CA2096296C - Insulating cladding panel - Google Patents

Abstract

An insulating cladding panel for an exterior wall of a building is a sheet of insulating material having a plurality of intersecting channels on its interior surface. The channels are sized and spaced to provide a rapid equalization of pressure across the panel when installed on the wall. This pressure equalization essentially eliminates the forces promoting water penetration through the panel joints to the wall. The channels also facilitate the escape of any water which may penetrate the panel system. The neutralization of the live wind load by the channel system of the panels eliminates the need for supporting members when installing the panels on a wall.

Description

-1- 20~6296 The invention is an insulating cladding panel for an exterior wall of a building. Operating on the rainscreen principle, the panel greatly reduces water penetration of a vertical wall assembly by promoting the equalization of pressure across the panel to the wall.

There are three main factors necessary for water penetration of a vertical exterior wall of a building:

(1) water at the surface of the wall;

(2) openings through which the water can pass; and (3) a force to drive the water through the openings.

Elimination of any of these factors should significantly reduce water penetration.

Because of the impracticality and expense involved in completely sealing all openings or shielding an exterior wall from water, many of the known methods for preventing water penetration rely on principles other than the elimination of the above factors. One method commonly used in the prior art is to provide a cavity behind the exterior face of a wall through which water is directed downward by gravity and drained to the exterior of the wall. Often the cavity will extend to an opening at the top of the wall to allow water vapour to escape.

Such a cavity may comprise vertical channels or grooves provided in a moisture impermeable layer of sheathing underlying the exterior surface of a wall assembly. Although these channels serve to drain away moisture which would otherwise damage the inside of the wall, they do not reduce the forces which drive water into the wall. Accordingly, there remains considerable potential for damage to the interior of the wall due to the quantity of water penetrating the exterior surface and the residence time of such water within the wall assembly. Ideally, the interior air spaces of a wall assembly should receive a minimal amount of water through condensation or wall penetration, and such water should be removed as quickly as possible.

Summary of the Invention The present invention provides a rigid, water impermeable sheet of insulating material for a wall, the sheet having a system of interconnected channels extending to the top and bottom of the wall, thereby giving the sheet drainage capabilities similar to grooved wall sheathing disclosed in the prior art.

The panels of the invention differ from prior structures in that their channels are of sufficient size and frequency to allow rapid pressure equalization between the interior of a wall assembly and the exterior panel surfaces. A pressure differential across a panel attached to a wall, caused by a gusting wind for example, produces a highly variable force which drives or draws water through holes or gaps in the exterior cladding surface. The rapid pressure equalization function of the present invention overcomes the deficiencies of prior structures by significantly reducing this force, and thus, reducing the amount of water penetrating the panels to the wall of the building.

The reduction in the pressure differential across the wall assembly also has the beneficial effect of reducing the live load on the wall, thus obviating the need to provide support members for the structurally weak insulating material of the panel. This feature has the benefit of making the insulating panel of the invention ~Q96296 cheaper and easier to install than panels in current use.

Thus, according to the present invention there is provided an insulating cladding panel for an exterior wall of a building, comprising a sheet of insulating material having an interior side with a plurality of intersecting channels oriented to communicate with ch~nnels of adjacent panels installed on the wall. The channels are of sufficient depth, width and frequency so that when installed, they allow rapid pressure equalization across the sheet from the exterior side to the wall of the building. The channels of the sheet facilitate the escape of moisture which may penetrate the installed panels. The panels of the invention have an outer architectural covering which is attached to the insulating sheet usually after the sheets are installed on the wall.

Brief Description of the Drawings Figure 1 is a perspective view of a portion of a panel of the present invention showing a channel pattern on the interior side of the insulating sheet.

Figure 2 is a plan view of a wall assembly incorporating panels of the invention.

An insulating cladding panel 10 comprises a sheet 11 of insulating material and an architectural outer material 12 such as an architectural coating usually applied to the sheets 11, for example, by spraying, after they have been installed on a wall 15. The insulating sheet 11 is a water impermeable rigid material, preferably a lightweight plastic foam. The skilled person will appreciate that a wide variety of insulating materials may be suitably used for the sheet 11, such as, polystyrene foam or mineral wool board.

_4_ 209~29~

The interior side 17 of the sheet 11 is provided with a system of intersecting channels 19. The chAnnels 19 are oriented to communicate with channelæ 19 of adjacent panels 10 when installed on the wall 15.
Accordingly, a regular checkerboard pattern of chAnnels 19 is preferred for the interior side 17 of the sheet 11.
The channels 19 are preferably V-shaped, each having a depth preferably of 1.0 to 1.5 cm. and a width at the sheet surface 17 of about 2 cm. A spacing of parallel channels on the order of 10 cm. is preferred. The skilled person will appreciate that the size and configuration of the intersecting channels 19 may vary considerably within the scope of the invention. The important feature served by the channels 19 is the provision of rapid pressure equalization across the panel 10 .

It is also preferable to provide the sheet 11 with bevelled edges 21. The edges 21 cooperate when installed on the wall 15 to create additional channels 19. The creation of such channels 19 at the joints between panels 10 provide a direct and extensive access to the channel system for air penetrating the joints. This feature allows for the inevitable failure of joint sealers used at the time of installation of the panels 10. Thus, the Z5 integrity of the wall assembly will not depend on the sealing system used in its construction, since water penetration is minimized by the dynamic principles for pressure equalization provided by the structure of the panel 10 of the invention.

Because of the pressure equalizing properties of the panel 10, the wind loads to which wall panels are normally subjected are effectively neutralized, thereby removing the need to employ structural supports like furring or reinforcing sheet material. As shown in Fig.
2, the sheets 11 are attached to the wall 15 using a thin adhesive layer 23 and preferably mechanical fasteners (not shown). After the sheets 11 are installed on the wall 15, the exterior surfaces of the sheets 11 are finished by applying a conventional architectural coating or other suitable exterior finishing material. Of course, the invention includes those panels 10 wherein the exterior finishing material is applied prior to installation of the panel 10 on the wall 15.

Clearly, the invention may be used in a variety of exterior wall assemblies incorporating vapor barriers and other elements not specifically referred to in this description which is not intended to in any way limit the scope of the invention as defined by the following claims.

Claims (7)

1. An above ground wall assembly for a building, comprising:
an upright wall having a top, a bottom, and interior and exterior sides;
a plurality of sheets of water impermeable insulating material attached in edge to edge relation to the exterior side of the wall, each sheet of insulating material having an exterior side and an interior side, the interior side facing the wall and having bevelled edges and a plurality of intersecting channels extending to said edges, said channels being of sufficient depth, width and frequency so that they allow rapid air pressure equalization across the sheets attached to the wall from the exterior side of the sheets to the wall of the building, and so that the escape of any moisture penetrating the sheets to the wall is facilitated; and an architectural outer finishing material attached to the exterior side of each sheet of insulating material.

2. A wall assembly as claimed in claim 1, wherein the intersecting channels form a checkerboard pattern.

3. A wall assembly as claimed in claim 1, wherein the channels are V-shaped and about one centimetre deep and about two centimetres wide.

4. A wall assembly as claimed in claim 3, wherein the channels are about 1.5 cm deep.

5. A wall assembly as claimed in claim 2, wherein parallel channels are spaced about 10 cm. apart.

6. A wall assembly as claimed in claim 1, wherein each sheet is a polymeric foam material.

7. A wall assembly as claimed in claim 1, wherein the outer finishing material is an architectural coating.