Moisture control strip

A wall is provided comprising an inner wall component, an outer wall component, and a plurality of the moisture control strips described above, disposed between the inner wall component and the outer wall component. The projections on the first wall component contacting face engage one of the inner wall component and the outer wall component. The second wall component contacting face engages the other of the inner wall component and the outer wall component. The moisture control strips are horizontally spaced from each other within the wall.

FIELD OF THE INVENTION

The present invention relates to the control of moisture within walls, and more particularly to a moisture control strip for use in wall construction.

BACKGROUND OF THE INVENTION

Structural walls for buildings such as residential, commercial, or industrial buildings, are often constructed in layers. Typically, a wall sits on a foundation, and includes a backup wall having a floor plate and a ceiling plate and a set of vertical studs. Usually, sheathing (which may be plywood, oriented strand board, or the like) is disposed on the outside face (i.e. the face that faces towards the outside of the building) of the backup wall. The sheathing is covered by a moisture barrier membrane. A metal flashing is disposed at the bottom of the wall, above the foundation and between the sheathing and the membrane.

On the outside of the membrane, a layer of thermal insulation is typically installed. In some cases, moisture control panels, such as that described in published Canadian Patent Application 2,249,509 and owned by the applicant herein, are disposed outside of the insulation. Fasteners are installed through the moisture control panel, the insulation, the membrane, the sheathing and into the vertical stud to hold the moisture control panel and insulation in place within the wall. A wire mesh supporting a layer of stucco is disposed on the outside of the moisture control panel, with the mesh also being held in place by the fastener.

SUMMARY OF THE INVENTION

In a first aspect, the invention is directed to a moisture control strip including an elongate member having first and second wall component contacting faces. The second wall component contacting face is opposed to the first wall component contacting face. The member has a width across the first and second wall component contacting faces. The first wall component interface side has a plurality of projections defined thereon. The projections are spaced vertically from each other.

In a second aspect, the invention is directed to a wall comprising an inner wall component, an outer wall component, and a plurality of the moisture control strips described above, disposed between the inner wall component and the outer wall component. The projections on the first wall component contacting face engage one of the inner wall component and the outer wall component. The second wall component contacting face engages the other of the inner wall component and the outer wall component. The moisture control strips are horizontally spaced from each other within the wall.

In a third aspect, the invention is directed to a method of making a moisture control strip, comprising:(a) providing a longitudinally extending member having a generally rectangular cross-sectional shape; and(b) forming a plurality of laterally extending grooves across the entire width of the member, wherein the grooves are spaced longitudinally from each other, and wherein the grooves are defined at least in part by an upper face and a lower face, and wherein the upper and lower faces extend at a downward slope angle in a direction into the member.

DETAILED DESCRIPTION OF THE INVENTION

Now referring toFIGS. 1 and 2, a moisture control strip according to the present invention is shown generally at10. The moisture control strip10comprises an elongate member12having a length L in a longitudinal direction which may be substantially greater than its width W (seeFIG. 2), and substantially greater than its thickness T.

The elongate member12has first and second substantially oppositely facing wall component contacting faces14and16, respectively, and two side faces20extending therebetween. The first wall component interface side14has a plurality of spaced projections18may be defined thereon, while the second wall component contacting face16may be generally planar.

Each projection18has a wall component contacting surface24thereon for contacting a wall component adjacent the moisture control strip (see,FIG. 4).

Each projection18may extend across the entire width W of the strip10, and is spaced from any adjacent projections18by a laterally extending groove22. The groove22has an upper face28, a lower face30and an inner face31. The upper face28extends downwards in a direction inwards from the wall component contacting surface24of the projection18above the groove22. The lower face30extends downwards in a direction inwards from the wall component contacting surface24of the projection18below the groove. The inner face31may be generally parallel to the wall component contacting surfaces24. A trough33is formed at the intersection of the lower face30and the inner face31. The trough33is open at both ends.

