FIELD OF THE INVENTION

The present invention relates to systems and methods for the thermal insulation of building structures. In particular, the invention relates to a cassette system for installation in modular units into/onto existing buildings or storage structures, such as large scale tanks or buildings, and related methods of installation of such modular thermal/acoustic insulation systems.

BACKGROUND TO THE INVENTION

There are a variety of reasons for which a large storage tank or building may require thermal or acoustic insulation. Old insulation may require replacement, or a change of purpose may require newly installed thermal or acoustic insulation where insulation may not have previously been required for a tank or structure's previous purpose. A variety of existing methods are available for installing such insulation systems to the external walls of a building/storage tank.

Most existing methods either require complex and expensive equipment, or significant manpower in order to install the insulation and associated retaining or cladding systems.

One such known method is the use of a scaffold erected around the structure to enable manual access to all areas of the walls which need insulation applying. Such scaffold has to be erected to the full height and around the full perimeter needing insulation.

Traditional methods of thermal insulation of large structures typically use, firstly, mechanical fastening systems to hold the insulation materials in place on the external walls/body of the structure. Secondly, an outer cladding system is held in place by further mechanical fixing systems to hold the protective cladding in place and provide further protection from either impact, water or dirt ingress etc. A series of steps would typically see insulation material applied in rigid slab form (typically 0.6m x 0.9m) built up in rings or rows around the walls of the structure and held in place using anchors, pins, insulation support rings, circumferential tie bands and the like, placed at regular (e.g. 0.3m to 0.5m) intervals, or combinations of the above.

On completion of the installation of the insulation material, cladding systems, typically metal cladding systems, such as flat or profiled aluminium or coated corrugated steel sheets, would be secured in place using a combination of pop rivets or self-tapping screws at regular intervals up vertical seams, and 4cm wide stainless steel bands incorporating breather clips to accommodate expansion.

In some cases top hat securing units hammered over ribbed pin heads that are pre welded or adhered to the wall of the structure or tank would be utilised to further secure the cladding over the insulation material. The above approaches, although effective at achieving the required insulation's conservation of energy/heat loss objectives, are extremely labour intensive in their application and involve a significant amount of time and effort in the erection and removal of scaffolds and application of the insulation system, this in turn results in many man-hours being required on site for each installation.

There is therefore a need for improved insulation systems for insulating walls of buildings or structures.

SUMMARY OF THE INVENTION

The present invention seeks to provide an alternative to the known methods used and in so doing provides a system for insulation of a wall, comprising a plurality insulation cassettes, each cassette comprising: a shell having a major wall and an insulation cavity defined within the shell by at least the major wall of the shell and a plurality of minor walls of the shell extending substantially perpendicularly from the major wall; a plurality of lateral sides disposed at edges of the major wall, the lateral sides having complementary interlocking features formed in the shell which are configured to interlock to retain the cassettes adjacent one another when interlocked, to form a substantially continuous interlocked modular insulation system over the wall to be insulated.

The interlocking insulation cassettes, preferably being generally connected to an elongate member such as a rope, bar, strap or shock-cord extending across a surface of the wall to be insulated, allow the full insulation system to be installed in a single operation. This is more efficient than previous known methods in which insulation was first installed, and then cladding sheets separately secured in place over the top of the insulation. The overall result is a reduction in the man hours and materials and tooling required for installation of insulation of a wall of the structure. A rope, strap or shock- cord extending across a wall to be insulated includes a rope extending across or close to a surface of a substantially planar wall, as well as around a surface of a substantially cylindrical wall. The rope, strap or shock-cord may extend across an internal or external surface of a wall comprised in an enclosure. The system and methods described herein can therefore be adapted to provide insulation to an internal surface or to an external surface of a wall of an enclosed structure. For practical reasons, it is envisaged that particularly beneficial uses will be for insulating the outside of walled structures, such as storage tanks. The cassettes may be assembled together into a modular structure, comprising a plurality of cassettes. Each cassette may be considered a module or a sub-module of a modular system. The invention can be used for thermal and/or acoustic insulation.

