GB2498989A

GB2498989A - Insulation structure suitable for a cavity wall

Info

Publication number: GB2498989A
Application number: GB1201792.7A
Authority: GB
Inventors: Charles William Jack Ayers
Original assignee: Surecav Ltd
Current assignee: Surecav Ltd
Priority date: 2012-02-01
Filing date: 2012-02-01
Publication date: 2013-08-07
Also published as: GB201201792D0

Abstract

The insulation structure 30 comprises an insulation portion 34 with recesses 32 defined thereon. A water permeable sheet 42 overlies the recesses to define a number of voids suitable for receiving and directing water to drain moisture. The recesses may extend in two orthogonal directions which may not be parallel to the edges of the insulation structure. The recesses may be defined by a shaped or profiled sheet provided on a major surface of the insulation structure. Also claimed is an insulation structure 30 which comprises first and second insulation portions 34 and 36 with a spacing structure 38 between the two to define a void 40 operable to receive and direct moisture across the insulation structure. The insulation structure may be configured to interlock with adjacent structures by using co-operative inter engaging formations along its edges. A pair of insulation may be connected together using a corner connector.

Description

CAVITY WALL INSULATION STRUCTURE

• • c •

• • • •

* • •

• I • • #•

FIELD OF THE INVENTION

The present invention relates to cavity wall insulation structures.

5

BACKGROUND

Many modern buildings are now constructed using cavity walls. Cavity walls are generally more effective at improving thermal insulation and inhibiting moisture penetration compared to solid walls. Cavity walls consist of two walls or "leaves" of 10 masonry separated by a cavity or gap. Typically, the walls are around 100 mm thick, separated by a 50 mm gap. The leaves may be constructed from bricks, concrete blocks, hollow clay bricks, timber framing, natural stone or a combination of these materials. The exterior leaf provides the outside of the building, whilst the interior leaf provides the inside of the building. The exterior leaf and the interior leaf are typically 15 tied together at spaced intervals with wall ties spanning the cavity.

To improve the thermal insulation of such cavity walls, it is known to fill the cavity wall with an insulating material. Also, for the cavity wall to work effectively as a moisture barrier, the cavity or gap should not be bridged in any way. Although existing 20 arrangements provide for a cavity wall structure, they each have their own shortcomings.

Accordingly, it is desired to provide an improved cavity wall structure.

25 SUMMARY

According to a first aspect, there is provided a cavity wall insulation structure for placing into a cavity between an inner leaf and an outer leaf of a cavity wall, the cavity wall insulation structure comprising: an insulation structure having recesses thereon; and a water permeable layer overlying the recesses to define a void operable 30 to receive and direct moisture across the cavity wall insulation structure.

The first aspect recognises that a problem with existing cavity wall insulation structures is that water may become trapped between the insulation structure and the inner and/or outer leaves of the cavity wall. Such a situation may occur where the insulation 35 structure abuts closely against the inner and/or outer leaves of the cavity wall, which is likely to occur where the cavity is filled with the cavity wall insulation structure in order to maximise the insulation properties of the cavity wall, such as would occur during "a

1

full filling" of the cavity. Such trapped water can cause damage to the walls and create a health hazard to occupants of the building.

Accordingly, a cavity wall insulation structure is provided. The structure may be 5 configured to be placed into a cavity between an inner leaf and an outer leaf of a cavity wall. The cavity wall insulation structure may comprise an insulation structure having recesses thereon. The cavity wall insulation structure may also comprise a water permeable layer overlying the recesses. The recesses and water permeable layer may together create a void which may receive and may direct any accumulating moisture 10 over the cavity wall insulation structure.

The provision of the void provides a drainage path for any accumulating moisture. Hence, even when the cavity wall insulation structure abuts directly against the inner and/or outer leaves, a drainage path is maintained between the leaf and the cavity 15 wall insulation structure. This helps to prevent the accumulation of any moisture within the cavity by ensuring adequate drainage and helps prevent damage to the walls and the creation of any health hazard. The provision of the water permeable layer enables any moisture to pass from the abutting leaf through the water permeable layer and into the void to facilitate drainage. The provision of the water permeable layer also helps to 20 prevent blockage of the recesses that would otherwise occur during construction by any of the materials (such as mortar) used to construct the leaf. Through this approach, it is possible to provide a cavity wall insulation structure which enables "full fill" of the cavity to maximise the insulation properties whilst also maintaining adequate drainage.