When the projections18contact a wall component, the upper and lower faces28and30both are configured by their slope angle, to convey into the trough33droplets of moisture that they catch running down the wall component. The droplets of moisture may form on the wall component, for example, as a result of condensation. Moisture collected in the trough33eventually can be drained off at the two open ends of the trough33, down the side faces20of the moisture control strip10.

Further, because the groove22is open at both ends, it provides airflow and aeration to the wall component against which the projection18is abutted, facilitating drying of the wall component, relative to a strip or panel in which no grooves were present that permitted aeration.

Prior to machining the grooves22, the moisture control strip10may initially be a longitudinally extending member having a rectangular (eg. square) cross-sectional shape. Each groove22may be machined in a single pass in the moisture control strip10, by moving an appropriately configured cutting tool (not shown) across the width of the first wall component contacting face14, which is, in the embodiment shown in the Figures, is the width W of the strip10. By having the projections extend across the entire width W of the first wall component contacting face14simplifies the machining required to form the projections18ie. so that machining across the width of the first wall component contacting face14is sufficient to form the projections18, which in turn reduces the cost of manufacture for the moisture control strips10. It will be noted that the grooves22may be formed by any other suitable means instead of machining.

A vertical groove26(seeFIG. 2) may extend downwards along the height of each wall component contacting face24. Thus, when the projections18contact a wall component, the groove26remains open to air at both ends. In similar fashion to the groove22, the groove26also facilitates aerating and thus drying of the surface of the wall component where it is in contact with the wall component contacting face24, if the wall component becomes wet in this contact region.

Referring toFIG. 3, the moisture control strip10may further include a series of recesses34and apertures32on the second wall component contacting face16. The recesses34function to collect moisture from the wall component contacted by the face16. At the bottom of each recess34, an aperture32extends therefrom downwards through the moisture control strip10to a trough33on the opposing face14. The aperture32conveys away moisture collected in the recess34down to the trough33, where the moisture can then be drained off down the side faces20.

With reference toFIGS. 4 and 5, a moisture control strip10according to the present invention is shown installed in a wall.FIG. 4shows the moisture control strip10installed in a first orientation, andFIG. 5shows the moisture control strip10installed in a second orientation. The wall is shown generally at200, and comprises an inner wall component202, and an outer wall component204, with a plurality of moisture control strips10disposed between the inner wall component202and the outer wall component204.

The wall200sits on a foundation212, and includes a backup wall214, which has a floor plate216and a ceiling plate (not shown) and a set of vertical studs218. One such vertical stud218is shown. Sheathing220, which may be made of plywood, oriented strand board or some other suitable material, is disposed on the outside face of the backup wall214. A moisture barrier membrane222covers the sheathing220. A metal flashing224is disposed at the bottom of the wall10, between the sheathing220and the membrane222and above the foundation212. A layer of thermal insulation226is installed on the outside of the membrane222. The layer of insulation226may be rigid insulation, or alternatively, it may comprise batt or other non-rigid insulation sheathed with a wood panel sheathing on its outside face. Thus, the inner wall component202comprises the vertical studs218, the sheathing220, the membrane222and the layer of thermal insulation226. The layer of thermal insulation226, which may be rigid, comprises the outer surface of the inner wall component202. Alternatively, if no thermal insulation were installed, the membrane222would comprise the outer surface of the inner wall component202. The outer wall component204comprises wire mesh234having a layer of stucco236supported thereon. As will be appreciated by one skilled in the art, the layer of stucco236is somewhat moisture previous. As can be seen, the moisture control strips10are oriented such that their longitudinal direction (in which their length L is measured) corresponds to a vertical axis AV of the wall200. The wall components, including the moisture control strips10, are held together by fasteners232.

