This invention relates to an insulation system (and parts thereof), to insulation panels and to a method for fixing panels, notably insulation panels, at a support structure; it is particularly suited to External Thermal Insulation Composite Systems (ETICS).

Insulation panels are commonly fixed at a support structure, for example at an external wall of a building, to provide an external cladding. The support structure is seldom perfectly flat or perfectly planar. In the case of an external wall such irregularities may include a waviness of the external surface rather than perfect planarity, protrusions at the external surface due to excess or overflow of cement or mortar and inclination of the external wall rather than perfect vertical alignment. It is far from easy to correctly align insulation panels at such an imperfect structure.

In order to compensate for such irregularities and create a substantially planar external surface of a facade of attached insulation panels without differences in heights or the presence of steps between individual insulation panels, it is often necessary to sand the external surface of the facade of attached insulation panels. This involves significant work and difficulty to provide a planar external surface. Irregularities in the external surface are often still visible even when the external surface has been sanded and/or has been covered with a layer of render.

One aim of the present invention is to provide improvements in various aspects of systems used to provide insulation panels secured at supporting building structures.

In accordance with one of its aspects, the present invention provides a method of fixing an insulation panel at a supporting structure as defined in claim 1. Additional aspects of the invention are defined in other independent claims. The dependent claims define preferred and/or alternative embodiments.

Preferably, once fixed to the support structure, insulation panels do not have their external surfaces partially removed, for example by sanding, in order to remove steps between adjacent insulation panels and/or to improve planarity between insulation panels. The general tolerance for form and position (DIN ISO 2768 T2) of the external surfaces of a plurality of adjacent insulation panels according to the invention preferably conforms with class L, more preferably class K and even more preferably class H as defined in ISO 2768 published in 1989.

For example, particularly for an ETICS system, for the external surface of insulation panels when secured at the support structure: • The long range planar deviation measured using a 2m long ruler may be < 5mm, preferably < 3mm; and/or

• The short range planar deviation measured using a 0.2 m long ruler may be < 3mm, preferably < 2mm; and/or

· The deviation from true vertical may be a) < 8mm over a distance of 2.5 m and/or b) no more than one eighth of the cubic-root of the full height of the assembled insulation panels over the full height of the assembled insulation panels.

The invention may be used to compensate for long-range and/or short-range deformations and/or deviations from true vertical at the support structure. The external surface of a plurality of insulation panels in accordance with the invention may be more planar that the support structure.

The support structure may be: an external surface of a wall, particularly the external surface of an external wall of a building and more particularly that of a brick or breeze block wall; the internal surface of a wall of a building; or a roof. The support structure may be a portion of the said surface.

Preferably, the system does not rely upon an adhesive to secure the insulation panel to the supporting structure; more preferably no adhesive is used to secure the insulation panel to the supporting structure.

The insulation panels are preferably thermal insulation panels having a lambda value (λ) of less than 65 mW/m.K, less than 50 mW/m.K, less than 45 mW/m.K or less than 40 mW/m.K, more preferably a lambda value (λ) of less than 35 mW/m.K or less than 33 mW/m.K. Preferably, the insulation panels comprise at least two layers assembled together: a compressible layer and in an incompressible layer. The compression strength and/or Young's modulus in compression of the compressible layer is less than the compression strength and/or Young's modulus in compression of the incompressible layer. The term "compressible layer" designates a layer which is substantially compressible in that its thickness may be substantially compressed as used in the invention to compensate for irregularities at the surface of the support structure, for example, it may be compressed by at least 5 mm, by at least 10 mm, by at least 15mm, by at least 20 mm, by at least 25 mm or by at least 30mm. The term "incompressible layer" designates a layer which is substantially incompressible in that its thickness remains substantially uncompressed as used in the invention, for example, it may be compressed by less than 5 mm, by less than 3 mm or by less than 2 mm.

The compressible layer is adapted to be placed in contact with a surface of the support structure and to be at least partially compressed so as to compensate for i) any long-range irregularities or deformations (notably irregularities or deformations occurring over a distance of at least 30 cm) and/or ii) any short-range deformations (notably irregularities or deformations occurring over a distance of less than 30 cm) at the surface of the support structure.

