WO2001069005A1

WO2001069005A1 - Panel

Info

Publication number: WO2001069005A1
Application number: PCT/GB2001/001202
Authority: WO
Inventors: John Thompson
Original assignee: Thermaliner Insulation Systems Ltd.
Priority date: 2000-03-17
Filing date: 2001-03-19
Publication date: 2001-09-20
Also published as: GB0006335D0; WO2001069006A1; EP1280970A1; AU4089601A; CA2403404A1; AU4089901A; AU2001240899B2; US20040020148A1

Abstract

A building panel including a permeable sheet of insulating material (10) fastened to an impermeable sheet of material (13) and having one or more conduits (16) formed in the insulating material and/or channels formed in a surface of the impermeable sheet (13) to allow fluid to escape from between the two sheets of material. The insulating material may be a foam material, and a plurality of substantially parallel, substantially straight, spaced apart channels (16) may be formed in a surface of the sheet of insulating material adjacent the impermeable sheet. The impermeable material may be a plastics material or metal. The impermeable sheet may define a plurality of ribs (14) for supporting building blocks. The two sheets may be bonded together with an adhesive.

Description

PANEL

The present invention relates to a building panel.

A building panel is proposed in GB 2346393A comprising a closed

cell extruded polystyrene foam sheet to which is bonded a building block

support panel vacuum moulded from a high impact polystyrene sheet. The

building block support panel comprises a plurality of hollow ribs for

supporting building blocks. The hollow ribs are open towards the foam

sheet. In use such a panel is used to form the outside of a building. The

panel is positioned with the foam sheet directed towards the inside of the

building and the building block support panel towards the outside of the

building.

The foam sheet provides thermal insulation, and brick slips, or the

like, may be supported on the building block support panel to give the

appearance of a conventional brick, or other block, wall to the outside of

the building.

Closed cell polystyrene foam is permeable, whereas high impact

polystyrene sheet is not. This gives rise to a problem.

A function of the outside wall of a building is to separate the

environmental conditions outside the building from those inside the building.

At least during part of the year in many countries it is desired to maintain

the temperature inside a building higher than that outside the building.

Typically the air inside a building is maintained at a temperature of around 21 °C, and has a relative humidity of around 55%. During winter

months at least the outside air temperature in many countries (typically

Northern Europe and America) remains below 10°C, and the outside air

humidity is variable. As a consequence the water vapour pressure inside a

building is almost always higher than that outside. This causes water

vapour inside a building to end to move through the walls of a building to

reach the outside of the building . It can be that as a consequence of this

movement that condensation occurs on or within the outside walls of the

building.

Where the outside walls of a building are formed from panels of the

type disclosed in GB 2346393A and the water vapour pressure is higher in

the building than outside the building there is a tendency for water vapour

to pass from the inside of the building through the permeable foam layer of

the panel and to condense on the cold inside surface of the brick support

panel. As a consequence there is a significant risk of build-up of water at

the interface between the foam insulation layer and the high impact

polystyrene layer (building block support panel) . Since water is not readily

absorbed by extruded closed cell polystyrene foam it tends to accumulate

in the hollow ribs of the building block support panel. As condensation

continues the pressure of water in the hollow ribs increases, and may reach

a level where it begins to force the building block support panel away from

the foam sheet, potentially leading to separation of the two. This is undesirable. Although this problem might be reduced or avoided by using

an absorbent insulating material, any build up of water in the insulating

material would impair its insulating performance. This is also undesirable.

The present invention has been made in consideration of the above

problems.

According to the present invention there is provided a building panel

comprising a permeable sheet of insulating material fastened to an

impermeable sheet of material characterised by one or more conduits

formed in the sheet of insulating material and/or one or more channels

formed in a surface of the impermeable sheet of material adjacent to the

permeable sheet of insulating material arranged to allow fluid to escape from

in between the two sheets of material.

Provision of drainage conduits and/or channels allows any fluid, such

as water, to drain from between the two sheets of material reducing the risk

of delamination of those sheets.

Preferably a plurality of spaced apart channels are formed in a surface

of the permeable sheet of insulating material adjacent to the impermeable

sheet of material. The sheet of insulating material is preferably thicker than

the sheet of impermeable material and accordingly it is more convenient for

channels to be formed in the surface of the insulating material.

In one embodiment a plurality of substantially parallel, substantially

straight, spaced apart channels are formed in a surface of the sheet of insulating material. Preferably at least one of these channels extends to an

edge of the insulating material. More preferably each channel extends to

an edge of the sheet of material and still more preferably each channel

extends between two opposite edges of the sheet of material. In use the

panel is preferably installed so that the channels extend in an upright

direction.

The insulating material preferably comprises a foam material,

particularly an extruded polystyrene foam. The insulating material preferably

resists absorption of water. The impermeable material preferably comprises

a plastics material, for example high impact polystyrene, or a metal, for

example zinc coated steel.

