Abstract:
A method and system for providing an insulative wall structure. The insulative wall structure includes first and second vertical longitudinal supports, which are separated horizontally, creating a space therebetween. The insulative wall structure also includes a thermal insulation member placed within the space between the first and second vertical longitudinal supports so that it is engaged with both of the vertical longitudinal supports. The resulting wall structure reduces thermal transmissions through the first and second vertical longitudinal supports.

Description:
TECHNICAL FIELD 
       [0001]    The present invention is directed to wall structures in construction, and more particularly, to an insulated wall structure and methods for its construction. 
       BACKGROUND OF THE INVENTION 
       [0002]    A typical wall panel used in construction today includes a frame comprising load bearing members spaced vertically apart from each other and bound by upper and lower elements. The frame is generally made from wood or metal, however, other materials may be used. In general, a wood frame is trimmed to the desired dimensions to form the frame, and a metal frame is bent to the desired dimensions. 
         [0003]    Once the frame is erected, insulation is installed into the frame. Typically, fiberglass insulation is used. The fiberglass insulation is a soft material and is placed between the load bearing members. At the junction where the fiberglass meets load bearing members, there are often small voids. These voids allow for thermal transmission reducing the insulation effectiveness of the wall. Similarly, the voids provide a path for sound to transmit through the wall. Additionally, because the fiberglass insulation is a soft material, it often sags after being installed into the frame due to gravity. This creates more voids between the insulation and the load bearing members and reduces the thermal properties and sound reducing properties of the wall panel even further. 
         [0004]    While such wall panels have served in the construction of buildings for decades, today&#39;s greater demand for thermal efficiency has affected the choice of building materials being used. Additionally, wall structures capable of absorbing sound waves to decrease noise levels heard through the walls are also in demand. 
         [0005]    Therefore, there is a need for wall structures in the construction of buildings that are capable of providing thermal efficiency and reducing sound transmission at a reasonable cost. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention is directed toward an insulated wall structure and methods for its construction. In one aspect of the invention, the wall structure comprises first and second vertical longitudinal supports, where the supports are separated horizontally and create a space therebetween. A rigid insulation member is placed within the space and bonded to the first and second vertical longitudinal supports. 
         [0007]    According to a second aspect of the invention, the method for erecting a wall structure includes bonding a first end of a rigid insulation member to a first longitudinal support and bonding a second end of the rigid insulation member to a second longitudinal support. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a schematic drawing of a wall structure according to one embodiment of the invention. 
           [0009]      FIG. 2A  is a schematic drawing of a wall structure without openings according to one embodiment of the invention. 
           [0010]      FIG. 2B  is a cross sectional view of the wall structure in  FIG. 2A  according to one embodiment of the invention. 
           [0011]      FIG. 3A  is a schematic drawing of a wall structure without openings according to one embodiment of the invention. 
           [0012]      FIG. 3B  is a top down view of the wall structure in  FIG. 3A  according to one embodiment of the invention. 
           [0013]      FIG. 4  is a cross section of an insulation member according to one embodiment of the invention. 
           [0014]      FIG. 5  is a cross section of a hat channel for creating an air gap between an outer surface of a wall structure and an exterior surface of a building according to one embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0015]    Embodiments of the present invention are directed toward wall structures in construction, and more particularly, one or more embodiments are directed to an insulated wall structure and methods for its construction. Certain details are set forth below to provide a sufficient understanding of the embodiments of the invention. However, it will be clear to one skilled in the art that various embodiments of the invention may be practiced without these particular details. 
         [0016]      FIG. 1  is a schematic drawing of a wall structure  100  according to one embodiment of the invention. The wall structure  100  includes insulation members, such as  120 , between load bearing members, such as  110   a  and  110   b . The wall structure  100  includes many wall bearing members and insulation members as can be seen in  FIG. 1 , however, in the interest of brevity only load bearing members  110   a  and  110   b  and insulation member  120  will be described. 
