Patent Publication Number: US-2022213680-A1

Title: Exterior insulated finish wall assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/983,684, filed Aug. 3, 2020, entitled EXTERIOR INSULATED FINISH WALL ASSEMBLY, which is a continuation of U.S. patent application Ser. No. 16/580,504, filed Sep. 24, 2019, entitled EXTERIOR INSULATED FINISH WALL ASSEMBLY, now U.S. Pat. No. 10,731,334, issued Aug. 4, 2020, which is a Continuation of U.S. patent application Ser. No. 15/977,462 filed on May 11, 2018, entitled EXTERIOR INSULATED FINISH WALL ASSEMBLY, now U.S. Pat. No. 10,472,820, issued Nov. 12, 2019, which claims priority under 35 U.S.C. § 119(e)(1) to U.S. Provisional Patent Application Ser. No. 62/504,875, filed May 11, 2017, entitled EXTERIOR INSULATION AND FINISH WALL DRAINAGE SYSTEM, the entire disclosures of each of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     Improvements in building construction have resulted in wall assemblies that are highly energy efficient. These wall assemblies are often highly insulated and include sealed joints around windows and doors to prevent drafts. While these walls have high thermal efficiency, it has been observed that moisture can potentially accumulate inside the wall over time due to naturally occurring temperature and/or humidity gradients. In addition, moisture can potentially accumulate inside sealed walls due to water running down a steeply pitched roof, for example in the case where the joint/seal between the wall and the roof deteriorates and provides an ingress location for water into the wall. 
     Moisture trapped inside of the walls includes moisture vapor and bulk water, such as condensation. Condensation can form inside a wall due to temperature differences across the insulated walls. For example, during typical northern cold winter months, the air outside of an insulated wall is cold and dry, and the air inside of the wall is relatively warm and humid. Thus, a natural humidity gradient is formed that drives moisture vapor in the air inside the wall toward the exterior of the wall. Large gradients between outside and inside air temperature and humidity can lead to a significant accumulation of moisture condensation within the insulated wall. Exterior wall systems can employ drainage features, such as weep holes, for example, that can be aesthetically unacceptable. Often exterior insulation and finish systems (EIFS) do not include drainage features, and particularly, do not include aesthetically acceptable drainage features to divert water from a drainage plane of an exterior wall system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partial exploded cross-sectional view of an exterior insulated finish wall assembly in accordance with aspects of the present disclosure. 
         FIGS. 2A-2B  are front and back views of an exterior wall member of the exterior insulated finish wall assembly in accordance with aspects of the present disclosure. 
         FIGS. 3A-3B  are front and back views of an insert member of the exterior insulated finish wall assembly in accordance with aspects of the present disclosure. 
         FIG. 4  is a partial cross-sectional view of an exterior insulated finish wall system in accordance with aspects of the present disclosure. 
         FIG. 5  is a schematic representation of various layers of an exterior wall panel system in accordance with aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the following Detailed Description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” “leading,” “trailing,” etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims. 
     As used herein, moisture includes bulk liquid water, such as rain or rain droplets, and moisture vapor, such as humidity contained in the air. 
     As used herein, fluid is a broad term that includes both gases and liquids. 
     As used herein, barrier means to substantially prevent or deny the through-passage of air and to substantially prevent or deny the passage of moisture vapor. Thus, barrier as used herein means to substantially prevent the through-passage of moisture through the barrier, whether the moisture is in the form of moisture vapor or bulk liquid. 
     As defined herein, building envelope assembly is a broad term which includes any assemblies which separate interior and exterior environments of a building. A building envelope assembly serves to protect the indoor environment from the elements of nature (e.g., rain, snow, etc.) and facilitate its climate control. A building envelope assembly as defined herein includes vertical assemblies, such as walls, and non-vertical assemblies, for example. 
       FIG. 1  illustrates a partial exploded cross-sectional view of an exterior insulated finish wall assembly  10  in accordance with one embodiment of the present disclosure. The exterior insulated finish wall assembly  10  can be included in an exterior insulation and finish system(EIFS) wall  100  (see e.g.,  FIG. 4 ) and as part of a building envelope assembly. In general, exterior insulated finish wall assembly  10  includes an exterior panel member  12  and an insert member  14 . When assembled, the exterior panel member  12  and the insert member  14  can define a drainage channel  16  therebetween (see e.g.,  FIG. 4 ). The exterior panel and insert members  12 ,  14  can each include a substrate layer  18  and a base coat  20 , as described further below. 
