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TECHNICAL FIELD  
       [0001]     This invention relates to moisture drainage products and, more particularly, to moisture drainage products intended for incorporation in wall systems and methods for providing moisture drainage in wall systems.  
       BACKGROUND  
       [0002]     Warm, moisture-laden air can exist in buildings including buildings in colder climates. A significant amount of moisture can be placed into the air through common household activities, such as cooking, bathing and showering.  
         [0003]     Especially in colder climates, insulation in a wall structure helps to reduce heat loss from buildings which are heated due to the cold climate. As moisture-laden air passes through the wall structure of such buildings, the moisture-laden air encounters steadily decreasing temperatures. As the air is cooled while moving from the interior of a wall structure to the exterior of the wall structure, the air can eventually reach its dew point and water vapor in the air condenses to form moisture. The result can be a moisture buildup in the wall structure.  
         [0004]     Vapor barriers are commonly employed on the warm side of wall structures in order to prevent moisture-laden air from entering the wall structure. However, vapor barriers are not usually perfect. In a typical building, multiple penetrations of a vapor barrier can occur, e.g., from electrical and plumbing lines and from window and door openings.  
         [0005]     If the exterior temperature is cold enough, moisture existing in the wall structure could eventually turn to frost or ice and, thus, be prevented from draining from the wall structure, at least until the exterior temperature increases. When that happens, however, the moisture can still cause significant damage to the wall structure.  
         [0006]     Various products have been created to allow drainage of moisture from wall structures once the moisture has formed in the wall structure.  
         [0007]     U.S. Pat. No. 3,654,765, Healy et al, Subterranean Wall Drain, discloses a subterranean wall drain unit including a drain pipe having openings therein and a longitudinally extending planar core defining channels normal to the pipe. A water pervious sheet material covers one face of the core and the openings in the pipe to form a filter therefore. The other face of the core may be covered with a plastic sheet or other vapor barrier.  
         [0008]     U.S. Pat. No. 3,888,087, Bergsland, Foundation Wall Protective Sheet, discloses improvements in protective membranes or sheets for foundation walls. The sheets have regular courses of protrusions for spacing the sheet from the foundation wall and a porous backing for drainage outwardly of the sheet. The protrusions provide air channels between the protective sheet and the foundation for thermal insulation and for facilitating drying of the foundation wall. Small vertical ribs between the courses of the protrusions provide convenient water passages to take care of drainage water in the porous backing without interfering with the air spaces and incidentally providing bending vertical lines for more facile installation handling. Modifications of the sheet include transverse ribs at lower portions of the sheet to allow horizontal bending thereof wall for footing and drainage configurations. A barrier for preventing back fill falling between the protective sheathing and foundation is also disclosed.  
         [0009]     U.S. Pat. No. 3,318,056, Thompson, Ventilating Wall Construction With Stud Location Indicators, discloses a sheet of building material placed between wall veneers for moisture protection that includes vertical drainage channels and perforations.  
         [0010]     U.S. Pat. No. 6,298,620, Hatzinilolas, Moisture Control Panel, discloses a moisture control panel used in exterior walls. A wall constructed with the panel has an inner back-up wall component and an outer wall component of a moisture pervious material, for example, stucco. The moisture control panel is positioned between the two. It has a base sheet on the inner face of the outer wall component. A set of drying perforations slope downwardly toward the inside through this sheet. This drains moisture from the inside of the outer wall component. On the inside, the base sheet has a set of upwardly sloping bosses which provide an air space on the inside the moisture control panel providing for air circulation and drainage of any moisture.  
         [0011]     U.S. Pat. No. 4,381,630, Koester, Foundation Vent Structure, discloses a foundation vent structure positioned upon the footings of the building below the lowermost row of concrete blocks of the basement wall and extends below the concrete floor of the basement. The vent structure is formed of a plastic material, preferably in strips, and is shaped to define alternate tunnels and channels having openings therein. The vent structure intercommunicates the openings in the hollow, concrete blocks with the drain area located along the marginal area below the basement wall to permit moisture to be vented into this drain area.  
         [0012]     However, these products encounter a problem when the wall structure is interrupted by a horizontal structural member such as a wall opening, e.g., a window or door opening, or a shelf angle typically placed at building floor levels or upon a certain vertical distance. Such interruptions disrupt the otherwise downward flow of moisture to the bottom of the wall structure and may interfere with the proper operation of some of the above solutions. Such products are not typically designed to operate effectively at a head joint where the wall structure is interrupted by a wall opening or shelf angle.  