The compressible layer may:

• comprise or consist essentially of mineral wool, notably: i) glass mineral wool, more notably glass mineral wool having a density of at least 10 kg/m ³ or at least 15 kg/m ³ and/or a density of not more than 30 kg/m ³ or not more than 25 kg/m ³ ; or ii) rock mineral wool, more notably rock mineral wool having a density of at least 20 kg/m ³ or at least 25 kg/m ³ and/or a density of not more than 80 kg/m ³ or not more than 70 kg/m ³ ; and/or

• comprise or consist essentially of a compressible polymeric foam; and/or

• have a compression strength of not more than 20 kPa, not more than 15 kPa, not more than 10 kPA or not more than 8 kPa; and/or

· have a lambda value of not more than 0.065 W/m.K, not more than 0.050 W/m.K, not more than 0.045 W/m.K, not more than 0.040 W/m.K, not more than 0.038 W/m.K; not more than 0.035 W/m.K, not more than 0.033 or not more than 0.032 W/m.K; and/or

• have a thickness in its uncompressed state which is at least 8mm, at least 10 mm, at least 15 mm, at least 20mm, at least 30 mm, at least 40mm or at least 50 mm;

and/or

• have a thickness in its uncompressed state which is not more than 120 mm, not more than 100 mm, not more than 80 mm, or not more than 60 mm.

The incompressible layer may:

· comprise or consist essentially of: a mineral wool, notably stone wool, for example stone wool having a density of at least 80 kg/m ³ , at least 100 kg/m ³ or at least 120 kg/m ³ and/or having a density of not more than 220 kg/m ³ or not more than 200 kg/m ³ ; and/or

• comprise or consist essentially of substantially incompressible polymeric foam; and/or

• comprise or consist essentially of expanded polystyrene (EPS), notably EPS having a density of at least 15 kg/m ³ or at least 20 kg/m ³ and/or a density of not more than 50 kg/m ³ or not more than 40 kg/m ³ ; and/or • comprise or consist essentially of extruded polystyrene (XPS), notably XPS having a density of at least 20 kg/m ³ or at least 25 kg/m ³ and/or a density of not more than 65 kg/m ³ or not more than 60 kg/m ³ ; and/or

• comprise or consist essentially of polyurethane (PU), notably PU having a density of at least 20 kg/m ³ or at least 25 kg/m ³ and/or a density of not more than 80 kg/m ³ or of not more than 50 kg/m ³ or not more than 45 kg/m ³ ; and/or

• comprise or consist essentially of polyisocyanurate (PIR), notably PIR having a

density of at least 20 kg/m ³ or at least 25 kg/m ³ and/or a density of not more than 80 kg/m ³ or of not more than 65 kg/m ³ or not more than 60 kg/m ³ ; and/or

• comprise or consist essentially of wood wool for example having a density of at least 160 kg/m ³ and/or not more than 265kg/m ³ ; and/or

• have a compression strength of at least 20 kPa, at least 30 kPa, at least 50 kPa, at least 80 kPa, at least 100 kPa, at least 150 kPa or at least 200 kPa; and/or

• have a lambda value of not more than 0.065 W/m.K, not more than 0.050 W/m.K, not more than 0.045 W/m.K, not more than 0.040 W/m.K, not more than 0.038 W/m.K; not more than 0.035 W/m.K, not more than 0.033 or not more than 0.032 W/m.K; and/or

• have a thickness which is at least 40 mm, at least 45 mm, at least 50 mm, at least 60 mm, at least 80 mm, at least 100 mm or at least 120 mm; and/or

• have a thickness which is not more than 300 mm, not more than 250 mm, not more than 200 mm, or not more than 180 mm.

The compression strengths referred to above represent the force required in compression to provoke a 10% deformation in thickness; such compression strengths are preferably measured in accordance with the appropriate standard currently applicable in the European Union.

The insulation panel may comprise or consist essentially of:

a) a layer of glass mineral wool and a layer of polyisocyanurate;

b) a layer of glass mineral wool and a layer of rock mineral wool;

c) a layer of glass mineral wool and a layer of extruded polystyrene;

d) a layer of glass mineral wool and a layer of expanded polystyrene.

e) a layer of glass mineral wool and a layer of wood wool

f) a layer of glass mineral wool and wood panel

g) a panel of an insulating material of variable density Where EPS is used this may be "white" EPS or EPS comprising graphite, carbon or other additives.