The disclosed system and methods offer an 'all-in-one' approach incorporating the insulation and protective cladding in one cassette. Once a number of cassettes have been joined together they form a modular system. This system can encase the item it surrounds The system can primarily stand-off from, i.e. be held away from the surface of the item it surrounds.

The disclosed system and methods enable the insulation of large structures without a need for scaffolding, it is intended that cassettes are normally installed using rope- access personnel. The system saves on labour costs due to the skill element of installation being lower than conventional systems, and the cassettes will be pre fabricated and pre-insulated at ground level in a workshop. It also enables the insulation of flat and/or curved surfaces due to its innate particulars.

Further optional features of the modular system and its cassettes are described in the following.

The complementary interlocking features are preferably configured to engage when translated substantially parallel to the major wall of the shell.

Each cassette may further comprise an attachment portion configured for connection to a rope, strap, bar, tube, shock-cord or other elongate member extending across or around a surface the wall or other item to be insulated, such that, when installed, the system comprises an array of interlocking insulation cassettes retained to the wall by an elongate member such as a rope, strap, bar, tube, shock-cord, extending across a surface of the wall and located between the cassettes and the wall. The elongate member, such as a rope, strap, bar, tube or shock-cord provides a single connection mechanism to which each insulation cassette can be connected in a single operation. This results in reduced requirement for tooling and complex manipulation of heavy materials.

Ropes are described in the following and in some of the specific examples. However, that term should not be considered to be limiting to a rope in particular. Other suitable means would include straps, bars, tubes, bungee cords, shock cords, elastic or inelastic elongate items, or any other elongate rope or strap-like member. In some examples, any of these can be attached to the surface of the wall at discreet intervals in a similar manner to a rope. The rope or other elongate rope or strap-like member is optionally attached at discreet spaced intervals along its length such that a tie can be attached around the rope and through a part of the body of the insulation cassette to fix the cassette against the wall. However, in certain implementations, especially those in which the elongate member, such as a rope or shock cord(s) extend(s) around the structure to be insulated, the rope may not need to be affixed at intervals and mere tension in the elongate member such as a rope or shock cord may hold it in place sufficiently to enable cassettes to be assembled on to the ropes.

The term rope in the present specification can be replaced by the examples discussed above and so can alternatively comprise a rope, strap, shock- or bungee-cord (elastic) or inelastic cords, a bar or any other elongate rope or strap-like member extending across a wall to achieve the function required of the rope as described in this specification.

The invention further provides a method of insulating a wall of an item or structure, comprising the steps of: providing a plurality of insulation cassettes comprising a shell having a major wall and an insulation cavity defined within the shell by at least the major wall of the shell and a plurality of minor walls of the shell extending substantially perpendicularly from the major wall, the cassettes having a plurality of lateral sides disposed at edges of the major wall, the lateral sides having complementary interlocking features formed in the shell which are configured to interlock to retain the cassettes adjacent to one another when interlocked, thus forming a continuous interlocked modular insulation system over the wall to be insulated; installing the cassettes against the wall and interlocking adjacent lateral sides of adjacent cassettes to form a continuous interlocked modular insulation system over the wall to be insulated.

The method enabled by the invention includes all the advantages described above for the system. As will be evident, the method and/or the system can include any of the same or similar features described in relation to each.

The method may further comprise the steps of: attaching at least one elongate member to or around the wall to be insulated, optionally at a plurality of points, to extend across or around the wall of the structure; attaching adjacent cassettes to the at least one elongate member such as a rope, strap, bar, tube or shock-cord, such that the at least one rope, or shock-cord is located between the modules and the wall and acts to retain the cassettes to or against the wall.

The insulation cassettes may further comprise an attachment portion, configured for attachment to the elongate member, such as a rope, bar, tube strap or shock-cord on the surface of the wall, to retain the cassettes in place with the elongate member located between the modules and the wall.

The rope attachment portion may comprise a plurality of attachment regions located at different lateral positions relative to a wall of the shell, each attachment region configured for connection to an elongate member such as a rope, strap, bar, tube or shock-cord on the wall to be insulated, and the method preferably includes selecting one or more attachment regions on each insulation cassette and attaching the selected attachment region to the rope, strap or shock-cord.