The two sheets of material comprised in the panel are preferably

bonded together with an adhesive. In this case the conduits and/or

channels aid bonding of the two sheets by allowing any air or solvent from

an adhesive trapped between the sheets to escape.

The impermeable sheet preferably defines a plurality of ribs for

supporting building blocks. These ribs may be hollow and preferably extend

generally horizontally in use. Further channels or hollow ribs may extend

between the horizontal ribs to allow for drainage of water.

In order that the invention may be more clearly understood

embodiments thereof will now be described, by way of example, with

reference to the accompanying drawings in which: Figure 1 shows a perspective, part cut away view of a panel according

to the invention;

Figure 2 shows an enlarged cross-sectional view of part of the panel of

Figure 1 ; and

Figure 3 shows an exploded view of an alternative embodiment of a

panel according to the invention.

Referring to Figures 1 and 2 a building block support panel comprises

a permeable closed cell extruded polystyrene insulating foam sheet 10 one

end of which includes a slot 1 1 and the opposite side of which includes a

tongue formation 1 2 which is arranged to fit snugly within the slot of

another panel. This allows large areas to be covered effectively with

multiple panels. The tongue and groove arrangement makes the resulting

structure more stable than a simple butt joint and helps prevent cold

bridging.

An impermeable block support panel 1 3 is formed by vacuum forming

a sheet of high impact polystyrene sheet to produce a series of hollow ribs

14 on the surface of the sheet. The panel 1 3 is bonded to the foam sheet

10 with an SBR adhesive 1 5.

The surface of the foam sheet 1 0 includes a plurality of upright

substantially parallel, substantially straight, generally evenly spaced apart

channels 1 6 each extending between opposite upper and lower edges of the

sheet. The terms 'upright', 'upper' and 'lower' are used in relation to the panel when oriented as illustrated, which is the orientation in which it is

intended to be installed . The channels 1 6 allow any water accumulating

between the foam sheet 10 and block support panel 13 to drain away. This

prevents build up of water pressure between the foam sheet 10 and block

support panel 1 3, particularly in the hollow ribs 14, and thus reduces the

risk of delamination of the block support panel 1 3 and foam sheet 10.

The channels also allow for escape of any air or solvent (from the

adhesive 1 5) that may become trapped between the block support panel 1 3

and foam sheet when the panel is assembled . This is advantageous as any

trapped air or solvent could impair formation of a satisfactory bond between

the sheet 10 and panel 13.

The block support ribs 14 extend laterally across the panel in

substantially parallel and evenly spaced vertical relation to one another. A

margin is provided down each edge of the panel, that is the ribs do not

extend all the way to the edge of the panel. When two panels are joined

there will therefore be a break in the ribs 14 between panels. An additional

break 17 is provided approximately mid-way along each rib. These breaks

1 7 allow any moisture that may become trapped between blocks and the

panel to drain away. Having a gap in the ribs 1 4 between panels helps to

negate the effect of any misalignment between adjacent panels, although

this should preferably be avoided .

The ribs 14 are of hollow and generally triangular cross-section, but with one side being open since they are formed by deforming a single sheet

of material. Each rib 14 has an upper surface 18 for supporting blocks

which extends substantially perpendicularly outwardly from the plane of the

support panel 13. Each rib 14 also has a lower guide surface 1 9 which

extends outwardly and upwardly from the plane of the support panel 13

forming an obtuse angle 20 with the plane. The guide surface 19

strengthens the ribs, acting, to some extent, as a strut.

The spacing of the ribs 14 is greater than the nominal size of the

blocks 21 intended for mounting on the panel. The embodiment illustrated

is designed for use with brick slips of nominal height 65mm. The distance

between the support surface of one rib and the underside of the rib

immediately above is 70mm. The distance between the upper and lower

surfaces of each rib is 1 5mm, therefore the ribs have a pitch of 75mm.

Thus, when using 65mm bricks there will be a standard 10mm mortar bed.

Different brick styles could also be used with different mortar bed sizes.

The surface of the support panel 1 3 other than where there are ribs

is embossed with a relief pattern (not shown) to aid adhesion of blocks.

Any suitable pattern can be used.

The panel may be affixed to another structure using any suitable

technique, for example fasteners may be passed through the panel and into

an underlying structure. Ways in which building block support panels may

be affixed to a surface are well known and will therefore not be described in any further detail.

Building blocks may be affixed to the panel either before, or after, it

has been secured to another structure. First, a suitable adhesive 21 for

example a flexible polyurethane adhesive with good "grabbing" properties

is applied to the surface of the panel between ribs 14. It is preferred that

adhesive is not applied in the region of the drainage gaps 1 7 as this can

impair drainage. Building blocks may then be applied to the adhesive. Figure

2 shows a brick slip 22 bonded to the surface of the block support panel 13

between two ribs 14. When the slip 22 is inserted between the ribs 14 and

pushed home the guide surface on the underside of the upper rib helps to

ensure that the brick slip is moved towards the support surface of the lower

rib.