         [0017]    Insulation member  120  is placed between and in contact with load bearing member  110   a  and load bearing member  110   b  and has been called an Enviro-Envelope System. The load bearing members  110   a  and  110   b  primarily provide support for vertical loading, such as weight borne by a truss. In addition, however, the load bearing members  110  may provide horizontal support for loads that transverse a member within the wall structure  100 . The wall structure  100  in  FIG. 1  is an external wall structure for being installed within a building structure (not shown). However, as will be clear to a person of ordinary skill in the art, the wall structure  100  may also be used for internal wall structures. 
         [0018]    The insulation member  120  is bonded to the load bearing members  110   a  and  110   b . For instance, the insulation member  120  may be secured to the load bearing members  110   a  and  110   b  by an adhesive. In one embodiment, the insulation member  120  is a rigid material, such as polystyrene. In another embodiment, the insulation member  120  is a semi-rigid material, such as a rubber based material. The rigid or semi-rigid insulation member may improve the structural integrity of the wall structure  100 . The wall structure  100  is bound on top by a top track member  140  and is bound on bottom by a bottom track member  142 . 
         [0019]    The wall structure  100  has a window opening  130  and door opening  132 , however, other openings may be used with the wall structure  100 . The height of the wall structure  100  varies and often depends on the building structure in which the wall structure  100  will be installed. Typically, the height of the wall structure  100  will vary between approximately 8-40 feet. For instance, in one embodiment, the height of the wall structure  100  is about 10 feet. In another embodiment, the wall structure  100  is approximately 30 feet tall. Above an opening, is an insulative beam providing support for the downward vertical load that is applied from above. For instance, beam  134  is above the window opening  130  and is secured to insulative member  110   a  by connection  136 . The beam comprises two C-channels or U-channels with a rigid material between them, such as polystyrene. The channels may be secured to the rigid material by an adhesive. The beam and connection are further described in U.S. Pat. No. 5,678,381, which is incorporated for all purposes in its entirety herein. Along the sides of the opening are king studs, which support the beam. The king studs consist of two U-channel or C-channel load bearing members facing one another with a rigid insulation member in between. The U-channel or C-channel members may be secured to the rigid insulation member by an adhesive. The U-channel or C-channel members may be overlapping, touching, or separated by a distance. 
         [0020]    One side of the wall structure  100  is in contact with an exterior surface (not shown), and the other side of the wall structure  100  is in contact with an interior surface (not shown). The exterior surface may be any type of exterior building material, such as stucco, wood and vinyl siding, concrete, or brick. The interior surface may be any type of interior wall material, such as sheetrock. 
         [0021]      FIG. 2A  is a schematic drawing of a wall panel or wall structure  200  without openings, and  FIG. 2B  is a cross sectional view  250  of the wall structure  200  in  FIG. 2A  according to one embodiment of the invention. The width of the wall structure  200  is approximately 8 or 10 foot wide, however, as will be clear to a person having ordinary skill in the art other widths may be used. 
         [0022]    The load bearing members in  FIGS. 2A and 2B  are similar to those in  FIG. 1 . Each load bearing member has similar features, therefore, in the interest of brevity only load bearing members  210   a  or  210   b  will be described. Load bearing members  210   a  and  210   b  are elongated and typically made from a single integral piece of material. The material is typically any material capable of providing structural support for vertical loading and may also be capable of supporting horizontal loading. In one embodiment, the load bearing members  210   a  and  210   b  are made from sheet metal, such as galvanized steel or aluminum. In another embodiment, the load bearing members  210   a  and  210   b  are made from wood. However, as will be clear to a person having ordinary skill in the art, other materials may be used. For instance, in other embodiments, fiberglass or other composite materials are used. 