The provision of a plurality of attachment regions located at different lateral positions relative to the wall or shell enables the installation team to quickly and easily attach the rope, strap or shock-cord to the suitable portion of the insulation cassette without a need for precise installation of the elongate member such, as a rope, strap, bar, tube or shock-cord, on the wall at a corresponding location in the preparation phase where the rope, strap or shock-cord is being installed on the wall prior to installation of the insulation cassettes. The shell of the insulation cassettes may comprise lips and/or grooves configured to engage with corresponding lips and/or grooves on adjacent insulation cassettes; and wherein the method further comprises engaging lips of the insulation cassettes in grooves of adjacent cassettes. The provision of corresponding lips and grooves, in a "tongue and groove" configuration, allows the insulation cassettes to be quickly and easily slotted into one another when installing the modules. This combined with a straight forward attachment to the rope on the wall facilitates a quick and efficient installation of the system.

The shell of the insulation cassette may be bent or curved during installation to conform to the shape of the wall to be insulated. This is advantageous when insulating irregular, or curved, walls. This is particularly convenient when insulating, for example, substantially cylindrical storage tanks or large diameter piping.

Adjacent insulation cassettes may be sealed to one another at their joints. This can create a sealed or hermetic insulation system extending over the wall to be insulated, which prevents air, dust, liquid or gas ingress into the insulation modules, which could reduce the performance of the insulation material provided in the cavity.

Insulation material such as: fibre materials, rock and slag wool, cellulose, or natural fibres or any other known form of insulation material may be provided in the cavity. However, implementations could be envisaged where the mere air gap provided in the cavity also provides an insulating function.

An insulation cassette is also provided for application to the wall of a structure to provide insulation to the wall, the cassette comprising: a shell having a major wall and an insulation cavity defined within the shell by at least the major wall of the shell and a plurality of minor walls of the shell extending substantially perpendicularly from the major wall; a plurality of lateral sides disposed at edges of the major wall, the lateral sides having complementary interlocking features formed in the shell which are configured to interlock to retain the cassettes adjacent to one another when interlocked, to form a continuous interlocked modular insulation system over the wall to be insulated.

The system and method of the invention can also comprise any or all features of the module described above and in the following. The shell of the insulation cassette may comprise a compliant region which enables the shell to be bent in its major plane to conform to the shape of the wall to be insulated. This may further be provided in the minor walls of the module to allow the minor walls to continue to provide a substantially enclosed envelope for the insulation cavity whilst still allowing the cassette as a whole to be bent in its major plane. The compliant region may comprise embossed, kinked, folded or fanned portion to enable regions of the cassette to expand or compress in the plane of the respective region or wall section, to permit the bending of the cassette.

In certain embodiments, the compliant region is located across the width of a first minor wall of the plurality of minor walls and across the width of a second minor wall of the plurality of minor walls which is opposite the first minor wall. In certain embodiments, the compliant region in each of the first minor wall and second minor wall consists of a plurality of cut out sections that form a plurality of fingers.

The cassette or cassettes may be configured to provide an overlapping portion of the insulation cavity on each corresponding lateral side of the cassette. A first may extend adjacent the wall to be insulated when installed, while the opposing lateral side of the insulation module may be configured to provide the corresponding overlapping portion of the insulation cavity which extends adjacent the major wall of the shell. In this manner, when the cassettes are engaged, overlapping portions of the insulation cavities are provided. This eliminates a direct heat path at joins within the insulation modular system.

Similarly, a corresponding overlapping arrangement may be provided at third or fourth lateral sides or at the tops and/or bottoms of the insulation cassettes, so that, for example, a top edge of a first cassette provides an overlap with the corresponding bottom edge of a neighbouring cassette provided above the first cassette.

