FIELD OF TECHNOLOGY

[0001] The present invention relates to an insulation sheet, and more particularly but not solely to a pliable laminate sheet for use as a building wrap.

BACKGROUND

[0002] In construction of buildings, it is desirable to prevent the ingress of water in either or both of liquid and vapour forms into the building structure. Water ingress may be due to weather, but particularly also may be caused by pressure differences between the external environment and the inside of a building.

[0003] The structural framing of a building may be covered in a building wrap to inhibit water ingress. The wrap may be provided in the form of solid planar panels, or a flexible wrap which may be provided in a roll and wrapped around the outside of the building. Some building wraps may be made from asphalt-impregnated paper; newer building wraps may be made of laminates of woven or non-woven polypropylene and plastic films.

[0004] In addition to prevention of water ingress, it may be desirable to allow controlled air movement into and out of the building, and the transport of moisture out of the building.

[0005] In particular, it may be desirable to allow for moisture transport out of the building, while maintaining a high standard of resistance to the ingress of water in at least liquid, or both liquid and vapour forms.

[0006] A building wrap may be required to incorporate other properties, such as fire resistance and insulation. It may also be required to provide light and particularly UV protection. In addition to these properties, a building wrap may need to be tough to enable efficient assembly, and resist tearing or disintegration against mechanical forces and/or the elements if it is left exposed before the building is clad. Finally, a building wrap may be desired to provide insulative properties, to increase the thermal efficiency of the building.

[0007] It may be desirable that a building wrap provides these additional properties without compromising its watertightness and breathability to air and water vapour.

[0008] It is an object of the invention provide a pliable insulation sheet which addresses or ameliorates one or more disadvantages or limitations mentioned above or associated with the prior art, or at least to provide the public with a useful choice.

SUMMARY

[0009] In a first aspect, the present invention may be said to broadly comprise a pliable insulation sheet having a plurality of layers, the sheet comprising a perforated insulating layer, a non-perforated water vapour permeable layer, and interposed between and bonding together at least two layers of the sheet, a non-perforated water vapour permeable adhesive. [0010] In another aspect, the plurality of layers may further comprise a first reinforcing layer and a second reinforcing layer.

[0011] In another aspect the first reinforcing layer, the second reinforcing layer, and the permeable layer may be arranged in a permeable unit, wherein the permeable unit may be arranged such that the first reinforcing layer is adjacent a first side of the permeable layer, and the second reinforcing layer is adjacent a second side of the permeable layer.

[0012] In another aspect, a first side of the insulating layer may be bonded to either the first reinforcing layer or the second reinforcing layer of the permeable unit by the adhesive.

[0013] In another aspect, the plurality of layers may further comprise a perforated foil layer.

[0014] In another aspect, the foil layer may be bonded to a second side of the insulating layer by an adhesive which is perforated.

[0015] In another aspect, the plurality of layers may further comprise a perforated woven polymer layer.

[0016] In another aspect, a first side of the woven polymer layer may be bonded to a second side of the insulating layer by a layer of extruded polymer, wherein the extruded polymer may be perforated, and a first side of the foil layer may be bonded to a second side of the woven polymer layer by an adhesive which is perforated.

[0017] In another aspect, the plurality of layers may further comprise a perforated woven polymer layer.

[0018] In another aspect, the perforated woven polymer layer may be bonded to a second side of the insulating layer by the adhesive.

[0019] In another aspect, the plurality of layers may further comprise a third reinforcing layer, and a second permeable layer.

[0020] In another aspect, a first side of the third reinforcing layer may be bonded to a second side of the insulating layer by the adhesive, and a first side of the second permeable layer may be adjacent a second side of the third reinforcing layer.

[0021] In another aspect, the plurality of layers may further comprise a perforated foil layer.

[0022] In another aspect, a first side of the foil layer may be bonded to either the first reinforcing layer or the second reinforcing layer of the permeable unit by the adhesive.

[0023] In another aspect, the insulating layer may be bonded to a second side of the foil layer by an adhesive, wherein the adhesive is perforated.

[0024] In another aspect, the insulation sheet may be for use as a construction membrane. [0025] In another aspect there may be provided an insulation sheet comprising: at least one insulating layer, and at least one permeable unit, wherein the at least one insulating layer and the at least one permeable unit are bonded together by a permeable adhesive.