The moisture control strips10may be positioned in the wall200with the first wall component contacting face14facing the inner wall component204, as shown inFIG. 4. In the orientation shown inFIG. 4, the first wall component contacting face14faces the layer of insulation226, and the second wall component contacting face16faces the mesh wire234and stucco236. In the orientation shown inFIG. 5, the first wall component contacting face14faces the outer wall component204, which may include, for example, the wire mesh234and the layer of stucco236, and the second wall component contacting face16faces the insulation226.

Referring toFIG. 6, when the moisture control strips10are positioned in the orientations shown inFIG. 4, the moisture control strips10may be positioned horizontally spaced from one another by a distance R, so that an airspace238is defined between pairs of adjacent strips10. The width of the airspace238(ie. the distance R) between adjacent strips10may be selected based on a number of factors including, for example, the size and strength of the mesh wire234(FIG. 4) that is positioned thereon for supporting the layer of stucco236.FIG. 7shows a similar arrangement of horizontally spaced strips10in the orientation shown inFIG. 5.

In the airspaces238, ie. the regions between the moisture control strips10, any moisture buildup on the layer of stucco236or on the layer of insulation226can drain downwards along the stucco layer236onto the flashing224and out. Referring toFIG. 4, where each strip10contacts the layer of stucco236, moisture in the stucco236can be collected in the recesses34and conveyed away through the apertures32, as described above.

Using a plurality of moisture control strips10that are spaced apart by a selected distance R from one another provides several advantages over using a moisture control panel such as that shown in Canadian patent application 2,249,509. One advantage is that the cost of the moisture control strips10is substantially lower than that of the aforementioned panel. This is because the strip consumes less base material, and requires substantially less machining.

Another advantage is that the spaced strips10create fewer heat conduction paths though the wall200than are created by a large, wide panel. In other words, the overall heat loss through the wall200is lower using the moisture control strips10than using a panel.

It is contemplated that the orientation of the moisture control strip10will be selected based on which of the inner and outer wall components202and204is more likely to build up moisture. For example, with respect to condensation of water vapour in the air between the inner and outer components202and204, the wall component that receives more condensation will depend at least in part on the ambient temperatures expected on both sides of the wall200. Also, moisture buildup can occur in one or both of the inner and outer wall components202and204as a result of such factors as damp weather conditions outside and humidity conditions inside. These and other considerations will influence which orientation best serves the function of the moisture control panel10.

In similar fashion to the configuration shown inFIG. 4, in the airspaces, ie. the regions between the moisture control strips10in the orientation shown inFIG. 5moisture buildup on the layer of stucco236and on the layer of insulation226can drain downwards along the insulation layer236onto the flashing224and out. Where each strip10contacts the layer of insulation226, moisture running down the layer of insulation226can be collected in the recesses34if they are provided, and conveyed away through the apertures32if they are provided, as described above.

In the embodiments described above, the grooves22extend strictly laterally across the width of the first wall component contacting face14. It is alternatively possible for the grooves22to extend laterally across the width of the first wall component contacting face14, but at an angle with respect to a lateral axis AL (FIGS. 6 and 7), so that the grooves22promote the drainage of moisture on a particular side of the moisture control strip10. As another alternative, the grooves22may be generally chevron shaped, while still extending across the width of the first wall component contacting face14. In this case, the apex of the chevron would be higher than the ends of the chevron, so that moisture is promoted to be drained off both ends of the groove.

The grooves22have been described as being configured to convey moisture away from the surface with which they are in contact (eg. the inner or outer wall components). It is alternatively possible for the grooves22to principally provide aeration to the surface with which it is in contact, instead of providing a drainage function. Accordingly, the grooves22may have upper and lower faces that are generally perpendicular to the plane of the wall component contacted by the first wall component contacting face14.

It will be appreciated by a person skilled in the art the inner and outer wall components with which the moisture control strip10can be used are not limited to those shown in the Figures.

It will be appreciated by one skilled in the art that numerous variations and modifications may be made to the embodiments described above without departing from the scope of the present invention, and all such variations and modifications are intended to be encompassed within the scope of the present invention as defined by the appended claims.