         [0023]    Each load bearing member  210   a  typically has a constant cross section along the length of the member  210   a . In one embodiment, the load bearing members  210   a  have channel cross sections, such as a C-channel or a U-channel. For instance,  FIG. 2B  shows C-channel cross sections  211   a  and  211   b  for load bearing members  210   a  and  210   b . In reference to both  FIGS. 2A and 2B , the C-channel cross sections  211   a  and  211   b  of load bearing members  210   a  and  210   b , respectively, include a web  214   a  and  214   b  extending between first legs  215   a  and  215   b  and second legs  216   a  and  216   b , respectively. Looking at cross section  211   a , the first and second legs  215   a  and  216   a  are substantially perpendicular with the web  214   a . The first leg  215   a  is substantially parallel with the second leg  216   a . C-channel cross section  211   a  is installed into the wall structure  200  so that its web  214   a  is approximately parallel to the web  214   b  of C-channel cross section  211   b . In one embodiment, the legs,  215   a ,  216   a ,  215   b , and  216   b  are of the same length. 
         [0024]    The C-channel or U-channel may be formed by bending a length of sheet metal along two parallel lines. Typically, between 14 and 25 gauge sheet metal has been found suitable for many applications, although other gauges can be chosen as desired. The gauge of the sheet metal is generally determined by the height of the wall structure or the expected vertical or horizontal loading to be applied to the load bearing member. If the load bearing member is made from a formed material, such as fiberglass or carbon fiber composites, the load bearing members are fully formed before their shape is set by some further action, such as a thermal or chemical reaction. At joint  205 , the wall structure  200  intersects with the beginning of another wall structure  201 . Two C-channel load bearing members are positioned so that a web of the first load bearing member is adjacent the web of a second load bearing member. 
         [0025]    In reference again to  FIG. 1 , at a first end  102  of the wall structure  100 , a corner load bearing member  103  is secured to an insulation member. The corner load bearing member  103  may comprise two C-channels or U-channels, where the legs of the channels face each other. For instance, the legs of a first C-channel load bearing member may overlap or touch the legs of a second C-channel load bearing member. An example of a corner load bearing member is described further in U.S. Patent Application No. 2007/0113506, which is incorporated for all purposes and in its entirety herein. 
         [0026]      FIG. 3A  is a close up view of a schematic drawing of a portion  206  of the wall structure  200  from  FIG. 2 ; and  FIG. 3B  is a top down view  208  of the portion  206  of the wall structure in  FIG. 3A  according to one embodiment of the invention. In reference to  FIG. 3A , each load bearing member is secured to a top track  240 . In particular, load bearing member  210   b  is secured to the top track  240  at joint  217 . The load bearing member is typically secured to the top track by a nail or screw, however, other known types of attachment may also be used. As will be clear to a person having ordinary skill in the art, the bottom track, such as the bottom track  142  in  FIG. 1 , is similarly secured to each load bearing member. 
         [0027]    As in  FIGS. 2A and 2B , the load bearing members  210   a  and  210   b  are C-channels, and each insulation member is bonded to each load bearing member. By bonding the insulation member to the load bearing members, a seal is created between the insulation member and the load bearing member. This seal prevents voids between the insulation members and the load bearing members. Therefore, the thermal properties of the wall structure as a whole increase. Similarly, the wall structure is able to absorb sound more easily. Additionally, the seal provided by bonding the insulation members to the load bearing members assists in preventing moisture from entering the wall structure and causing damage within the wall. The structural integrity of the wall increases as well. For instance, the sheer capacity and the lateral strength of the wall structure is greater over wall structures used in the prior art. 
         [0028]      FIG. 3B  shows first and second legs  215   b  and  216   b  of the load bearing member  210   b , however, from a top view, this is typically not visible as the top track will cover all or portions of the first and second leg  215   b  and  216   b . As will be explained further below, an outer surface of the first and second leg  215   b  and  216   b  of the load bearing member  210   b  is flush with the insulation member  220 . Each of the top and bottom tracks may be two L-channels, one leg of the L-channel on a top of the wall structure and the other leg of the L-channel on a side of the wall structure. For instance,  FIGS. 3A and 3B  show the top track  240  as being two separate L-channels  241  and  242 , one on each side of the wall structure  200 . In another embodiment, each of the top and bottom tracks may be a single C-channel, where the web extends along the top surface of the wall panel and the legs extend along the side of the wall panel. 