[0026] In another aspect there may be provided a pliable insulation sheet comprising: a perforated insulating layer, and a permeable unit comprising a non-perforated water vapour permeable layer, wherein the insulating layer and the permeable unit are bonded together by a water vapour permeable adhesive.

[0027] In another aspect there may be provided a method of manufacturing a pliable insulation sheet comprised of a plurality of layers, the method comprising: providing an insulating first layer, the at least one insulating first layer being perforated, providing a permeable second layer, the second layer being non-perforated and water vapour permeable, and bonding at least two layers of the sheet together using an adhesive that, when set, is water vapour permeable.

[0028] In another aspect, the at least one insulating layer may comprise an insulating material comprising at least one of the following: a cross-linked structure, a closed cell structure, and/or a foam structure.

[0029] In another aspect, the insulating material may comprise at least one of a crosslinked polyethylene foam and/or expanded polyethylene foam.

[0030] In another aspect, the at least one insulating layer may comprise a thickness of about 1 mm to about 100 mm and/or a mass per area of the panel of about 2 to about 5,000 g/m ² .

[0031] For example, where the insulating layer has a thickness of about 4 mm it may have a mass per area of the panel of about 200 g/m ² .

[0032] As a further example, where the insulating layer has a thickness of about 100 mm it may have a mass per area of the panel of about 5,000 g/m ² .

[0033] In another aspect, the first reinforcing layer and/or the second reinforcing layer may comprise a non-woven material.

[0034] In another aspect, the first reinforcing layer and/or the second reinforcing layer may comprise a woven material that is optionally a polymeric woven material.

[0035] In another aspect, the permeable layer may comprise a thickness of about 5 to about 500 g/m ² .

[0036] In another aspect, the insulation sheet may be UV resistant.

[0037] In another aspect, the adhesive may define a contiguous layer between at least two layers.

[0038] In another aspect, the adhesive may be a thermosetting adhesive.

[0039] In another aspect, the adhesive may comprise a mass per area of the sheet of about 5 to about 350 g/m ² . [0040] In another aspect, the foil layer comprises a mass per area of the sheet of about 5 to about 250 g/m ² .

[0041] In another aspect, the polyethylene extrudate layer may comprise a mass per area of the panel of about 5 to about 350 g/m ² .

[0042] In another aspect, the permeable layer may comprise a breathable micro porous film.

[0043] In another aspect, a pliable insulation sheeting comprises a fibrous insulation layer and a water vapour permeable but liquid water impermeable second layer and interposed therebetween a discontinuous layer of an adhesive, such that at least some portions of the fibrous insulation layer and second layer are exposed to each other.

[0044] The second layer is non-perforated.

[0045] The pliable insulation sheeting includes a perforated third layer between the second layer and the adhesive, wherein at least some portions of the fibrous insulation layer and second layer are exposed to each other through both discontinuous portions of the adhesive and the perforations of the third layer.

[0046] The pliable insulation sheeting includes a liquid water permeable woven layer between second layer and the adhesive, wherein at least some portions of the fibrous insulation layer and second layer are exposed to each other through discontinuous portions of the adhesive and the liquid water permeable woven layer.

[0047] The pliable insulation sheeting is manufactured by spraying the adhesive onto the fibrous insulation layer and placing the fibrous insulation layer and any adjacent layer into contact with each other.

[0048] The term "axis" as used in this specification means the axis of revolution about which a line or a plane may be revolved to form a symmetrical shape. For example, a line revolved around an axis of revolution will form a surface, while a plane revolved around an axis of revolution will form a solid.

[0049] As used herein the term "and/or" means "and" or "or," or both.

[0050] As used herein "(s)" following a noun means the plural and/or singular forms of the noun.

[0051] For the purposes of this specification, the term "plastic" shall be construed to mean a general term for a wide range of synthetic or semisynthetic polymerization products, and generally consisting of a hydrocarbon-based polymer.

[0052] For the purpose of this specification, where method steps are described in sequence, the sequence does not necessarily mean that the steps are to be chronologically ordered in that sequence, unless there is no other logical manner of interpreting the sequence. [0053] The term "comprising" as used in the specification and claims means "consisting at least in part of." When interpreting each statement in this specification that includes the term "comprising," features other than that or those prefaced by the term may also be present. Related terms "comprise" and "comprises" are to be interpreted in the same manner.

[0054] This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

[0055] To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.

[0056] Other aspects of the invention may become apparent from the following description which is given by way of example only and with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which:

[0058] Figure 1 is a partially exploded view through a cross-section of a wall showing framing with a wall board and pliable insulation sheet.