25 In one embodiment, the recesses are shaped onto at least one a major surface of the insulation structure. Accordingly, the recesses may be formed into the insulation structure itself. It will be appreciated that for deformable insulation structures such as, for example, a rigid thermoset phenolic insulation board, such recesses may be pressed into the surface of the insulation structure which will abut against a leaf of the cavity 30 wall using a suitably configured roller. In embodiments, the recesses are shaped onto an outwardly facing major surface of the first and second insulation structures. In this way, drainage is provided where the cavity wall insulation structure abuts both the inner and outer leaves.

35 In one embodiment, the recesses are defined by a shaped sheet provided on a major surface of the insulation structure. Accordingly, the recesses may be formed into a separate sheet which then abuts against the major surface of the insulation structure.

2

In one embodiment, the recesses extend across the major surface of the insulation structure. Extending the recesses over the entire surface of the insulation structure helps to provide a continuous drainage path over the insulation structure.

5 In one embodiment, the recesses extend in two orthogonal directions across the major surface of the insulation structure. By providing recesses which extend orthogonally in different directions across the insulation structure, a drainage path may be maintained irrespective of the orientation of the cavity wall insulation structure within the cavity wall.

10

In one embodiment, the recesses extend in directions which are non-parallel with respect to edges of the insulation structure. Typically, each insulation structure is placed within a cavity and is orientated by and rests on an edge of that insulation structure. By providing recesses which extend in directions which are not parallel to the 15 edges of the insulation structure, a drainage path over the surface of the insulation structure is provided for the flow of moisture under the effects of gravity.

• • •

. In one embodiment, the recesses are positioned to align with recesses of a

••••••

neighbouring insulation structure. Accordingly, moisture will be directed from recesses

.**. J 20 in one insulation structure and into recesses of a neighbouring insulation structure in • • •

order to maintain a substantially continuous drainage path within the cavity wall.

In one embodiment, the water permeable layer comprises a water permeable membrane layer affixed to overlie the recesses. As mentioned above, a water 25 permeable membrane protects the recesses from being blocked whilst still facilitating the transfer of moisture.

In one embodiment, the water permeable layer extends beyond the insulation structure. By providing a water permeable layer which extends beyond the edges of 30 the insulation structure, the water permeable layer may overlap a neighbouring insulation structure in order to prevent any gaps between the neighbouring insulation structures.

In one embodiment, the water permeable layer extends in at least two orthogonal 35 directions beyond edges of the insulation structure. Accordingly, an overlap may be provided in two directions in order to prevent a gap between neighbouring insulation structures. Also, the overlap may be wrapped around an edge of an orthogonally neighbouring insulation structure such as would occur in the corner of a cavity wall.

3

According to a second aspect, there is provided a cavity wall insulation structure for placing in a cavity between an inner leaf and an outer leaf of a cavity wall, the cavity wall insulation structure comprising: a first insulation structure; a second insulation 5 structure; and a spacing structure operable to space the first insulation structure from the second insulation structure to define a void operable to receive and direct moisture across the cavity wall insulation structure.

The second aspect recognises that a problem with existing insulation structures such as, 10 for example, those that fill the cavity of a cavity wall is that any moisture which ingresses into the cavity may not drain from the cavity. In particular, so-called "full filled" cavities may accumulate moisture which is unable to drain from the cavity due to the presence of the insulation structure which fills the cavity.

15 Accordingly, a cavity wall insulation structure may be provided. The structure may be placed in a cavity between an inner and an outer leaf. The cavity wall insulation

; structure may comprise a first insulation structure. The cavity wall insulation structure

• • •

. may also comprise a second insulation structure. The cavity wall insulation structure

••••••

may further comprise a spacing structure which spaces the first insulation structure

. • •. ; 20 away from the second insulation structure to create a gap or void between the two • • •

insulation structures through which moisture which enters the cavity may be drained.