     The rigid insulative substrate  18  can be formed of rigid foam insulation, such as expanded polystyrene (EPS) or extruded polystyrene (XPS), for example. Other suitable types of rigid insulation or substrates are also acceptable. The rigid insulative substrate  18  is a suitable thickness and material to provide the desired insulative value (R-value) and comply with applicable building codes. The rigid insulative substrate  18  can have any suitable thickness. In one embodiment, the rigid insulative substrate  18  of the base member has a thickness of 2 inches and the insert member has a thickness of approximately 1 inch. The rigid insulative substrate  18  can also include recesses, cutouts, bevels, channels, grooves, etc. (e.g., for architectural or other purposes) that vary the thickness across select portions of the rigid insulative substrate  18 , without changing the overall insulative value of the exterior wall insulation and finish assembly  10 . The rigid insulative substrate  18  can include a single or multiple sections fit together to form a continuous layer. The rigid insulative substrate  18  can be formed into any appropriate shape including, but not limited to, planar, curved, or angled. The exterior surface of the rigid insulative substrate  18  can be scarified or rasped to provide a textured bonding surface for adherence of coatings or finishes. 
     As illustrated in  FIG. 1 , the base coat  20  can be selectively applied over the surfaces of the rigid insulative substrate  18  of the exterior panel member  12  and the insert member  14 . The base coat  20  can be an acrylic cementitious coating or an acrylic non-cementitious coating, for example. The base coat  20  can be fiber-reinforced. Other coatings can also be acceptable. The base coat  20  can include adhesive properties to self-adhere to surfaces. Alternatively, or in addition, a mesh  21  can be applied to the rigid insulative substrate  18  to aid in bonding of the base coat  20  with the rigid insulative substrate  18 . The mesh  21  can be embedded in the base coat  20  on the rigid insulative substrate  18 . In one example, the mesh  21  is a fiberglass mesh, although other types of reinforcing mesh can also be suitable. The mesh  21  can be self-adhesive or adhered to the rigid insulative substrate  18  with an adhesive. The mesh  21  can extend past the termination of the base coat  20  or terminate with the base coat  20 , as appropriate for proper adhesion between the base coat  20  and the rigid insulative substrate  18 . The base coat  20  can be disposed on the rigid insulative layer  18  as suitable to provide applicable fire code ratings and/or to provide reinforcement to the rigid insulative layer  18 . 
     With additional reference to  FIGS. 2A-2B , the exterior panel member  12  includes a body portion  22  and a tail portion  24  extending from the tail portion  24 . The body portion  22  defines a top edge  26  of the exterior panel member  12  and the tail portion  24  defines a bottom edge  28  of the exterior panel member  12 . The exterior panel member  12  has a first, or exterior, surface  30  and a second, or interior surface  32  extending between opposing side edges  34 ,  36  and having a first thickness. The first and second surfaces  30  can be generally planar. The tail portion  24  includes a recess  38  extending between the opposing side edges  34 ,  36 . The tail portion  24  has a second thickness less than the first thickness. In one example, the second thickness of the tail portion  24  is approximately half of the first thickness of the body portion  22 . In one embodiment, the tail portion  42  maintains a ¾″ thickness. The recess  38  extends into the panel member  12  from the second surface  32  partially toward the first surface  30  at the tail portion  24 . The recess  38  extends longitudinally along the bottom edge  28  and is defined by a recessed surface  40  and a sloped surface  42  extending from the second surface  32  to the recessed surface  40 . The sloped surface  42  forms an obtuse angle with the second surface  32 . In this manner, the sloped surface  42  is sloped downward from the second surface  32  toward the recessed surface  40 . The recess  38  is shaped and sized to accommodate the insert member  14  and form the drainage channel  16  between the exterior wall member  12  and the insert member  14 . The tail portion  24  of the exterior panel member  12  defines a recess  38  configured to accommodate the insert member  14  and the drainage channel  16  formed therebetween. In another embodiment, a first face  44  of the tail portion  24  is coplanar, or substantially coplanar, with the first surface  30  of the body portion  22 . In one embodiment, the first face  44  of the tail portion  24  can be slightly recessed from the first surface  30  of the body portion  22 . Although, illustrated as angled, or non-perpendicular, the bottom edge  28  of the tail portion  24  can be squared, rounded, angled, or other desired shape. 