[0059] Figure 2A is a cross-sectional view of an embodiment of a pliable insulation sheet.

[0060] Figure 2B is an exploded cross-sectional view of the pliable insulation sheet of Figure 2A.

[0061] Figure 3A is an exploded cross-sectional view of a permeable unit.

[0062] Figure 3B is an is a non-exploded view of the permeable unit of Figure 3A.

[0063] Figure 4A is an exploded cross-sectional view of an embodiment of a pliable insulation sheet.

[0064] Figure 4B is a non-exploded view of the pliable insulation sheet of Figure 4A.

[0065] Figure 5 is an exploded cross-sectional view of an embodiment of a pliable insulation sheet.

[0066] Figure 6 is an exploded cross-sectional view of an embodiment of a pliable insulation sheet.

[0067] Figure 7 is an exploded cross-sectional view of an embodiment of a pliable insulation sheet. [0068] Figure 8 is an exploded cross-sectional view of an embodiment of a pliable insulation sheet.

[0069] Figure 9 is an exploded cross-sectional view of an embodiment of a pliable insulation sheet.

[0070] Figure 10 is an exploded cross-sectional view of an embodiment of a pliable insulating sheet that includes a fibrous insulation layer.

DETAILED DESCRIPTION

[0071] With reference to the figures, in which similar features are generally indicated by similar numerals, an insulation sheet for use as a building wrap will be described.

[0072] In at least some preferred embodiments the insulation sheet is pliable or flexible and able to be bent. The pliable sheet may be provided for use in a roll and unrolled in order to be attached to the building.

[0073] Figure 1 is a partial section through the wall of a building, with the sectioned components shown partially exploded. As seen in Figure 1 , the building 1 has a frame 2, such as a timber or steel frame for example. A wall board 3, such as a friable gypsum wall board, is to be attached to an inside of the framing to define the inside of the building. A pliable insulation sheet 10 according to an embodiment of the disclosure is illustrated on the opposed external face of the framing 2.

[0074] While described with reference to Figure 1 as being applied to the external side of the framing of a wall, the sheet of the disclosure may additionally or alternatively be applied to the internal side of the framing of a wall. It may also be applied to other structure surfaces, such as to an underfloor area or roof to act as a weather barrier.

[0075] The pliable insulation sheet 10 of the disclosure is a laminate of at least two layers of material.

[0076] In at least some configurations, the pliable insulation sheet may be formed from one or more layers which are perforated. Where a layer does not otherwise have the necessary permeability properties, the layer may be perforated to provide passages through the layer.

[0077] At least two layers of the pliable insulation sheet are bonded together using an adhesive. The adhesive, when set, is water vapour permeable.

[0078] At least one layer of the insulation sheet is not perforated. Accordingly, a pliable insulation sheet may be provided which is water vapour permeable, but which is not fully perforated through its thickness. Such a configuration may provide increased water ingress resistance relative to a sheet which has perforations through its thickness.

[0079] The pliable insulation sheet may additionally include one or more layers which are not perforated but are permeable. The material of such a layer may have pores in it that provide for passage of air and/or vapour through the layer. [0080] Figure 2A illustrates a cross-sectional view through an embodiment of a pliable insulation sheet 10, and Figure 2B illustrates the pliable insulation sheet 10 of Figure 2A in an exploded form.

[0081] As shown in Figures 2, the pliable insulation sheet 10 comprises an insulating layer

11 to increase the insulative properties of the sheet 10. The insulating layer 11 may be provided of any known thermally insulating material, but in at least some described embodiments may be a foam, and particularly an expanded closed-cell foam. For example, the insulating layer 11 may be or include an expanded polyethylene foam (EPE) or more particularly a chemically crosslinked expanded polyethylene foam (for example products such as XPE, XLPE, and PEX).

[0082]

[0083] Where the foam is a closed-cell foam, or the insulating material does not have pores such as to allow water vapour transfer across it, the insulating layer 11 may be perforated to form passages for water vapour transfer.

[0084] In some configurations the insulating layer may have a thickness of about 1 to about 100 mm.

[0085] In some forms the insulating layer 11 of embodiments described herein may be provided by a fibrous insulation material.

[0086] The pliable insulation sheet 10 of Figure 2 has a second layer 12. The second layer

12 is not perforated but is water vapour permeable.