Through this approach, a "full fill" insulation structure is provided which enables moisture accumulating within the cavity to drain. Spacing the two insulation structures apart 25 creates a drainage path along which the moisture may drain. Spacing the two insulation structures apart also creates an air gap which helps the insulation properties of the cavity. Accordingly, a structure is provided which both improves the insulation properties of the cavity wall and prevents the accumulation of any moisture within the cavity.

30

In one embodiment, the spacing structure comprises a plurality of spacers which retain opposing surfaces of the first insulation structure and the second insulating structure. Accordingly, a number of spacers are provided which couple opposing surfaces of the first and second insulating structures.

35

In one embodiment, the spacers comprise a fixing structure operable to fix the spacers to the first and second insulation structure. Accordingly, fixings may be provided which fix the spacers to the first and second insulation structures, thereby fixing the first

insulation structure to the second insulation structure to create a single structure which can be easily handled.

In one embodiment, the spacers extend across a major surface of the first and second 5 insulation structures.

In one embodiment, the spacers are elongate.

In one embodiment, the spacers define at least one void extending between major 10 opposing surfaces. Hence, multiple voids are created between the first and second insulation structures, each of which provides drainage.

In one embodiment, the spacers define an internal conduit extending therealong. Providing an internal conduit adds a further drainage path.

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*

In one embodiment, each spacer defines at least one opening extending between

.. . opposing major surfaces of the spacer. Providing openings or vents between the

• • •

elongate surfaces of the spacer facilitates air flow between the voids defined by

••••••

• * neighbouring spacers in order to reduce any pressure differential within each void.

• • • 20 • • •

• • •

In one embodiment, the spacers are operable to hold the first insulation structure parallel to the second insulation structure. Accordingly, the resultant structure provides ; two parallel major surfaces which may each abut against a leaf of the cavity wall.

25 In one embodiment, said spacer comprises a sheet structure having voids extending therein. Accordingly, a separate sheet may be provided which has voids extending therethrough or thereacross which acts as a drainage spacer.

In one embodiment, said sheet structure has recesses are shaped onto at least one a 30 major surface of said sheet structure to define said voids. The recesses may be formed onto the surface or formed by the surface in order to provide the voids within which water may flow.

In one embodiment, said sheet structure comprises a sheet overlying said at least one a 35 major surface of said sheet structure to define said voids. Hence, the spacer may be a composite structure formed of more than one sheet. One or more of those sheets may be insulating in order to improve the insulation properties of the spacer.

5

In one embodiment, the cavity wall insulation structures comprise an interlocking structure operable to interlock with a neighbouring insulation structure.

In one embodiment, the interlocking structure comprises a depth restrictor plate having 5 insulation structure engaging pins upstanding from opposing surfaces thereof. Such an arrangement provides for effective fixing between neighbouring insulation structures since the pins may be received within the insulation structures and fix the two structures together.

10 In one embodiment, the insulation structure defines the interlocking structure.

Accordingly, rather than having separate interlocking structures, the insulation structure may itself define the interlocking structure between the insulation structures.

In one embodiment, the interlocking structure comprises mating structure along at least 15 one edge of the insulation structure and a complimentary mating structure along a parallel edge of the insulation structure.

In one embodiment, the interlocking structure comprises a mating structure along two • orthogonal edges of the insulation structure and a complimentary mating structure

• . 20 along two parallel edges of the insulation structure.

• •

In one embodiment, the interlocking structure and the complimentary mating structure

• • i each comprise one of a recess and a protrusion.

• ••

25 In one embodiment, the insulation structure defines apertures shaped to receive wall ties extending between the inner and outer leaves. Accordingly, apertures may be provided through which the wall ties may pass. Alternatively, it will be appreciated that the insulation structure may be pressed on to the wall ties which may then deform the insulation structure when being mated together.