         [0029]      FIG. 4  is a cross section of an insulation member  400  according to one embodiment of the invention. The insulation member  400  may be formed from any material having suitable thermal conductivity, such as less than 0.1 W/mK. In addition, the insulation member may be formed from any material having suitable sound absorption properties. As stated above, the insulative material is a rigid or semi-rigid material. In one embodiment, the insulation members are preformed blocks made from expanded or extruded polystyrene. In another embodiment, the insulation member is made from polyisosanurate. Because polyisosanurate is a relatively soft material, it may require paper to surround the material. In other embodiments, insulative mixtures, such as a mixture of mud and straw, may be used as the insulation member. 
         [0030]    The cross section of the insulation member  400  has a first end  401  and a second end  402 . The cross section of the insulation member typically has a width approximately equal to a length of the web of the load bearing member. In one embodiment, the width, W, of the insulative material  400  is approximately 6 inches. A length, L, of the cross section of the insulation member  400  is generally equal to the desired distance between the load bearing members. In one embodiment, the length of the insulation member  400  is approximately 15⅞ inches. However, as will be clear to a person having ordinary skill in the art, the dimensions of the insulation member and the load bearing member may vary. The insulative material  400  has cutouts to allow for the load bearing member to fit within the insulative material  400  so that the load bearing member and the insulative material are flush with one another. For instance, in one embodiment the first end  401  of the insulative material comprises two notches  410  and  411 . The notches  410  and  411  extend an entire vertical length (not shown) of the insulative material  400 . Typically, the notches  410  and  411  have dimensions similar to the dimensions of the legs  215   b  and  216   b  of the load bearing member  210   b  in  FIGS. 3A and 3B . This is so that an outside edge of the leg of a load bearing member and an outside edge of the insulative material may be generally flush with one another. For instance, in one embodiment each notch  410  and  411  removes ½ inch from the width of the cross section of the insulative material  400  and removes 1½ inches from the length. In another embodiment, each notch  410  and  411  removes ⅜ inch from the width of the cross section of the insulative material  400 . 
         [0031]    In one embodiment, an air gap between the outer surface of the wall structure  200  and an exterior surface (not shown) may be provided to create a thermal break. Air is known to have low thermal conductivity and thus, an air gap reduces the thermal transmission through the load bearing members  210   a  and  210   b . In one embodiment and in reference to  FIGS. 3A and 3B , the air gap between the wall structure  200  and the exterior surface is generated by placing hat channels  246  horizontally across the wall structure  200 . In particular,  FIG. 3A  shows the hat channel  246  attached to the outer surface of the wall structure.  FIG. 5  shows a cross section of a hat channel  246  according to one embodiment of the invention. The hat channel  246  is ⅞ inch tall. Thus, the hat channel  246  applied to the outer surface of the wall structure  200  in  FIGS. 3A and 3B  would create an air gap of about ⅞ between the outer surface of a wall structure  200  and an exterior surface. However, as will be clear to a person of ordinary skill in the art, other dimensions for the hat channel may be used. 
         [0032]    In another embodiment, a barrier may be used to reduce the thermal transmission through the load bearing members  210   a  and  210   b . The barrier is secured to the outer surface of the wall structure  200  between the wall structure  200  and the exterior surface. The barrier has a low thermal conductivity, such as less than 0.1 W/mK. In one embodiment, the barrier material is polystyrene. The polystyrene may be extruded or expanded. In one embodiment the polystyrene is ½ inch thick and may be applied in sheets. The sheets may be of varying size. In one embodiment, the sheet is 4 feet×8 feet or 4 feet by 10 feet. The exterior surface is secured to the outer surface of the barrier material. Both the air gap or the barrier reduce the thermal transmission through the wall structure, particularly through the load bearing members. 
         [0033]    By utilizing the entire wall systems described above, the wall structure will have improved structural integrity, thermal resistance, and sound absorption properties. In particular, a wall structure comprising the corner studs, king studs, beam, and structural members therebetween will greatly improve the structural integrity, thermal resistance, and sound absorption over wall structure found in the prior art. 
         [0034]    Although the present invention has been described with reference to the disclosed embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. Such modifications are well within the skill of those ordinarily skilled in the art. Accordingly, the invention is not limited except as by the appended claims.