage lies in that the insulator 30 is a single product, whereas in other systems, a number of different elements need to be adhered together at the building site, to provide the required isolation (e.g. a first insulating layer to cover the floor, and separate flanking/jointing).

Modifications and improvements may be incorporated without departing from the scope of the invention. For example, the building structure 10 is not necessarily an apartment block. Instead, the building structure may be a house, with a ceiling/floor separating the ground floor from the first floor (or the first floor from the second floor, etc.).

All materials and dimensions given are examples only.

Additional layers beyond those shown here may be incorporated into the flooring structure, either above, below, or between the layers shown.

Hence, in general, where we describe one layer being on top of another Θ2 layer, we include the meaning “indirectly on top of with an intermediate layer in between.

Claims (25)

1. An insulating sheet for a floor assembly, the insulating sheet comprising: a foam layer; and at least one moisture-proof layer affixed to at least one of the upper and lower surfaces of the foam layer.

2. An insulating sheet according to claim 1, wherein a respective moistureproof layer is affixed to each of the upper and lower surfaces of the foam layer.

3. An insulating sheet according to any preceding claim, wherein the or each moisture-proof layer comprises a polypropylene film.

4. An insulating sheet according to any preceding claim, wherein the foam layer has a thickness of 5mm to 25mm.

5. An insulating sheet according to any preceding claim, wherein the or each moisture-proof layer is longer in extent than the foam layer in at least one direction, such that part of the moisture-proof layer overhangs the foam layer in that direction.

6. An insulating sheet according to any preceding claim, further including an adhesive layer, for attaching the insulator to a floor or vertical surface.

7. An insulating sheet according to any preceding claim, wherein the foam layer comprises a plurality of closed cell foam particles and a plurality of open cell foam particles.

8. An insulating sheet according to any preceding claim, wherein the foam layer comprises a reconstituted foam.

9. An insulating sheet according to claim 8, wherein the reconstituted foam is a mixture of varying densities of open and closed cell polyetherpolyurethane foam chips.

10. An insulating sheet according to claim 8, wherein the reconstituted foam is formed from a mixture of open cell foam particles, which originated from a virgin open cell foam, and closed cell foam particles, which originated from a virgin closed cell foam.

11. An insulating sheet according to any preceding claim, supplied in roll form.

12. A floor assembly for a building structure, the floor assembly comprising: an underlying floor layer; and an insulating layer provided on the underlying floor layer, wherein the insulating layer comprises at least one insulating sheet according to any of claims 1 to 11.

13. A floor assembly according to claim 12, wherein the floor assembly includes a further flooring layer located on the insulating layer.

14. A floor assembly according to claim 13, wherein the further flooring layer of the floor assembly comprises a screed layer.

15. A floor assembly according to claim 13, wherein the further flooring layer of the floor assembly comprises one of carpet; linoleum; timber; laminate board; ceramic tile; stone tile; and clay tile. 5

16. A floor assembly according to any of claims 13 to 15, wherein the further flooring layer is a wearing surface located directly on top of the insulating layer; and wherein the insulating layer insulates the wearing surface from the underlying floor layer.

17. A floor assembly according to any of claims 12 to 16, wherein the floor assembly includes at least one intermediate layer located between the underlying floor layer and the insulating layer. 15

18. A floor assembly according to claim 17, wherein the intermediate layer comprises a screed layer.

19. A floor assembly according to any of claims 12 to 18, wherein the insulating layer comprises a plurality of insulating sheets according to the 20. First aspect of the invention, laid side by side in abutting relationship with each other, such that the moisture-proof layer of a first insulating sheet overhangs the foam of the first insulating sheet in at least one direction, and overlies a second, adjacent insulating sheet, to form a continuous moisture-proof layer.

20. A floor assembly according to claim 19, wherein the over-hang part of the first moisture proof layer is adhered to the second insulating sheet.

21. A building structure having a floor assembly according to any of claims 30 12 to 20, and at least one vertical projection adjacent to or on the floor assembly, wherein the insulating layer bends through 90 degrees and extends vertically at least part way up the vertical projection.

22. A building structure according to claim 21, wherein the floor assembly includes a further flooring layer located on the insulating layer, and wherein the vertical part of the insulating layer is located between the further flooring layer and the vertical projection.

23. A building structure according to claim 22, wherein at the top of the further flooring layer of the floor assembly, the vertical part of the insulating layer bends through another 90 degrees, and runs at least some way horizontally back along the further flooring layer of the floor assembly.

24. A building structure according to claim 23, wherein the insulating layer extends between the further flooring layer and one or more elements fixed to the vertical projection.

25. A building structure according to any of claims 22 to 24, wherein the floor assembly includes a wearing surface located directly on the insulating layer, and wherein the insulating layer at least partially lines the vertical projection to insulate the wearing surface from the vertical projection of the building structure.