[0087] The second layer 12 may be a breathable micro-porous film. In some configurations the breathable micro-porous film may comprise a plastic material.

[0088] Where the second layer 12 is a breathable micro-porous film, it may be made of a predominantly polyethylene-polypropylene blend. The micro-porous film may have pores through its thickness.

[0089] The micro-porous film may be stretched during manufacture to increase the size of the pores in it.

[0090] The second layer may have a mass per unit area of about 5 to about 75 g/m ² . In some configurations the second layer may have a mass per unit area of about 5 to about 75 g/m ² .

[0091] The insulating layer 11 and second layer 12 are bonded together using an adhesive 13. As shown in Figures 2A and 2B, the adhesive defines a continuous non-perforated layer between the insulating layer 11 and second layer 12.

[0092] The pliable insulation sheet 10 of Figure 2A accordingly provides a building wrap which breathes, allows for water vapour transfer across it, provides insulation, and also provides high resistance to the ingress of liquid water. In the sheet 10 of Figure 2A the perforated insulating layer 11 may provide limited resistance to the ingress of liquid water relative to the adhesive 13 or the second layer 12, and liquid water may be able to pass through the perforations through the layer. However, the non-perforated adhesive 13, and the non-perforated second layer 12, may provide a higher level of resistance to liquid water ingress.

[0093] While described in relation to Figures 2A and 2B as bonding together two layers, one of which is perforated and one of which is non-perforated but water vapour permeable, in other forms a water vapour permeable adhesive may be used to bond together only perforated layers. In such configurations, the resistance of the panel to liquid water ingress may be provided primarily or solely by the set adhesive.

[0094] As illustrated in Figure 2A, the function of the sheet 10 utilising the non-perforated but permeable adhesive 13 and optionally a non-perforated but permeable second layer 12 is to provide a pliable insulation sheet 10 which may repel the ingress of liquid water, as illustrated by the arrow 31 but be permeable to air and water vapour, as illustrated by the arrow 32.

[0095] A layer of the adhesive 13 may preferably be of sufficient thickness to bond together the two layers between which the adhesive is interposed. However, in some configurations, the thickness of the adhesive may be provided in excess of what is required to hold the adjacent layers together, in order to provide desired levels of water vapour permeability and resistance to liquid water passing through the layer. In some configurations, the adhesive 13 may have a mass per area of about 5 to about 150 g/m ² . In some configurations, the adhesive may have a mass per area of about 35 to about 80 g/m ² .

[0096] In configurations where the pliable insulation sheet comprises a layer, other than an adhesive layer, which is non-perforated but water vapour permeable, the layer may be lapped on one or both sides by another layer to increase its resilience. The lapping layer or layers may have perforations or an otherwise non-solid cross-section so as to expose parts of the non-perforated and water vapour permeable layer, but may provide one or more of relatively increased structural rigidity, surface hardness, or tear or abrasion resistance.

[0097] Figure 3A illustrates an exploded view of a permeable unit 14 which comprises a non-perforated but permeable layer 12 that is lapped on both sides by reinforcing layers 15 and 16.

[0098] The reinforcing layers 15 and 16 may be the same as each other or may be different.

[0099] The reinforcing layers 15 and 16 may be in the form of a mesh with regular through- holes to expose the material of the underlying layer 12. The through-holes may comprise a significant proportion of the surface area of the reinforcing layers. For example, in some configurations the through-holes may comprise about 20% to about 60% of the surface of the reinforcing layers.

[0100] The reinforcing layers of a sheet may be either woven or non-woven layers. Both a woven and non-woven reinforcing layer may be made from materials including polymer materials and fibrous materials. In various preferred forms the reinforcing layers of a sheet are non-woven layers, and particularly non-woven layers made of a polymer material.

[0101] In some configurations the mass per unit area of the reinforcing layers 15 and 16 may be about 5 to about 250 g/m ² .

[0102] The one or more reinforcing layers 15 and 16 of the permeable unit 14 may be bonded to the permeable layer 12 by an adhesive. The adhesive may be the same as the water vapour permeable adhesive 13.

[0103] In other configurations, the layers of the permeable unit 14 may be fused together by heat, such as by direct thermal welding or ultrasonic welding.

[0104] A pliable insulation sheet according to the disclosure may include one or more permeable units 14.