     The exterior wall member  12  can include the base coat  20  disposed on, and encapsulates, the bottom edge  28 , the recessed surface  40 , and the first face  44  of the tail portion. In one embodiment, the base coat  20  extends approximately 2 ½″ from the bottom edge  28  along the recessed surface  40  and the first face  44 . Other suitable distances of coverage can also be acceptable. A groove  45  can be included in the rigid insulative layer  18  along the first surface  30 , above a top terminating edge of the base coat  20 , to provide a transition of the body portion  22  to facilitate rasping of the insulation to prepare for additional finishes, for example. The first surface  30  of the body portion  22  can be generally planar to an exterior surface of the base coat  20  on the tail portion  24 . 
     With continued reference to  FIG. 1  and additional reference to  FIGS. 3A-3B , the insert member  14  includes a front face  50 , a back face  52 , a bottom face  54 , and a top face  56 . The insert member  14  extends between opposing sides  58 ,  60  and can have a length equivalent to a length of the exterior panel member  12 . The top face  56  is shaped and sized to correspond with the sloped surface  42  of recess  38  formed at the tail portion  24 . The top face  50  can be orientated at a  45  degree angle, or other suitable angle, to be sloped from the back face  52  to the front face  50 , for example. The top face  56  can be formed at any appropriate angle to facilitate moisture/water to flow by gravity from interior side of the exterior wall insulation finish assembly  10  toward an exterior. The front face  50  extends parallel to the recessed surface  40  of the tail portion  24 . The back face  52  can be parallel to the front face  50 . The base coat  20  can be disposed on, and encapsulate, the bottom face  54 , the front face  50 , and the top face  56 . 
     With additional reference to  FIGS. 4 and 5 , the exterior wall insulation finish assembly  10  can be assembled to form an exterior wall panel system  100 . The exterior wall panel system  100  can include framing  62 , a substrate layer  64 , and moisture barrier  66 . The framing  62  can be metal stud framing spaced at 16 inches on-center, or other appropriates pacing, for example. Insulation, such as unfaced fiberglass bat insulation, can be disposed between framing members to provide additional insulative value, if desired (not shown). Alternatively, framing  62  can be concrete, masonry, or other rigid material. The substrate layer, or sheathing,  64  can be gypsum sheathing, exposed oriented strand board (OSB), exterior or exposure 1 grade plywood, or a masonry substrate such as cement masonry unit blocks or bricks, for example. The sheathing  64  can extend across a length and width of the framing  62 , for example, to provide a surface to which other layers can be disposed and/or attached. The sheathing  64  can be adhered or mechanically attached to the framing  62 . 
     The moisture barrier  66  can be disposed across the outer surface of the sheathing  64 . The moisture barrier  66  can be a membrane formed of latex-based coating serving to resist moisture and air penetration. The moisture barrier  66  can be fluid applied or applied as a sheet building wrap. A flashing membrane  68  that is resistive to fluid (e.g., air and water) can be selectively applied to the substrate  64 . In some embodiments, the moisture barrier  66  and the flashing membrane are formed of the same material. The flashing membrane  68  is a fluid resistive membrane barrier over the sheathing  64  and to bridge across sheathing joints at openings, such as horizontal joints. The flashing membrane  68  can be a liquid applied membrane or a sheet membrane. The flashing membrane  68  can be a flexible, water-based polymer material applied over a mesh, or non-woven blend fabric. In one example, Dryvit AquaFlash® is used. The flashing membrane  68  can be applied along a lower portion of the sheathing  64  and along a bottom surface of the framing  62  and the sheathing  64  within a joint space. 