The spacing of the ribs is such that, when properly seated, there is

some clearance between the top of the brick slip 22 and the next rib. This

allows brick slips which exceed their nominal size to be fitted onto the

support. Were an exceptionally large or incorrectly sized brick slip to be

offered up to the support so that, even when seated on a brick support, the

top of the slip rested on the guide surface 1 9 not only would it be

immediately apparent that the brick slip was oversized but there would be

no risk of the brick becoming wedged between adjacent ribs. This could

potentially damage the panel.

Once brick slips are secured in place with the adhesive 21 the spaces between the bricks can be filled with mortar 23, polymer modified mortar

being preferred, to give the completed panel the appearance of a

conventional brick wall. To ensure good keying of the mortar it is desirable

that the thickness of the brick slip exceeds the height of the ribs 14. When

the ribs 14 are of generally triangular cross-section this provides a better

key for the mortar than, say, a rectangular cross-section.

In an alternative embodiment the block support panel 1 3 is formed

from metal, for example zinc coated steel.

Figure 3 shows an alternative embodiment of a panel comprising a

65mm thick sheet of extruded polystyrene foam 31 of density about

35Kg/m³, sandwiched between two zinc coated 0.7mm thick steel sheets

32. The steel sheets 32 are bonded to the foam sheet 31 with a two-part

polyurethane adhesive. A suitable adhesive is sold by Akzo-Nobel, under

the designation 8243PUR.

The sides of the foam sheet 31 to which the steel sheets 32 are

bonded include a plurality of spaced apart substantially parallel, substantially

straight channels 34 each running between opposite upper and lower edges

of the sheet 31 .

The channels 34 allow any water that accumulates between the steel

32 and foam sheets 31 to drain away, and also any air or solvent trapped

between the foam 31 and steel 32 sheets to escape during assembly of the

panel. A high impact polystyrene vacuum moulded building block support

sheet 35 is bonded to the outside surface of one of the steel sheets 32 with

an adhesive. A similar adhesive as used to bond the steel sheets 32 to the

foam sheet 31 is suitable. Prior to bonding the building block support sheet

35 to the metal sheet 31 the building block support sheet is preferably

corona arc discharge treated . This results in better adhesion to the metal

sheet 31 .

The building block support 35 comprises a sheet having a series of

substantially parallel evenly spaced apart projecting ledges 36 extending

laterally across its surface, but not all the way to the lateral edges of the

sheet. As such, when two panels are placed adjacent to each other there

is an upright gap in the ledges between the panels. One or more additional

gaps 37 are provided along the length of each ledge to allow any trapped

moisture to drain away. Having a gap in the ledges between panels helps

to negate the effect of any misalignment between panels, although this is

preferably avoided . The ledges themselves are provided by ribs of

substantially triangular cross-section, but with one side open as they are

formed by deforming a single sheet of material. Each rib has an upper

surface for supporting building blocks which extends substantially

perpendicularly outwardly from the plane of the sheet 35. The exposed

surface of the sheet, other than where there are blocks, includes a relief

pattern (not shown) to aid adhesion of building blocks thereto. In use 20mm thick brick slips are supported on the ledges of the

building block support sheet 35, and bonded to the building block support

with an adhesive.

In an alternative embodiment the steel sheet 32 remote from the

block support panel is deleted.

The above described embodiments exhibit a considerably reduced risk

of delamination due to accumulation of water compared to prior panels.

The above embodiments are described by way of example only.

Many variations are possible without departing from the invention.

Claims

1 . A building panel comprising a permeable sheet of insulating material

fastened to an impermeable sheet of material characterised by one or

more conduits formed in the sheet of insulating material and/or one

or more channels formed in a surface of the impermeable sheet of

material adjacent to the permeable sheet of insulating material

arranged to allow fluid to escape from in between the two sheets of

material.

2. A panel as claimed in claim 1 , wherein a plurality of spaced apart

channels are formed in a surface of the permeable sheet of insulating

material adjacent to the impermeable sheet of material.

3. A panel as claimed in claim 2, wherein the channels formed in the

permeable sheet of insulating material are substantially parallel.

4. A panel as claimed in any of claims 1 to 3, wherein at least one

channel formed in the surface of either sheet of material extends to

at least one edge of that sheet.

5. A panel as claimed in any preceding claim, wherein the permeable

material comprises a foam material.

6. A panel as claimed in any preceding claim, wherein the impermeable

material comprises a plastics material or a metal.

7. A panel as claimed in any preceding claim, wherein two sheets of

material are bonded together with an adhesive.

8. A panel as claimed in any preceding claim, wherein the sheet of

impermeable material defines a plurality of ribs for supporting building

blocks.

9. An installation comprising a panel as claimed in either claim 1 or 2 or

any of claims 3 to 8 when appendant to either claim 1 or 2, wherein

at least one channel in either the impermeable or permeable sheet

extends in an upright direction.