[0105] Figure 4A is an exploded cross-sectional view of a configuration of a pliable insulation sheet 10. The sheet 10 has an insulating layer 11 which is lapped on one side by the permeable unit 14 described in reference to Figures 3. The insulating layer 11 and one of the reinforcing layers 15 or 16 of the permeable unit are bonded to each other by a layer of the permeable adhesive 13.

[0106] Figure 4B shows the layers of the insulation sheet 10 when joined together to form the sheet.

[0107] The pliable insulation sheet of the disclosure may include one or more further layers to provide additional desired functionality to the sheet.

[0108] For example, the sheet may include one or more foil layers. The one or more foil layers may be a low emissivity material that provides radiative insulating properties. For example, in some configurations the one or more foil layers may each be a metal foil, or more particularly, an aluminium foil.

[0109] Given the radiative insulating properties of the one or more foil layers it may be desirable to provide the foil at one or both outer faces of the pliable insulating sheet. The foil may however also, or alternatively, be provided as an internal layer of the sheet. In some configurations the one or more foil layers may be punched or perforated to provide vapour permeability through it.

[0110] In some configurations the mass per unit area of the one or more foil layers may be about 5 to about 250 g/m ² .

[0111] Additional layers may further include one or more woven layers. The one or more woven layers may be a woven polymer or non-polymer material.

[0112] The material comprising the one or more woven layers may offer various desirable properties. For example, in some configurations the one or more woven layers may comprise a material that is resistant to edge tear. In some configurations the one or more woven layers may comprise a material that is durable and therefore protective: for instance, the material may be resistant with regards to physical impacts and collisions, and/or abrasions or impacts with sharp objects. In some configurations, the material may have insulative properties, for example the material may be thermal insulators.

[0113] Where the woven layer is not porous, it may be punched or perforated to provide vapour permeability through it.

[0114] The pliable insulation sheet 10 may be manufactured by layering together the various constituent layers or units to form the panel. Where layers or units are joined together non- adhesively, such as by being fused together, those layers may first be joined together then assembled together with the remaining layers. In some configurations, the permeable adhesive 13 may be provided between each layer or unit which are not already joined together, and the adhesive is allowed to set.

[0115] According to some configurations, subassemblies of layers may be bonded together with an adhesive, either a permeable adhesive or a non-permeable adhesive, then the subassembly may be perforated. Where a permeable adhesive is used on subassemblies, this perforation may be used to increase the overall permeability of the resulting sheet. Or, where the adhesive used is non-permeable, perforation may be used to ensure that there are vapour pathways through the whole of the resulting sheet.

[0116] In some configurations given layers of the insulation sheet may be bonded together by an extruded polymer. The extruded polymer may adhere layers of the sheet together through thermo-bonding. For example, the extruded polymer may be provided between two adjacent layers of the sheet and heated to formally bond the two adjacent layers together.

[0117] The extruded polymer may be for example extruded polyethylene.

[0118] In configurations where the extruded polymer is not porous and/or vapour permeable, the extruded polymer is punched or perforated to provide vapour permeability through it, and to increase the overall permeability of the resulting sheet.

[0119] In some configurations the mass per unit area of a layer of extruded polymer provided between two adjacent layers may be about 5 to about 200 g/m ² .

[0120] Figure 5 illustrates an exploded view of another embodiment of the pliable insulation sheet 10. The pliable insulation sheet 10 of Figure 5 has the layers of the sheet 10 of Figures 4A and 4B, but with the addition of a foil layer 17, a woven polymer layer 18, and a layer of extruded polyethylene 19.

[0121] As shown in Figure 5, the foil layer 17 is joined to a second side of the woven polymer layer 18 by a layer of adhesive 13a. As further shown in Figure 5, a first side of the woven polymer layer 18 is bonded to the insulating layer 11. In some configurations, such as that shown in Figure 5, the woven polymer layer 18 is bonded to the insulating layer 11 by a layer of perforated extruded polymer 19; in other configurations these layers may be bonded together by an adhesive. [0122] The foil layer 17 and woven polymer layer 18 of the embodiment of Figure 5 are not porous. In order to provide vapour permeability through the sheet 10, these layers are to be perforated. The layers may be perforated individually, and any adhesively bonded layers joined by an adhesive. Alternatively, as illustrated in Figure 5, the layers to be perforated may be assembled together and glued as appropriate, with either a vapour permeable or non-vapour-permeable adhesive, and then perforated as one unit.

[0123] As previously described, a permeable unit 14 may include one or two reinforcing layers.