Where mineral wool material is used, in particular for the compressible layer, the majority of the mineral wool fibers may have an orientation substantially parallel to the major surfaces of the mineral wool. Where mineral wool material is used, in particular for the

incompressible layer, the majority of the mineral wool fibers may have an orientation substantially perpendicular to the major surfaces of the mineral wool. Alternatively, the mineral wool material may have fibres randomly organised inside the mineral wool material.

The multiple layers of the insulation panel may be attached together, for example by glue, binder, crosslinking, curing or by mechanical means, or combinations thereof.

The insulation panel may have a length which is at least 50 cm, at least 60 cm, at least 80 cm, at least 100 cm or at least 120 cm and/or which is no more than 180 cm, no more than 160 cm or no more than 150 cm; it may have a width which is at least 20 cm, at least 40 cm, at least 50 cm or at least 60 cm and/or which is no more than 150 cm, no more than 130 cm or no more than 120 cm.

The insulation panel may have at least one pre-drilled hole for a fixation, for example a screw, adapted to secure the panel to the support structure. Preferably, a panel anchor, more preferably an anchor made of a material which is different to that of the insulation panel, is pre-installed along the axis of the pre-drilled hole of the panel. The anchor may be adapted to cooperate with the fixation when the panel is secured to the support structure so as to substantially prevent movement of the panel with respect to the support structure.

In a method of fixing an insulation panel at a support structure, a signal generator, which may be a laser generator, may be secured at the support structure, for example, at one corner of an external wall of a building where this provides the support structure. Preferably, a second signal generator is also secured at the support structure, spaced from the first signal generator. Where the signal generator is a laser generator, it preferably generates a laser beam in the visible portion of the spectrum, for example a red or green laser beam.

In one preferred embodiment, the support structure comprises a continuous surface, for example a wall, and substantially an entire major surface, notably at least 90% of a major surface, of the insulation panel is assembled to be in direct contact with the surface of such a support structure. Thus, in this embodiment there is preferably no gap or spacing between the continuous surface of such a support structure and the insulating panel.

Notably in such a configuration, securing of the panel to the support structure is achieved by a mechanical fastener, particularly a screw, which is secured at the support structure and at the insulating panel without an intervening (e.g. metal) bracket or spacer.

Embodiments of the invention will now described, by way of example only, with reference to the following drawings of which:

Fig 1 is a plan view of an insulation panel;

Fig 2 is a schematic cross section through an upper portion of the insulation panel of Fig 1 ;

Fig 3 is a cross section through a panel anchor;

Fig 4 is a side view of a fixation screw;

Fig 5A and Fig 5B are schematic cross sections through an upper portion of the insulation panel of Fig 1 secured to an external wall of a building;

Fig 6 is a schematic cross-section of apparatus for securing a signal generator to a support structure;

Fig 7 is a schematic perspective view showing assembly of a panel at the external wall of a building;

Fig 8 is a schematic cross-section corresponding to Fig 7;

Fig 9A is a schematic perspective showing long-range imperfections at a support surface; and

Fig 9B is a cross-section showing short-range imperfections at a support surface.

A typical long-range imperfection at an external wall 91 of a building in the form of a waviness 93 is illustrated in Fig 9A; this results in the external surface not being planar (the theoretic planar aspect being illustrated at 92). Generally, when a fagade of substantially entirely rigid known insulation or ETICS panels are assembled at the external wall 91 , for example by using an adhesive to adhere each insulation panel to the external wall 91 , such waviness or non-planarity of the wall 91 will cause a similar undesired waviness or non- planarity at the external surface of the insulation panels.

Examples of short-range or localised imperfections at an external wall 91 of a building are illustrated in Fig 9B in the form of i) imperfect or non-planar alignment of a protruding brick or breeze block 94 whose front surface projects from a general plane of the front surface of one or more adjacent bricks and ii) mortar or cement 95 which projects beyond the plane of the front surface of one or more adjacent bricks. Such imperfections complicate the attachment of traditional insulation of ETICS panels, especially where a surface of a rigid insulation material is to be adhered to the front surface of the wall 91.

One aim of the present invention is to provide an insulation system which can compensate for such imperfections and/or provide a planar insulation facade in spite of such

imperfections.

The insulation panel 10 of Fig 1 has a length L of 80cm and a width W of 40cm. It comprises an outer, incompressible layer 1 1 for example of polyisocyanurate (PIR) or polyurethane (PUR) having a thickness of 80 mm and a density of about 33 kg/m ³ assembled with an inner, compressible layer 12 of glass wool having a density of about 20 kg/m ³ and an uncompressed thickness of 40mm. A bore hole 13 arranged towards each corner of the panel penetrates in to the incompressible layer 1 1 from and perpendicular to its external surface 1 1 1 . In the illustrated embodiment, this bore hole penetrates the entire thickness of the incompressible layer 1 1 and the compressible layer 12.

A panel anchor in the form of a plug 14 is secured within each of the bore holes 13, in this embodiment entirely within the body of the incompressible layer 1 1 , such that the position of the plug 14 with respect to the external surface 1 1 1 of the panel 10 is pre-determined and remains fixed during the operation of securing the panel to a wall. The plug 14 is preferably factory assembled within the panel 10 prior to delivery of the panel to its site of use by drilling a bore hole 13 through the thickness of the incompressible panel 1 1 and using an external screw thread 144 of the plug to advance the plug within the bore and secure it therein in its desired position. External surface 1 1 1 of the incompressible panel 1 1 is used as a datum surface for positioning the plug 14 within the panel 1 1 such that each plug on a single panel, and each plug on each of a series of panels manufactured, is secured and fixed at the same predefined distance with respect to its external panel surface 1 1 1.

A fixation, illustrated in Fig 4, in the form of a screw 16 adapted for use with the panel 10 comprises a head 41 , a first shank portion 42, a circular stop 43 and a second shank portion 44 ending in a tip 45. The stop 43 is spaced from the head 41 by the first shank portion 42 and has the form of a disk having a diameter larger than the first 42 and second 44 shank portions so that the stop 43 is provided with a head facing surface 431 and a tip facing surface 432. The second shank portion 44 comprises an unthreaded portion 441 extending from the stop 43 part way towards the tip 45 and a threaded section 442 extending from the tip 45 part way towards the stop 43.

The plug 14, illustrated in Fig 3, comprises an entry zone 141 , a stop zone 142 and a shank stabilising zone 143. The stop zone 142 of the plug is configured to receive and retain the stop 43 of the screw at a retained position at which advancement or retraction of the screw with respect to the panel 1 1 is prevented whilst rotation of the screw is possible. The shank stabilising zone 143 is adapted to stabilise the orientation of the inserted screw with respect to the plug (and thus with respect to the panel 10) and to minimise lateral movement of the inserted screw when at its retained position. The internal diameter of the shank stabilising zone 143 is preferably cylindrical and provides a close sliding fit with respect to the external diameter of the unthreaded portion 441 of the second shank portion 44 of the screw so as to support and allow rotation of the screw when in its retained position. The entry zone 141 of the plug is configured to facilitate guiding of the screw 16 as its tip 45 is inserted in to and advanced through the plug until the screw reaches its retained position. The entry zone has a resilient, tapered guide 141 1 to facilitate centring of the screw 16 during its insertion in the plug.

Figs 5A and 5B in association with Fig 4 and Fig 3 illustrates the interaction between the screw 16 and the plug 14 when the panel 10 is secured to a support structure 51 provided by a wall.

When the screw 16 is assembled in its retained position within the plug (as illustrated in Fig 5A and Fig 5B), the stop 43 of the screw and the stop zone 142 of the plug engage and cooperate to retain the screw in a predetermined position within the plug and thus in a predetermined position with respect to the external surface 1 1 1 of the panel. In this retained position, the tip facing surface 432 of the stop 43 is retained such that it abuts a tip side stop surface 1422 of the stop zone 142. Interaction between a head side stop surface 1421 of the stop zone 142 and the head facing surface 431 of the stop 43 assists in maintaining this abutment and in preventing retraction of the screw 16 relative to the plug 14. When the screw 16 is in its retained position, the head 41 of the screw is positioned within the insulation panel 10 below the external surface 1 1 1 and the tip 45 and at least part of the threaded portion 442 of the second shank portion 44 of the screw project from an inside surface 1 12 of the panel 10 so as to be able to engage with and retain the screw 16 at a support structure 51 . The position of the plug 14 within the incompressible layer 1 1 and relative to the external surface 1 1 1 is fixed. Consequently, the position of the screw at its retained position is also fixed with respect to the external surface 1 1 1 .

In order to secure the panel 10 to a wall 51 , with the screw 16 arranged at its retained position within the panel 10, the screw it rotated by turning its head 41 so that the threaded portion 442 towards the tip 45 of the screw 16 advances in to the wall 51 . Cooperation between the stop 142 of the screw 16 and the stop zone 142 of the plug 14 causes the panel 10 to advance towards the wall 51 as the screw 16 advances. Once the inside surface 1 12 of the panel 10 contacts the wall 51 , further rotation of the screw causes additional advancing of the external surface 1 1 1 of the panel whilst compressing the compressible glass wool layer 12 of the panel against the wall. The external surface 1 1 1 of the panel 10 may thus be brought to a desired position with the amount of compression of the compressible glass wool layer 1 12 providing a compensation for long-range and/or short-range imperfections of the wall's surface. When so assembled, cooperation between the threaded portion 442 of the screw secured at the wall, engagement between the screw stop 45 and the stop zone 142 of the plug, and the securing of the plug 14 relative to the incompressible layer 1 1 of the panel 10 prevents forward or backward movement of the panel 10 with respect to the wall 51 .

In a preferred method to align a series of individual panels 10 at the surface of a wall 51 so that the external surfaces of each panel are co-planar, the wall 51 is initially scanned and its long-range and/or short-range imperfections are analysed in order to determine a desired plane for the external surface 1 1 1 of the panels 10. At this desired, optimised position, the external surfaces 1 1 1 of the panels will be coplanar, the inside surface 1 12 of each panel 51 will be in contact with the wall 51 and the compressible layer 12 of each panel will be compressed on the wall 51 so as to compensate for or absorb the long-range and/or short- range imperfections of the wall's surface.

In one method, a first laser generator 62 is fixed towards the upper corner of the wall 51 , as shown in Fig 7 via a fixation 61 shown in Fig 6. The fixation 61 comprises an adapter 621 which allows adjustment of the position of a rotating laser beam 624 emitted from a laser source 623, notably its distance from and angle with respect to the fixation 61 . The rotation of the laser beam 624 creates a virtual plane 625 in the form of a disk.

Preferably, a second laser generator 62' is fixed at the wall 51 , spaced from the first laser generator, for example positioned towards the other top corner of the wall, and is adjusted so as to emits a rotating laser beam which defines the same virtual plane 625 as the virtual plane defined by the first laser generator 62. The second laser generator 62 is useful if obstructions, for example the presence of a window sill 71 obscure the laser beam emitted from the first laser 62 at a particular position at the wall.

Once the laser generator(s) have been configured, a first panel 10 without screws 16 is held at a lower corner of the wall 51 with the inside surface 1 12 of its compressible layer 12 in contact with the surface of the wall 51. A hole 72 adapted to receive a wall anchor 52 is drilled sequentially into the wall through each bore 13 of the panel 10 using a drill bit having a shank configured to avoid damaging the plug 14, particularly to avoid damaging the shank stabilizing zone 143 of the plug. The panel 10 is then removed and a plastics wall anchor 52 is lodged in each of the holes 72 in the wall 51 . A screw 16 is inserted into each bore 13 of the panel 10 from external surface 1 1 1 of the panel 10 until the screw is at its retained position, i.e. the stop 43 of the screw and the stop zone 142 of the plug engage and cooperate to retain the screw, blocking the forward and the backward movement of the screw 16 but without blocking the rotation of the screw 16 during the screwing. In this position, the threaded portion of the shank 442 projects from the inside side 1 12 of the panel. Each threaded portion of the shank of the screw 442 is placed inside each wall anchor 52 retained in the wall 51. The head 41 of one of the screws 16 is then rotated using an electric screw driver 81 so as to advance the screw into the wall 51 and secure the threaded portion of the screw inside its wall anchor 52. During rotation of the screw 16, the tip surface 432 of the stop 43 transfers force and forward movement to the tip side stop surface 1422 of the stop zone 142 and, as the screw and panel 10 advance, the

compressible layer 12 is progressively compressed against the surface of the wall.

Preferably, as illustrated in Fig 8, each panel 10 is attached to the wall 51 using an electric screw driver 81 provided with a laser receiver 81 1. Upon detection of alignment between the laser receiver 81 1 and the laser beam 624 defining the virtual plane 625 a control signal is generated by the laser receiver 81 and an associated control system automatically stops rotation of the electric screw driver 81. The remaining screws of the insulation panel are secured in the wall in the same way. When secured in this way to the wall 51 , the external surface 1 1 1 of each panel is coplanar with and arranged at a predefined distance from the virtual plane 625.

Subsequent adjacent insulation panels are attached to the wall in the same way, generally working row by row. The determination of the spacing of each panel from the wall on the basis of the position of its screw heads 41 (and thus the screw stops 43 and the external surface 1 1 1 of the panel) with respect to the virtual plane 625 results in the external surface 1 1 1 of each panel being coplanar.

In this arrangement, the virtual plane 625 serves as a datum used to position each of the insulation panels 10, and more particularly to fix the position and orientation of the external surface 1 1 1 of each insulation panel.

Towards the end of a procedure for assembling a facade of insulation panels 10 at the wall 51 , the laser generator(s) 62, 62' are removed to allow manual securing of a panel at this position at the wall once the other panel have been placed.

A thermal-bridge stop 131 , preferable made of the same material as the incompressible layer 1 1 , may be used to plug an exposed portion of the bore 13 and thus cover each screw head 41 . Once all of the insulation panels 10 of a facade have been secured a facing may be applied to their external surfaces 1 1 1 , for example a facing which is applied wet and allowed to dry. The facing may be a cement render or an acrylic render; it may have a thickness of≥ 2 mm or≥ 3 mm, or≥ 6 mm or≥ 10 mm or≥ 20 mm or≥ 50 mm.

In an alternative, un-illustrated embodiment screws whose tip 45 and/or threaded portion 442 are adapted to allow then to be screwed in to and secured at the wall without pre- drilling and/or without provision of a separate anchor at the wall are used. Such screws may be self-tapping and/or provided with a tip which provides a drill bit. This renders it unnecessary to pre-drill the wall 51 before fixing the panels 10. In one method of using such screws, with an insulation panel held against a wall, a screw is inserted into a bore 13 of the panel 10 such that its tip projects slightly from the compressible layer 12 and is held against the wall with the stop 43 of the screw spaced from and not retained in the stop zone 142 of the plug. Rotation of the screw using an electric screwdriver causes the tip of the screw 16 and the threaded portion 442 to drill the screw in to the wall 51 and to advance the screw within the wall. Once the inside surface 1 12 of the compressible layer 1 12 is in contact with the wall 51 , the screw 16 advances within the plug 14 until the tip surface 432 of the stop 43 of the screw comes contacts the tip side stop surface 1422 of the stop zone 142. Subsequent rotation of the screw results in the screw 16 penetrating deeper into wall 51 and in compressible layer 12 of the panel 10 being compressed against the wall as the external surface 1 1 1 of the panel advances towards the wall. Preferably, rotation of the electric screwdriver 81 is automatically stopped by interaction between the laser beam 624 of the laser generator 62 and the laser receiver 81 1 of the screwdriver 81 when the desired alignment of the external surface 1 1 1 of the panel has been achieved.

The panels may be provided with shiplap joints or other cooperating edge profiles to enhance their abutment and/or cooperation. Joints between panels may be covered, for example using tape, notable self-adhesive tape, subsequent to their assembly at the support structure.

The invention and/or aspects thereof may also be used in relation to ventilated facades, pitched roofs or ceilings.