30

In one embodiment, the cavity wall insulation structures comprise comprising a corner coupling operable to couple orthogonally abutting neighbouring insulation structures. Accordingly, a coupling may be provided which couples neighbouring insulation structures at a corner of the cavity wall.

35

In one embodiment, the insulation structure is dimensioned to fill the cavity by extending between the inner leaf and the outer leaf.

6

• • • •

4 • • • ♦

In one embodiment, the major surface of the insulation structure is generally rectangular.

Further particular and preferred aspects of the present invention are set out in the 5 accompanying independent and dependent claims. Features of the dependent claims may be combined with features of the independent claims as appropriate, and in combinations other than those explicitly set out in the claims.

Where an apparatus feature is described as being operable to provide a function, it will 10 be appreciated that this includes an apparatus feature which provides that function or which is adapted or configured to provide that function.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described further, by way of example only, with reference 15 to preferred embodiments thereof as illustrated in the accompanying drawings, in which:

Figure 1 shows a cavity wall insulation structure according to one embodiment incorporated into a cavity of a cavity wall of a building;

Figures 2a to 2c and Figure 3 show the cavity wall insulation structure of Figure 1 in more 20 detail;

Figures 4a to 4c, 5a, 5b and 6 illustrate a corner connector for connecting two neighbouring cavity wall insulation structures at a corner of a cavity wall;

Figures 7a to 7c and 8 illustrate a cavity wall insulation structure according to one embodiment;

25 Figures 9a to 9c show a cavity wall insulation structure according to one embodiment; and

Figures 10a to lOd and 11 show a cavity wall insulation structure according to one embodiment.

30 DESCRIPTION OF THE EMBODIMENTS Overview

Before discussing embodiments in any more detail, first an overview will be provided. Embodiments relate to a full fill cavity wall insulation structure which provides enhanced thermal and moisture drainage properties. The cavity wall insulation structure fits 35 between the inner and outer leaves of a cavity wall.

Recesses are provided on the surface of the cavity wall insulation structure. The presence of the recesses ensures that any moisture that ingresses, for example,

7

between the cavity wall insulation structure and the leaves of the cavity wall can track along the cavity wall insulation structure and eventually drain out at the bottom of the cavity wall. The recesses are protected from becoming blocked through the presence of an overlying water permeable membrane.

5

In addition, the cavity wall insulation structure is composed of a plurality of insulation structures each of which is typically impermeable. Each of the plurality of insulation structures are spaced apart by spacers to define further drainage channels between the insulation structures themselves. This arrangement further assists in the drainage of 10 any moisture from within the cavity, whilst the presence of air gaps between the insulation structures also assists in the insulation properties of the cavity wall insulation structure.

Installed Cavity Wall Insulation Structure 15 Figure 1 shows a cavity wall insulation structure, generally 30, incorporated into a cavity 17 of a cavity wall 18 of a building. In this example, only one sheet of the cavity wall

.. . insulation structure 30 is shown. Further sheets (not shown) may be stacked above and

• • •

* ** below this sheet to provide insulation throughout the cavity 17.

• • • • • • • • •

• •

fc •

20 The cavity wall 18 has an exterior wall 18 and an interior wall 20. In this example, the exterior and interior walls 19, 20 are constructed from bricks, although they may also be constructed from concrete blocks, hollow clay bricks, timber framing or natural stone. The cavity wall insulation structure is located in the cavity 17 of the cavity wall 18.

25 As will be explained in more detail below, the cavity wall insulation structure 30

comprises a first insulation structure 34 separated from a second insulation structure 36 by spacers 38. The first insulation structure 34 and second insulation structure 36 each comprise rectangular panels of an insulating material such as, for example, a rigid thermoset phenolic insulation board which may be covered on one or more surfaces 30 by metallic foil. Such insulating structures are water impermeable. The spacers 38 create a gap or void 40 between the first insulation structure 34 and the second insulation structure 36. The first insulation structure 34 is provided with recesses 32 on an outward facing surface 42 which typically abuts against an inward facing surface 44 of the outer leaf 19. The presence of the void 40 and the recesses 32 facilitate the 35 drainage of any moisture which enters the cavity 17. In order to protect the recesses 32 from becoming blocked, a water permeable membrane 46 is provided which overlies the surface 42. Water droplets will traverse the cavity wall insulation structure 30 and

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will gather on the ground surface of the cavity 17 in the vicinity of weep holes in the exterior wall 19.

Cavity Wall Insulation Structure - Example 1 5 Figures 2a to 2c and Figure 3 show the cavity wall insulation structure 30 of Figure 1 in more detail. The cavity wall insulation structure 30 will typically have dimensions of 1200 mm x 450 mm.

In this example, six spacers 38 are provided. It will be appreciated that more or fewer 10 than this number of spacers 38 may be provided. Each spacer 38 comprises an elongate rectangular extrusion. An internal void 37 may be provided along the elongate axis of each spacer 38 to provide an additional drainage path within each spacer 38. In addition, a number of vent holes 48 are provided along the elongate axis of each spacer 38. The provision of such vent holes 48 helps to equalise the air pressure 15 within the voids 39 created by the spacers 38 and the first and second insulation structures 34, 36. The spacers 38 in this embodiment are glued onto the surface of the insulation structures 34,36. However, it will be appreciated that it would be possible to provide for protrusions on the spacers 38 which engage with and deform the insulation • structures 34,36 to hold these in place. Accordingly, the first and second insulation

, 20 structures 34, 36 are separated by vertical spacers 38 with perforated sides to allow air pressure equalisation and form mini cavities which also act as a moisture barrier.

• • • • • • • ••

• • • •

The recesses 32 are formed on the external surface 42 of the first insulation structure 34. The recesses 32 are typically pressed into the external surface 42 by a roller. In this 25 example, the recesses define a generally square lattice, with each recess being set at an angle of 45° to the edges of the first insulation structure 34. Setting the recesses in this way helps to assist in the drainage of moisture across the surface 42 of the first insulation structure 34. The recesses 32 may be of generally triangular, quadrilateral or circular cross sections. Although recesses 32 are shown on the outward facing surface 30 42 of the first insulation structure 34, it will be appreciated that similar recesses 42 may also be formed on an outward facing surface of the second insulation structure 36 to assist drainage at the contact between the cavity wall insulation structure 30 and the inner leaf 20.

35 Overlying the surface 42 is a water permeable sheet 46. The presence of the water permeable sheet 46 helps prevent the recesses 32 from becoming blocked during construction of the cavity wall 18. Typically, the water permeable membrane 46 is a

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micro-porous membrane. As can be seen, an overlap tail 47 is provided which overlaps with a neighbouring cavity wall insulation structure 30 within the cavity wall 18.

Corner Connector

5 Figures 4a to 4c, 5a, 5b and 6 illustrate a corner connector 60 for connecting two neighbouring cavity wall insulation structures 30 at a corner of a cavity wall 18. The corner connector 60 comprises a planar L shaped sheet 100 dimensioned to cover a corner of two abutting cavity wall insulation structures 30. Upstanding ribs 100 extend out of the planar L shaped sheet 100 to define a recess into which the two abutting 10 cavity wall insulation structures 30 sit. The upstanding ribs 100 extend from both major surfaces of the planar L shaped sheet 100 to retain two pairs of two abutting cavity wall insulation structures 30, one pair above the other within the corner of the cavity wall 18.

Typically, abutting edges 70 of the neighbouring cavity wall insulation structures 30 are 15 mitred to provide for a continuous cavity 39. Also, the water permeable membrane 46 may be provided with an additional tail extending past the edge 70 which may be wrapped around the corner and retained in place by the connector plate 60. It will be appreciated that two connector plates will typically be used, one at an upper surface of the cavity wall insulation structures 30 and one at a lower surface.

20

Cavity Wall Insulation Structure - Example 2

Figures 7a to 7c and 8 illustrate a cavity wall insulation structure 30a according to one embodiment. This embodiment is made of similar materials having similar dimensions and properties to the embodiments mentioned above. The edges of the first and 25 second insulation structures, 34a and 36a, are routed in order to provide recesses and protrusions to facilitate the interlocking of neighbouring cavity wall insulation structures 30a. Also, rather than having box section spacers, the spacers 38a have an l-section. Again, the spacers 38a are provided with vent holes 48a.

30 Cavity Wall Insulation Structure - Example 3

Figures 9a to 9c show a cavity wall insulation structure 30b according to one embodiment. This embodiment is made of similar materials having similar dimensions and properties to the embodiments mentioned above. In this embodiment, the recesses 32b are defined by a series of elongate quadrilaterals having circular minor 35 sides. Overlaying the recesses 32b is provided a water permeable membrane 46b. The first insulation structure 34b and the second insulation structure 36b are coupled using spacers 38 shown in Figure 2a. In order to facilitate interlocking of neighbouring cavity

10

wall insulation structures 30b, the first insulation structure 34b and the second insulation structure 36b are connected with an offset in two orthogonal directions x and y.

Cavity Wall Insulation Structure - Example 4 5 Figures 10a to lOd and 11 show a cavity wall insulation structure 30c according to one embodiment. This embodiment is made of similar materials having similar dimensions and properties to the embodiments mentioned above. In this embodiment, recesses 32c are defined by a series of elongate quadrilaterals having circular minor sides. The recesses 32b are formed on a separate sheet 130 onto which a water permeable 10 membrane 46c is attached. The water permeable membrane 46c is typically a micro porous membrane and is provided with an overlap tail 47c which overlaps with a neighbouring cavity wall insulation structure 30c within the cavity wall 18.

A first insulating structure 34c and a second insulating structure 36c are provided. In 15 order to facilitate interlocking of neighbouring cavity wall insulation structures 30c, the first insulation structure 34c and the second insulation structure 36c are provided with locating tongues 140 which engage with locating grooves 150.

The separate sheet 130 is placed against the first insulating structure 34c and may be 20 affixed to the first insulating structure 34c typically using an adhesive.

Sandwiched between the first insulation structure 34c and the second insulation structure 36c is an insulating spacer 38c. The insulating spacer 38c is a sheet of silver foil-enclosed air pockets which form a, typically 10 mm, insulated drainage channel 25 between the sheets of silver foil 170. The air pocket structure 160 is typically formed by a pair of shaped sheets in a similar manner to bubble wrap. This air pocket structure 160 is then sandwiched between two silver foil sheets 170. Alternatively, one of the silver foil sheets 170 may be used to form the air pocket structure 160. Again, the spacer 38c may be affixed to the first insulation structure 34c and the second insulation 30 structure 36c using an adhesive.

Although illustrative embodiments of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is understood that the invention is not limited to the precise embodiment and that various changes and modifications can be 35 effected therein by one skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents.

11

Claims

1. A cavity wall insulation structure for placing into a cavity between an inner leaf and an outer leaf of a cavity wall, said cavity wall insulation structure comprising: 5 an insulation structure having recesses thereon; and a water permeable layer overlying said recesses to define a void operable to receive and direct moisture across said cavity wall insulation structure.

2. The cavity wall insulation structure of claim 1, wherein said recesses are shaped 10 onto at least one a major surface of said insulation structure.

3. The cavity wall insulation structure of claim 1 or 2, wherein said recesses extend across said major surface of said insulation structure.

15 4. The cavity wall insulation structure of any preceding claim, wherein said recesses extend in two orthogonal directions across said major surface of said insulation structure.

, * *. I 5. The cavity wall insulation structure of claim 1, wherein said recesses are defined

• ••

; 20 by a shaped sheet provided on a major surface of said insulation structure.

• •

• * * • • 6. The cavity wall insulation structure of any preceding claim, wherein said recesses extend in directions which are non-parallel with respect to edges of said insulation structure.

25

7. The cavity wall insulation structure of any preceding claim, wherein said recesses are positioned to align with recesses of a neighbouring insulation structure.

8. The cavity wall insulation structure of any preceding claim, wherein said water 30 permeable layer comprises a water permeable membrane layer affixed to overlie said recesses.

9. The cavity wall insulation structure of any preceding claim, wherein said water permeable layer extends beyond said insulation structure.

10. The cavity wall insulation structure of any preceding claim, wherein said water permeable layer extends in at least two orthogonal directions beyond edges of said insulation structure.

12

11. A cavity wall insulation structure for placing in a cavity between an inner leaf and an outer leaf of a cavity wall, said cavity wall insulation structure comprising: a first insulation structure;

5 a second insulation structure; and a spacing structure operable to space the first insulation structure from said second insulation structure to define a void operable to receive and direct moisture across said cavity wall insulation structure.

10 12. The cavity wall insulation structure of claim 11, wherein said spacing structure comprises a plurality of spacers which retain opposing surfaces of said first insulation structure and said second insulating structure.

13. The cavity wall insulation structure of claim 12, wherein said spacers comprise a 15 fixing structure operable to fix said spacers to said first and second insulation structure.

14. The cavity wall insulation structure of claim 12 or 13, wherein said spacers extend across a major surface of said first and second insulation structures.

j 20 15. The cavity wall insulation structure of any one of claims 12 to 14, wherein said spacers are elongate.

16. The cavity wall insulation structure of any one of claims 12 to 15, wherein said spacers define at least one void extending between major opposing surfaces.

• • •

• ♦ • 25

• • • z-v"'

17. The cavity wall insulation structure of any one of claims 12 to 16, wherein said spacers define an internal conduit extending therealong.

18. The cavity wall insulation structure of any one of claims 12 to 17, wherein each 30 spacer defines at least one opening extending between opposing major surfaces of said spacer.

19. The cavity wall insulation structure of any one of claims 12 to 16, wherein said spacers are operable to hold said first insulation structure parallel to said second

35 insulation structure.

20. The cavity wall insulation structure of claim 12, wherein said spacer comprises a sheet structure having voids extending therein.

13

21. The cavity wall insulation structure of claim 20, wherein said sheet structure has recesses are shaped onto at least one a major surface of said sheet structure to define said voids.

22. The cavity wall insulation structure of claim 20, wherein said sheet structure comprises a sheet overlying said at least one a major surface of said sheet structure to define said voids.

10 23. The cavity wall insulation structure of any preceding claim, comprising an interlocking structure operable to interlock with a neighbouring insulation structure.

24. The cavity wall insulation structure of claim 23, wherein said interlocking structure comprises a depth restrictor plate having insulation structure engaging pins upstanding

15 from opposing surfaces thereof.

25. The cavity wall insulation structure of claim 23, wherein said insulation structure defines said interlocking structure.

; 20 26. The cavity wall insulation structure of claim 25, wherein said interlocking structure comprises mating structure along at least one edge of said insulation structure and a ; complimentary mating structure along a parallel edge of said insulation structure.

27. The cavity wall insulation structure of claims 25 or 26, wherein said interlocking

• • •

. '.I 25 structure comprises a mating structure along two orthogonal edges of said insulation structure and a complimentary mating structure along two parallel edges of said insulation structure.

28. The cavity wall insulation structure of any one of claims 25 to 27, wherein said 30 interlocking structure and said complimentary mating structure each comprise one of a recess and a protrusion.

29. The cavity wall insulation structure of any preceding claim, wherein said insulation structure defines apertures shaped to receive wall ties extending between 35 said inner and outer leaves.

30. The cavity wall insulation structure of any preceding claim, comprising a corner coupling operable to couple orthogonally abutting neighbouring insulation structures.

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31. The cavity wall insulation structure of any preceding claim, wherein said insulation structure is dimensioned to fill said cavity by extending between said inner leaf and said outer leaf.

32. The cavity wall insulation structure of any preceding claim, wherein said major surface of said insulation structure is generally rectangular.

33. A cavity wall structure as hereinbefore described with reference to the accompanying drawings.

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