     The insert member  14  of the exterior wall insulation finish assembly can be attached to the sheathing  64  over the flashing membrane  68  with adhesive  58  or other means. The flashing membrane  68  can then be applied over the top face  56  and front face  50  of the insert member  14  and extending above the top face  50  onto the moisture barrier  66  and/or sheathing  64  to prevent moisture from between the insert member  14  and the sheathing  64  and provide drainage along the front face  50 . 
     Adhesive is applied to adhere the exterior wall member  12  to the sheathing  64  and/or moisture barrier  66 . The adhesive can be applied with a notched trowel in a manner that provides vertical grooves formed by the notches, within the adhesive. When assembled, the bottom edge  28  of the exterior wall member  12  can extend generally planar to the bottom face  54  of the tail portion  14 . The bottom edge  28  can be substantially aligned with the bottom face  54 . The drainage channel  16  can be formed between or within the exterior panel member and insert members  14 ,  16  with the flashing membrane  68  extending therethrough. 
     The interior or, second and back surfaces  32 ,  52 , of the exterior wall member  12  and insert member  14  extend along a first plane when assembled. The flashing membrane  68  can channel, or direct, moisture from an interior surface of the rigid insulative layer  18  along the top face  56  and front face  50  with the aid of gravity without moisture penetrating either the insert member  14  or the exterior wall member  12 . Sealant  74  and backer rod  76  can be included at horizontal and vertical joints between panels  100 , etc. The sealant  74  is disposed behind, or interior to, the front face  50  of the insert member  14  to allow drainage from between the insert member  14  and the exterior wall member  12  to exterior of the wall system  100 . 
     A finish coating  70  can be included over the exterior wall member  12 . The finish coating  70  can include adhesive properties to self-adhere to surfaces. The finish coating  70  can include one or more layers that can be troweled on or spray applied. At least one of the coating layers can be an acrylic copolymer coating, such as Dryvit&#39;s Dirt Pickup Resistance (DPR) finishes, for example. Other or additional exterior coatings can also be acceptable. 
     In accordance with aspects of the present disclosure, the wall system  100  can be prefabricated wall panels fabricated in a controlled manufacturing facility and delivered to a building project site or can be assembled at a building project site. During fabrication, the rigid insulative layer  18  of the exterior wall member  12  and the insert member  14  can be formed from a standard sheet of rigid insulation material and cut to the desired size and shape using computer numerical controlled (CNC) machining. The mesh  21  can adhered to the formed rigid insulative layer  18 . For example, a 3 ½″ or 4″ wide self-adhesive fiberglass mesh can be applied to the rigid insulative layer  18 . The base coat  20  can be a liquid coating applied using a mud box including a template corresponding to the surfaces of the formed rigid insulative layer  18  to which the base coat  20  is to be applied and feeding the mesh  21  applied exterior wall member  12  and insert member  14  through the mud box either mechanically or manually. Alternatively, the base coat  20  can be applied by machine, spraying, or hand troweling. The mesh  21  and base coat are cured onto the rigid insulative layer  18 . 
     The framing  62  can include a base plate, a top plate, and vertical stud members extending between the base plate and the top plate. The sheathing layer  64  can be attached to the framing  62 . Alternatively, or additionally, a hat channel can be disposed along a surface of the sheathing  64 . The sheathing  64  can be formed of standard sheets of rigid insulation assembled and abutting edge to edge and/or as desired to form the desired sheathing layer and attached to the framing  62  with adhesive, for example. The moisture barrier  66  and flashing membrane  68  can be disposed over the insert member  14 , sheathing  64  and framing  62  to form an edge wrap along terminating edges of the panel assemblies. Edges of the wall panel body can include edge wraps disposed on all or some perimeter edges of the wall panel body. 
     The assembled exterior wall panels  100  can be any desired shape. For example, the assembled wall panels  100  can include sections that are angled relative to one another. Grooves or other desired surface features can be included for aesthetic or other purposes. In other examples, openings can be included for windows, doors, electrical and mechanical equipment, etc. The wall panels  100  can be ready for installation and loaded for delivery to a jobsite for installation on a building structure. The wall panels  100  can be attached to a floor slab or other structural member of a building structure with embedded angle, clips, or other mechanical methods. 
     Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof