AU735959B2 - An insulation panel - Google Patents

Description

"Tw.

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT 0 0 0 0.00.

00.:.0 o o: Applicant(s): INSULATION SYSTEMS AUSTRALIA PTY LTD Invention Title: AN INSULATION PANEL The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 AN INSULATION PANEL The present invention relates to an insulation panel particularly, though not exclusively, for use as thermal insulation in the ceiling space of a building.

In broad terms there are four major types of thermal insulation for domestic or industrial use: fibreglass batts; polyester batts; cellulous fibre infill; and wool infill. Batts (fibreglass and polyester) are often made in the shape of rectangular blocks that fit between ceiling joists or, for vertical walls, between wall support beams. Batts typically come in several standard sizes and an installer will insert a number of batts between adjacent joists to fill in a ceiling space. When a single batt or a number of batts cannot completely fill the space between a set ofjoists, another batt would typically be cut to the appropriate size and shape to fill any remaining void.

Fibreglass is not liked by any sector of the market because of its perceived risk to the health of its manufacturers, stockists, installers and end users. The benefits of fibreglass are its relatively low cost and its huge product range to protect both thermal and acoustic energies in a wide range of ambients. It is currently the most acceptable insulation product for general industrial/commercial use, being less expensive than polyester and easier to install with no screw bindings as often experienced with polyester batts.

Polyester batts have been poorly promoted (in comparison to fibreglass) and have a relatively small market share. Short comings of polyester batts include its high price, its difficulty to screw through, its limited temperature application range when compared with fibreglass and the general lack of ability to meet the thickness (R ratings) often demanded.

Cellulous fibre infill is the leading domestic insulation material. It is manufactured from newsprint and has a mix of boric acid and borax added to it as fire retardants. It is manufactured in a factory and transported to site in bags. These bags are discharged into a hopper and blown up a tube into the roof space. Limitations include its inability to hold on steep sloping ceilings and its tendency to blow around in the roof space (at an additional cost, a membrane spray is available to help reduce this effect). Poor installation is 3 common where dust penetrates the living space of the home. This dust can cause health problems or exasperate existing ones such as asthma, as well as add to the cleaning burden of the house keeper. Also, it does not recover from contact with water and cannot be installed by the house owner as a DIY project and is excluded from most commercial market applications. It is however very inexpensive and as a result has become the leading domestic insulation material.

Wool infill gained popularity in the wake of mounting wool reserves and smart marketing portraying it as a natural environmentally friendly insulation choice. However when due 10 consideration is made regarding the scouring of the wool in concentrated acid, its lack of .i batt form making it unusable as an industrial product, its attractiveness to vermin and its ~very poor fire rating, it becomes a very poor choice. It is relatively expensive and although cheaper mixes are becoming available they have reduced fire retarding properties.

It is known that heat is transferred by three mechanisms: conduction, convection and radiation. Each of the abovementioned products operates primarily by acting as a conduction barrier to heat from a ceiling space to a living area.

SIt is an object of the present invention to provide an alternate form of insulation forming both a conduction and radiation barrier to the transfer of heat.

S"According to the present invention there is provided an insulation panel including at least: a layer of a thermal insulating material; a gas layer adjacent said layer of thermal insulating material; and, a flexible outer layer forming a sealed package containing said thermal insulating material and said gas layer.

Preferably said panel further includes a layer of low emissivity material adjacent said gas layer.

Preferably said low emissivity layer is supported on an inside surface of said outer layer.

-4- Alternately said low emissivity layer is supported on an outside surface of said outer layer.

Preferably said low emissivity layers is made from or contains aluminium.

Preferably said gas layer is air.

Preferably said outer layer is a sheet of plastics material.

In yet a further embodiment said sealed package is made from a low emissivity material.

Preferably said thermal insulating material is made of a cellulous based material; or :...:mineral fibres; or foam plastics or rubbers; or a combination of any two or more thereof.

oooo• Most preferably said thermal insulating material is loose cellulose fibre.

According to a further aspect of the present invention there is provided an insulation panel including at least: a sealed package of flexible material defining a first volume; a second volume of thermal insulating material contained in said seal package; and :a third volume of a gas contained in said seal package; S"where the sum of said second and third volumes is the same or less than the first volume.

Preferably said third volume is of a sufficient magnitude to provide a layer of said gas between said thermal insulating material and in inner surface of one side of said package where said panel is tied down on an opposite side of said package.

According to a further aspect of the present invention there is provided an insulation panel comprising at least: a bottom layer of a thermal insulating material; a gas layer above said bottom layer; and, 5 a layer of a low emissivity material above said gas layer; and a flexible outer layer forming a sealed package containing said bottom layer and gas layer, and supporting said low emissivity later; whereby, in use, heat transfer through said panel requires heat to be absorbed by said low emissivity layer, radiated by said low emissivity layer across said gas layer, and conducted through said bottom layer.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a front view of a panel in accordance with a first embodiment of the present invention; *Figure 2 is a perspective view of the panel shown in Figure 1; Figure 3 is a section view of a second embodiment of the present invention; and Figure 4 is a plan view of a planar sheet utilised in the manufacture of the panel depicted in Figures 1 and 2.

Referring to the accompanying drawings, a first embodiment of the insulation panel S" comprises a bottom layer 12 of a thermal insulating material, ie a thermally non conductive material, a gas layer 14 above the bottom layer 12, and a layer 16 of a low emissivity material above the gas layer 14. The layers 12, 14 and 16 are all wrapped or contained in an outer packaging layer 18 so that the panel 10 assumes a rectangular shape as depicted most clearly in Figure 2. The bottom layer 12 can be made from any conventional thermal insulating material such as cellulous infill, wool infill, fibreglass batts or free fibres; polyester batts or free fibres; and foamed iubber or plastics material such as polystyrene foam.

Most conveniently, the gas layer 14 is an air layer. In one embodiment, the gas layer 14 is about 10% of the thickness/depth of the bottom layer 12. However, the specific percentage 6 of gas layer thickness to bottom layer thickness is of itself not critical. What is of importance is that the gas layer is of sufficient depth to ensure that heat transfer from the layer 16 to the bottom layer 12 is predominantly by radiation of heat from the layer 16, rather than by conduction. The low emissivity layer 16 will typically be in the form of a film or web of aluminium or material containing aluminium that is fixed to the inside of the outer layer 18. The layer 16 is positioned to lie above the gas layer 14 and occupy substantially the whole area of the upper surface 20 of the panel The outer layer 18 is made from a flexible material such as a plastic film or sheet 22 (depicted in Figure 3) on which the layer 16 is deposited, fixed or otherwise supported.

Typically the sheet 22 would be in the form of a roll and the layers 16 will be formed inboard of the edges of the sheet 22 and spaced apart in a lengthwise direction. In manufacture, it is envisaged that the sheet 22 will be passed through a wrapping machine and wrap around a body or volume of insulating material to form the layer 12, simultaneously capturing and enclosing a volume of air to form the gas layer 14 and then sealed. During this process, the sheet 22 is wrapped in a manner to ensure that the low emissivity layer 16 is formed across the upper surface 20 of the panel 10 and spaced from the bottom layer 12 via the air layer 14. The sheet 22 is sealed together at respective spaced apart locations slightly inboard of each of its longitudinal edges so as to form a depending tag 24 running longitudinally down the middle of bottom surface 26 of the panel 10. The tag 24 thus acts as a locating means for installers to ensure correct .o orientation of the panels 10. The correct orientation being that the panel 10 is laid so that it sits on the tag 24. This is of course achieved by ensuring that the tag 24 is formed on the same location on each panel When in use, the panels 10 are located between joists in a ceiling space of a building. Heat building up in the ceiling space would be absorbed mainly by conduction but also partly by convection by the low emissivity layer 16. Because the layer 16 has a low emissivity, it tends to retain the heat absorbed rather than radiate the heat. Nevertheless, some heat will be radiated by the layer 16. This radiated heat must traverse the air gap 14 prior to acting on the bottom layer 12. Some of the heat absorbed by layer 16 is also transferred by convection through air gap 14 to the layer 12. However, the insulating properties of the air -7layer 14 reduce the heat transfer to the bottom layer 12. Additionally, the bottom layer 12 being a very poor thermal conductor limits the transfer of heat through the remainder of the panel.

In one embodiment, the panel 10 would have a width W of 480 mm, depth D of 100 mm and a breath B of 205 mm. In this way, the panel 10 could be used to fit the three most commonly used joist spacings.

Figure 3 depicts a further embodiment of the panel 10'. The panel 10' includes a sealed package 18' of flexible material that defines a first volume. A second volume of thermal insulating material 12' is contained within the package 18'. Typically the thermal insulating material 12' is loose cellulose fibre. The panel 10' also includes a third volume of gas which is contained within the sealed package 18'. The sum of the volume of thermal insulating material 12' and the volume of gas is arranged to be the same as or less 15 than the volume of the sealed package 18'. In the illustrated embodiment, there is sufficient volume of gas to create a gas layer 14' within the panel 10'. The gas layer 14' is between the thermal insulating 12' and an inner surface of a side 20' of the package 18' when the panel 10' is laid on its opposite side 22'. The panel 10' is in the general shape and configuration of a pillow. In a departure from the embodiment of the panel 10 depicted in Figures 1 and 2, the provision of a layer of low emissivity material 16' on the inner surface .i of the package 18' is optional. In its most basic form, the low emissivity layer 16' can be deleted altogether and for this reason is depicted in Figure 3 in phantom line. Thus the broad configuration of the panel 10' is of a sealed package 18' containing thermal insulating material 12' and a volume of gas. The gas may reside solely within the volume of the thermal insulating material 12' in which case the sum of the volume of the insulating material 12' and the volume of gas is less than the volume of the package 18'. To manufacture a panel 12' in this configuration however a greater volume of insulating material 12' will be required and/or it will be necessary to evacuate some of the gas (typically air) from the sealed package 18'. Such configuration is not preferred as it is believed that the thermal rating of such a panel will be lower than a panel where there is sufficient gas to create the gas layer 14'.

8 In a further embodiment, a layer of low emissivity material 16" can be formed on the outside surface of the sealed package 18' instead of on the inside of package 18'. Ideally, when the low emissivity layer 16" is on the outside it is also formed with a reflective surface so as to reflect infra-red radiation.

In yet a further alternative the whole of the package 18' can be made from a low emissivity layer. One further alternative configuration is where only the side 20' of the package 18' is formed as a sheet of low emissivity material.

Now that an embodiment of the invention has been described in detail it will be apparent to those skilled in the relevant arts that numerous modifications and variations may be made without departing from the basic inventive concepts. For example, the outer layer 18 can be made from any sheet of plastics or paper material that is flexible and ideally is fire retardant. The outer layer 18 can be printed with advertising material or other matter.

Preferably the outer layer 18 is also impervious to water and air so as to maintain the layer 14. The panel 10 can be made from shapes and in dimensions other than the rectangular block depicted in Figure 2. While aluminium is preferred as the material from which the layer 16 is made any other low emissivity material can be used. Also if desired gas can be injected into the panel 10 instead of, or in addition to, it being captured within outer layer 20 18 during the wrapping of bottom layer 16.

a.

All such modifications and variations are deemed to be within the scope of the present invention the nature of which is to be determined from the above description and the appended claims.

Claims (19)

1. An insulation panel including at least: a layer of a thermal insulating material; a gas layer adjacent said layer of thermal insulating material; and, a flexible outer layer forming a sealed package containing said thermal insulating material and said gas layer.

2. The panel according to claim 1 further including a layer of low emissivity material adjacent said gas layer.

3. The panel according to claim 2 wherein said low emissivity layer is supported on an inside surface of said outer layer.

4. The panel according to claim 2 wherein said low emissivity layer is supported on an outside surface of said outer layer.

5. The panel according to claim 1 wherein said sealed package is made from a low emissivity material.

6. The panel according to any one of claims 2-5 wherein said low emissivity "layers is made from or contains aluminium.

7. The panel according to any one of claims 1-6 wherein said gas layer is air.

8. The panel according to any one of claims 1-4 wherein said outer layer is a sheet of plastics material.

9. The panel according to any one of claims 1-8 wherein said thermal insulating material is made of a cellulous based material; or mineral fibres; or foam plastics or rubbers; or a combination of any two or more thereof.

10 The panel according to any one of claims 1-8 wherein said thermal insulating material is loose cellulose fibre.

11. An insulation panel including at least: a sealed package of flexible material defining a first volume; a second volume of thermal insulating material contained in said seal package; and a third volume of a gas contained in said seal package; where the sum of said second and third volumes is the same or less than the first volume.

12. The panel according to claim 11 wherein said third volume is of a sufficient .magnitude to provide a layer of said gas between said thermal insulating material and in inner surface of one side of said package where said panel is tied down on an opposite side of said package. *o .o

13. The panel according to claim 12 further including a layer of low emissivity material adjacent said gas layer. o•

14. The panel according to claim 13 wherein said low emissivity layer is supported on an inside surface of said outer layer.

The panel according to claim 13 wherein said low emissivity layer is supported on an outside surface of said outer layer.

16. The panel according to claim 12 wherein said sealed package is made from a low emissivity material.

17. An insulation panel comprising at least: a bottom layer of a thermal insulating material; a gas layer above said bottom layer; and, a layer of a low emissivity material above said gas layer; and 11 a flexible outer layer forming a sealed package containing said bottom layer and gas layer, and supporting said low emissivity later; whereby, in use, heat transfer through said panel requires heat to be absorbed by said low emissivity layer, radiated by said low emissivity layer across said gas layer, and conducted through said bottom layer.

18. An insulation panel according to any one of Claims 1-10 and 17 wherein said sealed package is formed with a tag on an exterior of said package wherein said tag is formed at the same location on each panel.

19. An insulation panel substantially as herein described with reference and as illustrated in the accompanying drawings. DATED this 24 h day of May 2001 INSULATION SYSTEMS AUSTRALIA PTY LTD by their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark SAttorneys of Australia.