[0124] An example of a sheet with a one-side reinforced permeable unit 14 is illustrated in Figure 6. The sheet 10 of Figure 6 has a core insulating layer 11. A first permeable unit 14a and second permeable unit 14b are adhesively secured to either side of the insulating layer 11 by a permeable adhesive 13a and 13b.

[0125] The first permeable unit 14a comprises a non-perforated and permeable layer 12, interposed between two reinforcing layers 15 and 16, as previously described in relation to Figure 3A.

[0126] The second permeable unit 14b, instead of having a reinforcing layer on each side of the non-perforated and permeable layer 12, only has one reinforcing layer 15 provided on the internal side of the permeable layer 12.

[0127] Such a configuration may provide added permeability, as the entire face of the permeable layer 12 is exposed to the outside of the panel. This configuration may be utilised where the additional durability of a reinforcing layer is not required.

[0128] While illustrated in Figure 6 as being located on the inside of the permeable layer 12, in some configurations a permeable unit with only one reinforcing layer may have the reinforcing layer 15 located towards the outside of the sheet.

[0129] Figure 7 illustrates another embodiment of a pliable insulation sheet 10. The sheet has a foil layer 17 which is bonded to a second side of an insulating layer 11 by an adhesive layer 13a. As shown in Figure 7, the foil layer 17, adhesive layer 13a, and insulating layer 11 are all perforated as a unit; in some configurations the foil layer 17, adhesive layer 13a and insulating layer 11 may each be perforated individually.

[0130] To these layers is bonded a permeable unit 14 by another adhesive layer 13b. Specifically, a first side of the insulating layer 11 is bonded to either of the reinforcing layers 15 or 16 of the permeable unit 14. The adhesive layer 13b is of the permeable adhesive and is not perforated.

[0131] Figure 8 illustrates another embodiment of a pliable insulation sheet 10. In this configuration, an insulating layer 11 defines one of the external surfaces of the sheet 10. The insulating layer 11 is bonded to a second side of a foil layer 17, which is provided within the core of the sheet 10. The insulating layer 11 and the foil layer 17 are bonded by a layer of adhesive 13a. The bonded insulating layer 11 , foil layer 17, and layer of adhesive 13a are then perforated together, and bonded to a permeable unit 14 by a layer of the permeable adhesive 13b which is not perforated. Specifically, the first side of the foil layer 17 is bonded to either of the reinforcing layers 15 or 16 of the permeable unit 14.

[0132] Figure 9 illustrates a further embodiment of a pliable insulation sheet. In this configuration, a perforated woven polymer layer 18 defines one of the external surfaces of the sheet 10. The perforated woven polymer 18 is bonded by a first layer of permeable adhesive 13a to a second side of the insulating layer 11 . The first side of the insulating layer 11 is bonded to either reinforcing layer 15 or 16 of the permeable unit 14 by a second layer of permeable adhesive 13b. Both of the first and second layers of adhesive 13a and 13b are not perforated.

[0133] In some embodiments, a permeable unit 14 according to the disclosure may be combined with one or more layers of fibrous insulation material.

[0134] The fibrous insulation may be of any commonly available fibrous insulation material, such as glass wool made from glass fibres, or polyester wool made from polyester fibres.

[0135] One or each side of a permeable unit 14 may be bonded to a corresponding face of a fibrous insulation panel.

[0136] A fibrous insulation panel may be lapped on both sides by a permeable unit 14. By this configuration, an insulation sheeting may be provided which is resistant to liquid water ingress from both sides of the sheeting, but which allows water vapour to transit through the sheeting in either direction.

[0137] In other configurations a fibrous insulation panel may be attached on one side to a permeable unit 14, and on the other to a punched impermeable layer, such as a reinforcing layer 15, a foil layer 17, or a punched woven polymer layer 18. Such configurations will provide an insulation sheeting which is liquid water impermeable but water vapour permeable at the side of the permeable unit 14, but both liquid water and water vapour permeable at the other side of the insulation sheeting having the punched layer.

[0138] In some embodiments the insulation sheeting may have a permeable unit 14 bonded to one face of a fibrous insulation panel, and the other face of the fibrous insulation panel remains exposed.

[0139] Where another layer, such as the permeable unit 14, is attached to a fibrous insulation layer the two may be joined together using an adhesive.