       SUMMARY OF THE INVENTION  
       [0013]     This problem is exacerbated when the exterior veneer of the wall structure is formed with modular building products, such as brick. Mortar is typically used to form a mortar joint between otherwise adjacent bricks and between layers of bricks. Such mortar can interfere with the proper flow of moisture wall through the wall cavity and, ultimately, outside of the wall cavity. When mortar is used to set bricks, for example, on a steel lintel or shelf angle, the mortar can effectively hinder the passage of moisture from the wall cavity to the exterior of the wall structure. Such horizontal interruption is collectively referred to herein as a horizontal interruption.  
         [0014]     The present invention is a wall structure, method and a head joint drainage device which allows a channel for moisture which otherwise might collect in a wall structure where a head joint encounters a horizontal interruption to properly escape to the exterior of the wall structure.  
         [0015]     In one embodiment, the present invention provides a head joint drainage device adapted to allow drainage of moisture from a head joint meeting a horizontal interruption of a structure formed with a plurality of building products set with mortar forming a mortar joint between adjacent ones of the plurality of modular building products. A spacer has a top portion, having a length approximately equal to a depth of the plurality of building products and a width approximately equal to a width of the mortar joint, adapted to block the mortar from reaching the horizontal interruption and has a side portion adapted to keep the portion a distance away from the horizontal interruption, the distance allowing moisture drainage from the head joint.  
         [0016]     In another embodiment, the present invention provides a wall system for a structure having a head joint meeting a horizontal interruption in a wall of a structure, the wall having a veneer. An angle is positioned at the head joint. A plurality of modular building products are set on the angle forming the veneer. Mortar is set between the adjacent ones of the plurality of modular building products forming a head joint of mortar. A spacer is positioned on the angle between the adjacent ones of the plurality of modular building products, the spacer forming a moisture drainage channel between the adjacent ones of the plurality of modular building products between the mortar and the angle.  
         [0017]     In another embodiment, the present invention provides a method of providing drainage of moisture from a head joint meeting a horizontal interruption of a wall of a structure, the wall having a veneer constructed from a plurality of modular building products set with mortar forming a mortar joint between adjacent ones of the plurality of modular building products. One of the plurality of modular building products is placed on an angle at the horizontal interruption. A spacer is set on the angle adjacent the one of the plurality of modular building products. The mortar is applied to the one of the plurality of modular building products forming the mortar joint. Another of the plurality of modular building products is placed on the angle adjacent to the spacer.  
         [0018]     In a preferred embodiment, the plurality of modular building products comprise a plurality of bricks.  
         [0019]     In a preferred embodiment, the spacer has a top portion, having a length approximately equal to a depth of the plurality of building products and a width approximately equal to a width of the mortar head joint, adapted to block the mortar from reaching the angle and has a side portion adapted to keep the portion a distance away from the angle, the distance allowing moisture drainage from the head joint.  
         [0020]     In a preferred embodiment, the top portion of the spacer is solid.  
         [0021]     In a preferred embodiment, the side portion of the spacer is angled back from a front edge of the spacer.  
         [0022]     In a preferred embodiment, the spacer further comprises a second one of the side portion.  
         [0023]     In a preferred embodiment, the side portion of the spacer and the second one of the spacer each have approximately equal heights.  
         [0024]     In a preferred embodiment, the spacer is formed into a plurality of sections, each of the plurality of sections having a length selected so that a length of an integral number of the plurality of sections is approximately equal to the depth of the plurality of modular building materials.  
         [0025]     In a preferred embodiment, the top portion of the spacer has a transverse groove providing an ability for the plurality of sections to snap apart by hand.  
         [0026]     In a preferred embodiment, the side portion of the spacer angles back from the top portion the transverse groove.  
         [0027]     In a preferred embodiment, the side portion of the spacer roughly forms a v-shape.  
         [0028]     In a preferred embodiment, the spacer is of a color which approximates a color of the mortar. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0029]      FIG. 1  is a front elevation of wall system utilizing an embodiment of the present invention;  
         [0030]      FIG. 2  is a perspective view of a partially constructed wall system in accordance with an embodiment of the present invention;  
         [0031]      FIG. 3  is a close-up perspective view of a spacer in accordance with an embodiment of the present invention;  
         [0032]      FIG. 4  is another view perspective view of the spacer of  FIG. 3 ;  
         [0033]      FIG. 5  is a front view of a detail of a wall system in accordance with an embodiment of the present invention;  
         [0034]      FIG. 6  is a front view of a wall system incorporating the head joint drainage device of the present invention;  
         [0035]      FIG. 7  is a perspective view a strip of spacer elements;  
         [0036]      FIG. 8  illustrates a head joint of a wall system in preparation for the installation of the present invention;  
         [0037]      FIG. 9  illustrates the removal of one or spacer elements from a strip of spacer elements;  
         [0038]      FIG. 10  illustrates the placement of a spacer at the head joint of a wall system;  
         [0039]      FIG. 11  is a side view of a spacer placed next to a modular building product at the head joint of a wall system;  
         [0040]      FIG. 12  is a front view of two spacers installed between two modular building products;  
         [0041]      FIG. 13  illustrates the spreading of a bed of mortar over a row of modular building products;  
         [0042]      FIG. 14  illustrates tuck pointing of mortar between modular building products; and  
         [0043]      FIG. 15  illustrates of a front view of an installed head joint drainage device and wall system using a head joint drainage device showing the weep holes created. 
     
    
     DETAILED DESCRIPTION  
       [0044]     A head joint is formed in a wall structure when the wall structure has an opening in what would otherwise be an unbroken expanse of wall. Openings are commonly made in wall structures for windows and doors, for example. The wall structure essentially stops at the top of the window or door opening and, in the case of a window opening, may start again below the opening. The wall structure above the opening is typically supported by a structural header, designed to carry the load of the wall structure above the opening and spread the weight of that load the load bearing capacity of the wall structure on either side of the opening.  
         [0045]     In the case of a wall structure having an a brick exterior, typically an exterior veneer of brick set in mortar, the weight of the wall structure above an opening is also distributed by a structural member to either side of the opening. With a brick wall structure, the load bearing member is typically called a lintel. A lintel is commonly constructed of a piece of steel, or other material capable of transferring weight. The lintel allows the weight of bricks placed on the lintel to be transferred to other structural wall members on either side of the opening. Typically, a lintel is fashioned from an “L-shaped” steel member, or angle iron, which is fastened to structural wall elements either behind the lintel or below the lintel but on either side of the opening.  
         [0046]     Further, a wall structure may have a shelf angle installed periodically or as needed at certain points or a certain vertical distances. Typically, a shelf angle can be installed at every building floor or perhaps for every sixteen (16) feet of vertical rise. A shelf angle performs a similar function as a lintel performs above an opening in the wall structure. A shelf angle is secured to a structural member and then bears the load of bricks, or other modular building components, placed above the shelf angle. A shelf angle can be fashioned from the same or similar members as a lintel as described above. A “head joint” is also formed between adjacent building components at the top of each shelf angle.  
         [0047]     Either a lintel or a shelf angle creates a horizontal interruption in the otherwise uninterrupted wall structure of the exterior veneer. For purposes of this application, the term “angle” is used to describe both the lintel, as typically used above openings in wall structures, such as windows and doors, and the shelf angle, as typically used in periodic vertical increments in otherwise uninterrupted wall structures. References hereinafter referring to a lintel apply equally well to a shelf angle. For purposes of this application, discussion related to draining of moisture, or related activity, from head joints refers to both head joints occurring at lintels and to similar joints occurring at shelf angles.  
         [0048]      FIG. 1  is a front elevation view of a building  2  having wall system  10  constructed in accordance with an embodiment of the present invention. Building  2  has a door opening  4  and four window openings  22 . At the top edge of door opening  4  and each window opening  22 , lintel  24  provides structural support for bricks  20 . Lintels  24  are used at horizontal interruptions in wall system  10  created by door opening  4  and window openings  22 . Additionally, shelf angles  6  are placed in periodic vertical distances on wall system  10 . Shelf angles  6  also provide structural support for bricks  20 .  
         [0049]      FIG. 2  illustrates a partially constructed brick veneer wall system  10  utilizing an embodiment of the present invention. Wall system  10  is constructed from a structural wall  12 , in this case using commonly available concrete blocks  14 . Structural wall  12  may be reinforced with reinforcing rods  16 . An exterior veneer wall  18  is constructed on the exterior side of structural wall  12 . Veneer wall  18  is constructed conventionally from modular building products, such as bricks  20 .  
         [0050]     Window opening  22  is formed into wall system  10 . Lintel  24  is placed at the top edge of window opening  22  and secured to structural wall  12 . Drip plate  26  can be placed directly on top of lintel  24  as an aid in preventing moisture from draining back along the underside of lintel  24  into wall structure  10 . “Z-shaped” flashing  28  is then placed above lintel  24  and drip plate  26  to direct moisture which may exist in wall structure  10  to the exterior of wall structure  10  to prevent that moisture from entering window opening  22 . Veneer wall  18  can then continue to be constructed above window opening  22  with lintel  24  supporting the weight of bricks  20 .  
         [0051]     As bricks  20  are laid in the construction of veneer wall  18 , mortar  30  is placed between adjacent bricks  20 , both vertically and horizontally. While flashing  28  is designed to direct moisture which may exist in wall structure of above window opening  22  to the exterior; it has been found that mortar  30  may inhibit that function. Mortar  30  may mostly or completely fill the space between bricks  20  and leave little of no room for moisture otherwise directed by flashing  28  to escape to the exterior of wall system  10 .  
         [0052]     Spacer  32  is placed between horizontally adjacent bricks  20  on top of flashing  28  to provide prevent mortar  30  from completely filling the space between adjacent bricks  20  and creating a channel allowing moisture from wall system  10  to be properly directed to the exterior by flashing  28 .  
         [0053]     Spacer  32  is more clearly illustrated in  FIG. 3  and  FIG. 4 . In a preferred embodiment, spacer  32  has a solid top surface  34  intended to substantially block mortar  30  from occupying the space created below top surface  34 . Top surface  34  is approximately ⅜ inch (0.95 centimeters) wide. Side edges  36  provide support for top surface  34  to be spaced away from flashing  28  and provide space for drainage. Sides edges  36  have a height of approximately ⅜ inch (0.95 centimeters) high. Top surface  34  has a front edge  38  intended to flush with, or nearly flush with, the front edge of mortar  30  between bricks  20 . The length of spacer  32  preferably is approximately to the depth of mortar  30  placed between adjacent bricks  20 . The width of top surface  34  of spacer  32  is approximately equal to the width of mortar  30  forming a mortar joint between adjacent bricks  20 . Spacer  32  will preferably fill the width of the mortar  30  joint between tow adjacent bricks  20 . The height of side walls  36  of spacer  32  is enough to allow moisture to drain through a channel formed by the underside of top surface  34  and the interior of side edges  36 . Preferably, the height of side walls  36  is approximately equal to the width of top surface  34 .  
         [0054]      FIG. 5  is a close-up frontal view of spacer  32  installed as a head joint weep in wall system  10  above window opening  22 . Bricks  20  are set side by side on lintel  24  with mortar  30  forming a mortar joint between bricks  20 . Mortar  30  also forms a mortar joint between side by side bricks  20  and brick  20  set above the side by side bricks. Spacer  32  is installed between bricks  20  with the bottom of side edges  36  resting on flashing  38  just above lintel  24 . Mortar  30  is preventing from filling the entire joint between bricks  20  by top surface  34  of spacer  32  creating a weep hole  40  below top surface  34  and between side edges  36 .  
         [0055]     Wall system  10  seen from the front in  FIG. 5  shows that front edge  38  of top surface  34  of spacer  32  is visible. The visibility of spacer  32  can be diminished by matching the color of front edge  38  of spacer  32  with the color of mortar  30 . Spacer  30  then blends in with mortar  30  and, hence, is less visible.  
         [0056]     Side edges  36  are angled, or tapered, away from front edge  38  of top surface  34 . Such tapering or angling provides several advantageous benefits. One benefit is that side edges  36  are not as visible a front exterior view of wall system helping to diminish the visibility of spacer  32 . Further, tapering or angling of side edges  36  at the rear of spacer  32  helps to ensure that any moisture located toward the rear of veneer wall  18  above flashing  28  enter weep hole  40  and be transported to the exterior of wall system  10 . In a preferred embodiment, side edges  36  of spacer  32  are angled back from top surface  34  at both ends of spacer  32  allowing spacer  32  to be installed in either front to back orientation.  
         [0057]      FIG. 6  shows a complete window opening  22  in wall system  10 . Spacers  32  are shown installed at five locations along header joint formed by lintel  24 . A spacer  32  is installed between bricks  20   c  and  20   d,  between bricks  20   d  and  20   a , between bricks  20   a  and  20   b,  between bricks  20   b  and  20   c  and between bricks  20   c  and  20   f.    
         [0058]     Alternatively, it may not be necessary to install a spacer  32  between every one of bricks  20  along lintel  24 . It is desired to install enough spacers  32  so that adequate drainage is allowed through weep holes  40  to drain moisture from wall system  10 . For example, it is possible not to install a spacer  32  between bricks  20   d  and  20   a  or between bricks  20   b  and  20   e.    
         [0059]     Spacer  32  can be constructed of polyvinylchloride, for example, using conventional plastic molding techniques. In one embodiment, spacer  32  is formed into a strip of spacer elements  42 .  FIG. 7  illustrates spacers  32  in two strips formed from eight (8) spacer elements  42  (four in each of the two strips). The two strips are temporarily joined at the ends with bars  44 .  
         [0060]     Each spacer element  42  contains side edges  36  which are angled back from top surface  34 . A transverse groove serving as break notch  46  is formed between each adjoining spacer element  42  and between bars  44  and spacer elements  42 . Spacer elements  42  have a longitudinal dimension such that an integral number of spacer elements  42  can be used to form common depth dimensions for common modular building components. For example, in a preferred embodiment, each spacer element has a longitudinal dimension of 2¼ inches (5.7 centimeters). This allows two spacer elements  42  to form one spacer  32  having a length of 4½ inches (11.4 centimeters) which is approximately equal to the width (depth) of commonly available standard size of brick  20 . Up to four (4) spacer elements  42  can be used together to accommodate a veneer wall  18  thickness of up 9 inches (22.9 centimeters).  
         [0061]     Details of the installation of spacers  32  to form head joint drainage devices are illustrated in  FIGS. 8 through 15 . As shown in  FIG. 8 , a steel lintel  24  is prepared with flashing  28 . No mortar  30  is used on top of lintel  24  or flashing  28 . Bar  44  is snapped from spacers  32  ( FIG. 9 ) and one or more spacer elements  42  are separated by hand from the remainder of the spacer strip (if any). The number of spacer elements  42  used corresponds to the depth of the bricks into which the spacer  32  is to be placed. After a brick  20  is placed on lintel  24  (and flashing  28 ), spacer  32  is placed ( FIG. 10 ) beside brick  20  with top surface  34  facing up. A side view of spacer  32  so placed is shown in  FIG. 11 . Note that spacer  32  has a length which is at least as great as the depth of brick  20 .  FIG. 12  illustrates two spacers  32  placed between three bricks  20  creating two weep holes  40 . A bed of mortar  30  is spread conventionally ( FIG. 13 ) to the top of bricks  20  and mortar  30  is tuck pointed in head joints between bricks  20  ( FIG. 14 ).  FIG. 15  illustrates the finished wall system  10  in a close-up detail at the head joint at the top left corner of window opening  22 . The mortar  30  has been tooled and brushed creating a professionally finished wall veneer  18 . Spacers  32  create weep holes  40  allowing moisture in wall system  10  to drain from the wall at the top of the head joint.  
         [0062]     Although various embodiments of the present invention have been described as being constructed from particular materials, e.g., steel, plastic, polyvinylchloride, it is to be recognized and understood that other materials could also be used.  
         [0063]     While the present invention has been described through the use of bricks as modular building products, it is to be recognized and understood that other modular building products could also be used such as concrete blocks or stone, either natural or synthetic.  
         [0064]     While top surface  34  of spacer  32  has been described as being formed as a solid surface, it is to be recognized and understood that other constructions are possible. For example, top surface  34  could be a grid or mesh as long as such top surface  34  substantially prevents mortar  30  from penetrating top surface  34  and clogging weep hole  40 .  
         [0065]     Although side edges  36  have been described as being tapered or angled back along each spacer element, it is to be recognized and understood that other configurations are also possible and contemplated. For example, side edges  36  need not be tapered or angled back to achieve the functional result required. Further, both ends of sides edges need not be tapered or angled back, i.e., perhaps side edges  36  may only to tapered or angled back from front edge  38  of top surface. Additionally, it is not necessary that side edges  36  be solid. Side edges could be formed from posts or other structural elements designed to support top surface  34  from lintel  24 /flashing  28  during tuck pointing of mortar  30 .  
         [0066]     While various embodiments of the invention have been described as used in conjunction with lintel  24 , it is to be recognized and understood that such construction techniques, structures and methods apply equally well to wall systems, head joints and methods of drainage used in conjunction with shelf angles.  
         [0067]     Various modifications and alterations of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that this invention is not limited to the illustrative embodiments set forth above.

Summary:
A wall system, head joint drainage device and method adapted to allow drainage of moisture from a head joint of a structure meeting a horizontal interruption when the wall system is formed with a plurality of building products set with mortar forming a mortar joint between adjacent ones of the plurality of modular building products. A spacer has a top portion, having a length approximately equal to a depth of the plurality of building products and a width approximately equal to a width of the mortar joint, adapted to block the mortar from reaching the horizontal interruption and has a side portion adapted to keep the portion a distance away from the horizontal interruption, the distance allowing moisture drainage from the head joint.