Where insulation material is provided, it may extend into the overlapping portions such that overlapping insulation material is provided in the overlapping portions of the insulation cavity. In certain embodiments, a plurality of studs are mounted on the insulation material which project out of the insulation material, in use, towards the wall, to ensure spacing between the insulation material and the wall. Such an arrangement can mitigate CUI (corrosion under insulation) as the insulation does not come into contact with the insulated surface. A channel may be provided along a side, top or bottom of the module for receiving the corresponding overlapping portion of the insulation cavity defined on the corresponding portion of the neighbouring insulation cassette. This channel may be defined on one part by a step provided along a minor wall of the insulation cassette and a further wall of the channel may be provided by a lip extending laterally from that minor wall. A corresponding channel may be provided through receiving the lip at the same time that the overlapping portion is received in the channel. Again, a similar arrangement may be provided on top and/or bottom edges of adjacent insulation cassettes.

The modular system, and methods described enable a reduction in labour required and in material/equipment required on site for insulation of a structure, such as scaffold, compressors, vehicles, power tooling.

Furthermore, it is envisioned that this system will be able to be slotted together around a structure, storage vessel such as a tank or large diameter piping system and held in position using elastic ropes such as 'shock cords' or 'bungee' cords on the wall- side of the system, allowing the surface in question to be completely insulated and clad in one operation. Each seam between adjacent cassettes (longitudinal and vertical) of the system can be cold solvent welded/sealed as the installation operation progresses, resulting in a sealed modular system with no possibility of water ingress into the insulation cavities. Fundamentally, the system forms a sealed shell containing the insulation within a modular structure and sealed outer shell.

It is envisioned that this system lends itself to application using rope access, thus doing away with the need for scaffolding and the associated on-site labour time required for the purpose of scaffolding and installing insulation described in relation to prior art methods.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described with reference to the accompanying drawings, in which:

Figure 1 shows a subsection of an installed insulation system according to embodiments of the invention;

Figures 2 to 4 show sequential positions during interlocking of adjacent insulation cassettes side by side; Figures 5 to 7 show sequential steps in installation of further insulation cassettes adjacent to the first insulation cassette;

Figure 8 shows a section through an insulation cassette from a first lateral direction;

Figure 9 shows further detail of the interconnections between adjacent first and second lateral sides of adjacent cassettes;

Figure 10 shows a further illustration of interconnections between third and fourth lateral sides of the insulation cassettes;

Figures 11 to 16 provide simplified schematic diagrams depicting views of a shell and parts of a shell in accordance with certain embodiments of the invention, and Figure 17 provides a simplified schematic diagram depicting a block of insulating material in accordance with certain embodiments of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENT(S)

Figure 1 shows an example of a partially installed system in accordance with an embodiment of the invention. Figure 1 shows a wall (10) to be insulated. The wall (10) is not straight but is illustrated with a slight curvature. This can be the case, for example, for a cylindrical or curved-walled tank.

The system (1) in accordance with an embodiment of the invention has been partially installed against the wall (10). As can be seen, the system comprises a plurality of insulation cassettes (100, 200, 300 and 400) which have been installed in a "tiled" arrangement against the wall (10). Prior to the installation of the cassettes, one or more ropes (20, 30) can be arranged across or around the wall (10). In some examples, they can be attached to the surface of the wall (10) using a suitable form of fixing means, such as the illustrated rings (21 and 31). The fixing means or rings may be spaced relatively evenly along the length of one or more ropes (20, 30), to keep the rope in a relatively close arrangement to the surface of the wall (10). However, the ropes (20, 30) may be merely retained around the circumference of the wall (10) by tension, especially where the ropes extend around the circumference or boundaries of the structure to be insulated, especially in the example of substantially round tanks, for example. The ropes (20, 30), are described in the following as "ropes", however, that term should not be considered to be limiting to a rope in particular. Other suitable means would include elongate members such as straps, bars, tubes, bungee cords, elastic or inelastic elongate items, or any other elongate member which can be attached to the surface of the wall in a similar manner to a rope. The term "rope, strap or shock-cord" in the present specification should be considered to encompass any of those examples.