[0140] In some configurations, the adhesive may be a permeable adhesive. The permeable adhesive may be applied to either or both of the fibrous insulation layer or the layer to which it is to be joined, and the two layers overlaid on each other. Pressure may be applied to ensure the bonding of the two layers to each other by the adhesive. [0141] In other configurations, the adhesive may be a non-permeable adhesive. In order that the vapour permeability of the insulation sheeting is not inhibited, where a non-permeable adhesive is used it may be applied to form a non-continuous layer. For example, a non-permeable adhesive may be applied to only limited parts of the surface of one or each layer.

[0142] This may be achieved by application of the adhesive only to particular spaced apart locations, or in a grid or pattern, such that the layers are bonded together but portions of their respective surfaces do not have glue between them. Vapour will thus still be able to pass through the bonded panels at these locations.

[0143] Where a fibrous insulation panel is to be bonded to another panel as part of an insulation sheeting, a method of selective application of adhesive may include the spraying of the adhesive onto the fibrous insulation panel.

[0144] Because of the fibrous and void-containing nature of the fibrous insulation layer, spraying a limited quantity of adhesive against the face of the layer may provide sufficient adhesive to be deposited onto the layer's surface to allow bonding with another layer, while leaving at least some voids at the panel's surface unfilled by adhesive. If the adhesive is sprayed discontinuously, such as in a coarse mist, some fibres of the layer at its surface may also be left uncoated by the adhesive.

[0145] The areas at the interface of the two layers which remain uncoated with the adhesive will provide areas where water vapour is still able to permeate through the insulation sheeting.

[0146] The adhesive may be applied between the layers in any commonly available manner so as to provide a discontinuous layer of adhesive. Such methods may include coarse spraying of the adhesive, as referred to above, or other methods such as application in spaced strips or any other void-containing pattern.

[0147] The adhesive may be applied in a continuous process, where it is applied continuously onto lengths one or both of the layers which are then brought into contact with each other.

[0148] Where a non-permeable adhesive is used, the permeability of the insulation sheeting will be directly limited by the amount of the surface area of the layer interfaces that are bonded together with the non-permeable adhesive. Accordingly, in at least some preferred forms, a minimum amount of non-permeable adhesive will be applied to the fibrous insulation layer such as will allow the resulting pliable insulation sheeting to be handled and applied to the building structure.

[0149] An embodiment of a pliable insulation sheeting that includes a fibrous insulation layer is shown in Figure 10. As illustrated, the pliable insulation sheeting 10 has a fibrous insulation layer 21, made of for example glass wool or polyester wool, which is joined to a permeable unit 14 by an adhesive 22.

[0150] The adhesive 22 may be either a permeable adhesive or a non-permeable adhesive. As illustrated in Figure 10, the adhesive 22 is a non-permeable adhesive. The adhesive has been applied between the fibrous insulation layer 21 and the permeable unit 14 to form a discontinuous layer, as illustrated in Figure 10. The discontinuous nature of the adhesive layer 22 means that at least some portions of the surface of the permeable unit 14 remain uncovered by the non- permeable adhesive 22. This allows water vapour to permeate through the insulation sheeting 10 at these points.

[0151] While illustrated in Figure 10 as a layer of adhesive 22 interposed between the fibrous insulation layer 21 and the permeable unit 14, the adhesive 22 may in manufacture be applied to only one or to both of the layers.

[0152] In some preferred configurations the adhesive 22 may be sprayed onto the fibrous insulation layer 21. The fibrous insulation layer 21 and permeable unit 14 may then be brought into contact to allow the superficial fibres of the fibrous insulation layer 21 , now partially or wholly coated with the adhesive 22, to contact the permeable unit 14 and bond to it. Because of the fibrous and void-containing nature of the fibrous insulation layer 21 , bonding only the superficial fibres may allow for portions of the permeable unit 14 to be directly exposed to the fibrous insulation layer 21 without any intervening adhesive 22. Where in the foregoing description reference has been made to elements or integers having known equivalents, then such equivalents are included as if they were individually set forth.

[0153] Although embodiments have been described with reference to a number of illustrative embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the preferred embodiments should be considered in a descriptive sense only and not for purposes of limitation, and also the technical scope of the invention is not limited to the embodiments. Furthermore, the present invention is defined not by the detailed description of the invention but by the appended claims, and all differences within the scope will be construed as being comprised in the present disclosure.

[0154] Many modifications will be apparent to those skilled in the art without departing from the scope of the present invention as herein described with reference to the accompanying drawings.