The detail of the interlocking of the adjacent cassettes will be described in greater depth in relation to the following figures. However, in figure 1 it can generally be seen that the cassettes can comprise, on a lateral side, one or more lips or tongues (101, 201, 301 and 401), which can be configured to engage with corresponding slots provided on opposing edges of adjacent cassettes. For example, tongue (101) of cassette (100) is engaged in a corresponding slot or channel in cassette (200). A similar arrangement of tongue (301) in a slot or channel in cassette (400) is also illustrated in the same way by dashed lines. These interlocking features, as will be described in greater detail in relation to the following figures, allow the cassettes to engage and interlock with one another as they are installed. This helps facilitate ease of installation of the system and also helps to ensure that the system remains securely installed once in place. As can be seen in relation to the illustrated modules (200 and 400), each module is provided with a rope attachment portion (202, 402), which is configured to enable the insulation cassette (200, 400) to be attached to a rope (20, 30) attached to/around the wall (10). This enables secure attachment of the cassettes during installation, and also assists in secure retention of the cassettes once the full modular system has been installed.

Each cassette may comprise a compliant portion (103, 203, 303, 403) allowing the cassette to be bent in its major plane- i.e. allowing the major wall of the cassette to be bent to provide a bent or curved form to the cassette. One or more of these compliant regions may be provided, so that the cassette can conform to a curvature in the wall (10), thus allowing a curved wall or irregular wall (10) to be insulated using the cassettes. As will be understood from figure 1, in order to enable the major face of each cassette to bend in the compliant portions as illustrated, a further compliant, or extendible portion can be provided in the minor walls (104 and 204) of the cassettes (100 and 200) as shown in the figure. This compliant, compressible or extendible portion (105, 205) can be provided in the form of a pleated, fan-like part as illustrated in figure 1. Alternatively, other means may be provided, such as a rubberised or elasticated portion of the minor wall (104, 204), or by providing cuts or overlapping portions of the minor wall in these regions. The compliant, compressible or extendible region (105, 205) may be provided at a particular point on the length of a wall (104, 204) of the cassette as illustrated, or may alternatively extend along a longer portion of the wall (104, 204), or along the full width of the wall (104, 204), to permit curvature to be applied to the panel up to its full width along the wall (104, 204). This can enable the panel to follow the curvature of the item to which it is mounted.

As will be described later, the cassettes will be in most cases bonded, sealed or cold- welded along their interface lines (106, 107, 206, 207, 306, 307, 406, and 407) where they interlock and abut one another as shown in figure 1. This creates a substantially watertight and hermetic shell covering the wall (10) and so the protective function of the minor walls (104 and 204) is primarily to prevent dust, dirt or fluid ingress during installation. Therefore, these minor walls need not be as substantial or as thick or strong as the major walls of the modules which are substantially parallel to the wall (10).

The shell defining the major and minor walls of the cassettes is generally rigid and made from a stiff sheet or moulded/extruded thermosetting or thermoplastic polymer materials. Suitable materials include a fibre reinforced matrix, otherwise known broadly as composite materials. Examples include GRP (glass reinforced plastic) or / GRE (glass reinforced epoxy), polymeric material (including polyurea etc.) formed from sheet materials, in varying thicknesses according to the specific design requirements of a particular implementation, or by an extrusion or moulding process with e.g. thermoplastic materials. Kevlar™ and/or other veil inclusion materials could also be incorporated in varying combinations. For certain implementations, metal sheet materials could be used to form the cassettes. Certain panels can be manufactured from ultraviolet (UV) cured GRP sheet. In volume production, the cassette manufacturing process may be substantially or mostly automated. Many cassettes could be formed of some combination of polymer or plastics material that will be set and cured to be rigid or at least in a semi rigid state within the cassette structure.

The outer surfaces of the cassettes may have any suitable appearance or coating, as required by the chosen application, such as company livery, brick, cobble or other art. Functional elements such as photovoltaic cells may further be applied to the cassettes in particular where applied to a roof. Sensors such as temperature, humidity, vibration sensors etc. may be integrated into the cassettes, which may be used in an intelligent building management system.

A more detailed illustration of the interlocking features of the cassettes will now be described in relation to the following figures.

Figures 2 to 4 show sequential steps in the offering up and interlocking of adjacent insulation cassettes. As can be seen in figure 2, a first insulation cassette (100) and a second insulation cassette (200) are aligned such that the "tongue" (101), which is a generally planar projection, projecting from a minor side wall of the first insulation cassette (100), can be received in the slot, channel or groove (210) of the second cassette (200). A channel (130, 230) provided on the upper side in the figure of each of the two adjacent insulation cassettes can also be seen. As will be evident from the description of later figures, this is for receiving a projecting portion of the insulation cavity provided in the cassette which will be installed above those cassettes as viewed in the figure.

Figure 3 illustrates an intermediate stage in the installation, where the projection or lip (101) of the first cassette (100) is partially received in the slot, groove or channel (210) of the second cassette (200). At this stage, if required, adhesives, cements or cold welding materials may be introduced to ensure the modular construction of the individual cassettes is rendered more water or air tight. Figure 4 illustrates a final step in which the adjacent cassettes have been brought completely together and where the major front walls meet at an interface line (106). Either at this point or later in the process, the adjacent major front walls of the first and second modules can be sealed with a suitable sealant so that there is no possibility of water ingress into the insulation cavities of the insulation cassettes behind their major walls if required.

Figures 5 to 7 illustrate the introduction of a further insulation cassette (500) into engagement with the first and second cassettes (100 and 200). As can be seen, an interconnecting junction node (550) of the insulation cavity within the cassette (500) is configured such that when introduced from the direction shown in figure 5 (i.e. from above in this arrangement, or from a direction perpendicular to the direction of the introduction of the second cassette (200) into engagement with the first cassette (100), the interconnecting junction node (550) is received in the recipient channel (130) of the first cassette (100). Adjacent to the recipient channel (130) of the first cassette there is provided a further interconnecting junction node of the insulating cavity of the first cassette (100), which is defined by a step (141) in the minor wall of the cassette (100). The recipient channel (130) is defined between the step (141) and the tongue or lip (131) projecting laterally from the minor wall of the cassette (100). As will be appreciated, when the interconnecting junction node or overlapping portion of the cavity (550) of the module (500) is introduced into the recipient channel (130) of cassette (100), then the overlapping portions or otherwise termed intimate steps (140 and 550) of the adjacent cassettes create interconnecting junction nodes or overlapping portions of the respective insulating cavities. This creates a more effective insulation system, by removing any direct heatpath for heat egress or ingress between insulation cavities of the cassettes.

Figure 6 shows an intermediate step in which the cassette (500) has been introduced into deeper engagement with cassette (100).

Figure 7 shows a final step in which the cassette (500) has been brought into complete engagement with the cassette (100). As with the earlier description, a bonding or sealing step will have been, or can be carried out along the join line (507) to create a hermetic seal to prevent water ingress through that interface if so desired. The rope attachment portion (502) can be most clearly seen in figure 7. In this example, the rope attachment portion comprises a corrugated strip, comprising openings (508, 509) in each corrugation, such that an attachment band such as a tie, string or other attachment means can be provided to attach the rope attachment portion (502) to a rope, such as the ropes (20, 30) shown in figure 1, to retain the insulation cassette (500) in place.

Figure 8 shows a cross-section of a cassette when viewed from 'above', when considering the orientation of the cassettes shown in the preceding figures. As can be seen, the shell of the cassette (100) comprises a major wall (111). This major wall extends substantially across the full width of the cassette in the region between the respective channels, tongues, grooves and slots provided at its lateral edges. As can be seen, a first lateral side (160) of the insulation cassette is configured so that an overlapping portion or otherwise termed, a stagger node, (161) of the insulation cavity extends adjacent the wall to be insulated. Further, a second lateral side (170) of the cassette is configured to provide a corresponding overlapping portion or interconnecting junction node (171) of the insulation cavity, which extends adjacent the major wall (111) of the shell of the cassette to provide interlocking insulation cavities when adjacent modules are installed adjacent one another and/or brought into intimate contact. As can be seen in the figure, a wrap, tie or string or other fixing means (80) can be passed through the openings (108 or 508, 109 or 509) of the rope attachment portion (102) to secure the cassette (100) to the wall (10) via the rope. The insulation cavity is generally defined as the area (125) enclosed by the major and minor walls within the cassette (100). This cavity can be filled with an insulation material of any suitable kind as generally known in the art of thermal insulation materials. A selection of options include fibre materials such as fibre glass, rock wool and slag wool, cellulose and/or natural fibres or any mixture of these. Rigid foam boards can also be used, optionally in combination with reflective foils to provide radiant barriers and all of these can be selected as desired for the installation in question. At the first end (160) of the cassette (100), a recipient channel (162) is provided, and this is defined by a step (163) provided in the minor wall (164), and a lip or tongue (101) is provided such that it will enter a corresponding channel or groove (110) in the opposite lateral side of an adjacent module when installed against a further cassette (100).

Figure 9 illustrates in greater detail how a first lateral side (160) of an insulation cassette (100) is configured to interlock with a second lateral side (270) of a second insulation cassette (200). As will be appreciated, when the cassettes are brought together in the direction of the illustrated arrows (91 and 92), the tongue or lip (101) will be received in the corresponding channel or groove (210). Further, overlapping portions or interconnecting junction nodes (271) of the insulation of the second module (200) will be received in the recipient channel (162) of the first module (100), while a corresponding or stagger node (161) of the insulation cavity (125) of the first cassette (100) will be received in the corresponding stagger cavity (161') within the second cassette (200). In this way, the tongue (101) and groove (210) can provide a secure mechanical interlock between the adjacent cassettes. Additionally, or alternatively, the overlapping portions or nodes and recipient channels (161 and 271) of the insulation cavities provide an improved thermal insulation function. The mechanical interlock provided can generally be described as being engageable by translation of the cassettes parallel to the major wall. They can also be arranged to substantially prevent movement of the modules in a direction perpendicular to the plane of the major wall.

Figure 10 illustrates a side view of the engagement of a lower edge (580) of cassette (500) with an upper edge (190) of cassette (100) already described in relation to figures 5 to 7. As can be seen, similarly to the lateral sides, complementary interlocking portions of the insulation cavity (550) of the further cassette (500) and the abutting portion (191) of the insulation cavity (125) of the first cassette (100) are provided, such that when the interconnecting junction node or overlapping portion (550) is received within the recipient channel (130) of the first cassette, an overlap or interconnect is created between the respective insulation cavities (125 and 525) of the adjacent insulation cassettes. Further, similarly to on the lateral sides, a tongue, lip or projection having a substantially planar form (131) is received in a slot or groove (582) to provide a mechanical interlock between adjacent cassettes. This is preferably provided in addition to the interconnecting junction or overlapping portion (550) being received in the recipient channel (130), which provides the non-linear thermal path between the insulation cavities provided by the adjacent cassettes. The rope attachment portion (502) can comprise one or a plurality of corrugations, configured to extend at least partially around one side of the rope to allow the rope to rest against the wall (10) and within a corrugation of the attachment portion as can be seen from feature (502) in Figure 10.

The above examples have been described in relation to a substantially vertical installation of the system for illustrative purposes. However, it will be appreciated that the system could be installed horizontally on a ground or ceiling of a structure. To avoid ambiguity in a non-vertical installation, the previously described top and bottom edges (580 and 190) may be considered third and fourth lateral sides, while the lateral sides discussed in relation to the above (160 and 270) can be considered first and second lateral sides. The invention is therefore not intended to be limited in any way to only systems which are installed on vertical walls. Indications such as top, bottom, upper and lower in the above are merely provided for clarity of the illustration. Similarly, although the ropes (20 and 30) and their corresponding attachment portions (202 and 402) are shown with the ropes extending in a substantially horizontal direction, with the attachment portions being attached thereto and provided on vertically extending sides of the cassettes, alternative configurations can be envisaged with the ropes extending in substantially any direction and the attachment portions (202, 402) of the cassettes (400 and 200) can be provided on any lateral side of the cassettes as necessary for the particular installation.

Figure 11 provides a simplified schematic diagram depicting a shell 1101 for forming a cassette in accordance with certain embodiments of the invention.

The shell 1101 generally corresponds in configuration to the shell of the cassette described previously with reference to Figure 1 except that a first minor wall 1102 and opposite second minor wall 1103 comprise compliant regions which substantially extend their entire width (that is, the compliant region of the first minor wall 1102 extends from one end of the first minor wall 1102 to the other; and the compliant region of the second minor wall 1103 extends from one end of the second minor wall 1103 to the other).

The compliant region 1104 of the first minor wall 1102 and the compliant region 1105 of the second minor wall 1103 consist of a plurality of cut-out sections that form a plurality of fingers. As will be understood, because the distal "tips" of these fingers can move relative to each other, this allows the major wall 1106 of the shell 1101 to be bent in its major plane. As described previously, advantageously, this enables the cassette to conform to the shape of the wall to be insulated.

In contrast to the cassettes shown in Figure 1, there is no requirement for discrete compliant regions 103, 203, 303, 403 to be provided in the major wall 1106 of the shell of the cassette because the compliant regions 1104, 1105 extend along the length of the minor walls 1102, 1103 enabling the major wall 1106 to be bent continuously along its major plane. This enables the cassette to conform more closely to the shape (e.g. curvature) of the wall and strengthens the major wall 1106 as there is no need to add compliant regions of the type depicted in Figure 1.

Figure 12 provides a simplified schematic diagram depicting a first view of the shell 1101 viewed looking toward the first minor wall 1102 and showing in more detail the compliant region 1104 of the first minor wall 1102. Figure 13 provides a simplified schematic diagram depicting a first view of the shell 1101 viewed looking toward the first minor wall 1102 and depicting the insulation 1301 (shown with hatching) when inserted to the shell 1101.

Figure 14 provides a simplified schematic diagram depicting a section 1401 of the shell 1101 that forms the first minor wall 1102 providing a more detailed view of the plurality of cut-outs 1402 that form the fingers 1403 of the compliant region 1104.

As can be seen from Figure 14, the first minor wall 1102 comprises a plurality of further fingers 1403 that project into the shell that are configured to assist in retaining and securing in place the insulation mounted in the shell when the cassette is assembled.

Figure 15 provides a simplified schematic diagram depicting a view of the shell 1101 viewed looking toward the second minor wall 1103 and depicting the insulation 1301 (shown with hatching) when inserted to the shell 1101.

Figure 16 provides a simplified schematic diagram depicting a section 1601 of the shell 1101 that forms the second minor wall 1103 providing a more detailed view of the plurality of cut-outs 1602 that form the fingers 1603 of the compliant region 1105. As can be seen from Figure 16, the second minor wall 1103 comprises a plurality of further fingers 1604 that project into the shell that are configured to assist in retaining and securing in place the insulation mounted in the shell when the cassette is assembled.

As can be appreciated by comparing, for example Figures 14 and 16, the section 1401 of the shell 1101 that forms the first minor wall 1102 has a stepped profile (as can be seen also in Figure 13) so that, when in use, it can receive the section 1601 of the shell 1101 of a vertically adjacent cassette.

Figure 17 provides a simplified schematic diagram depicting a block of insulation material 1701 configured to be fitted to the shell 1101 to form a cassette in accordance with an embodiment of the invention. As can be seen, the block of insulation material 1701 has mounted thereto a plurality of studs 1702a, 1702b, 1702c, 1702d. The studs can be formed by any suitable means as would be apparent to the skilled person. In certain embodiments for example, insulation piercing pins are held using spring fix washers and appropriately capped. This forms a standoff insulation system. In use, the studs face towards the wall to be insulated and ensure spacing the block of insulation material 1701 and the wall which limits any build-up of moisture between the wall and the cassette.

As can be seen from Figure 17, the block of insulation material 1701 has a stepped configuration so that it can fits in the insulation cavity formed by the shell 1101.

As will be appreciated from the above description, any or all of the features described above in relation to the various cassette configurations can be combined in any suitable configuration and the particular examples described are not intended to be limiting on the scope of protection. The scope of protection is rather defined by the scope of the appended claims.