Abstract:
Disclosed are an insulation product and an insulation system incorporating such a product for insulating exterior walls, particularly masonry walls, that incorporates a wicking media to transport condensate away from the interface between the insulating product and the exterior wall. The condensate will be removed to a more interior location where it can evaporate and/or be transferred to and held in a sorbent material until conditions allow permit evaporation. The insulation system includes an integrated support element that can be used to increase the rate of evaporation via various methods and/or improve the aesthetic appearance of the insulating product. The evaporation rate may be improved through the use of increased wicking material area, secondary evaporative surfaces, heating and/or forced or natural convection.

Description:
TECHNICAL FIELD AND INDUSTRIAL APPLICABILITY  
       [0001]     This invention relates generally to a method and apparatus for insulating masonry walls that provides improved moisture control at the interface between the insulation material and the masonry wall. More particularly, this invention pertains to an insulating process and apparatus in which one or more vapor barrier, sorbent and wicking materials are used in an insulation product that is applied to a masonry wall to reduce or prevent the formation of liquid water on the masonry wall.  
       BACKGROUND OF THE INVENTION  
       [0002]     The exterior walls of a building are typically insulated in order to reduce the heating and cooling demands resulting from variations between the exterior temperature from the desired interior temperature. A wide range of fibrous, solid and foam insulating materials have been used to achieve this insulation, with a common insulating material being faced or unfaced batts of mineral or glass fibers.  
         [0003]     When using a faced insulating product in which a facing layer, such as asphalt-coated Kraft paper or a polymeric film, is adhered to the insulating layer, the insulation product is typically installed with the facing layer positioned toward the interior space. This orientation tends to reduce infiltration or diffusion of the moisture-laden interior air through the insulating layer to the interface between the insulating product and the exterior wall. Particularly in climates with long heating seasons and/or extremely cold temperatures, using faced insulation products limits the amount of moisture from the interior air that can reach the cooler exterior wall and condense to form liquid water on the surface of the exterior wall.  
         [0004]     As used herein, masonry walls include constructions utilizing clay brick, concrete brick or block, calcium silicate brick, stone, reinforced concrete and combinations thereof. Water present at the interface between the insulating product and the inside surface of the exterior wall and/or the outer portion of the insulation product is associated with a host of problems including mold growth, efflorescence, reduced insulating efficiency and, if sufficiently cold, frost spalling resulting from water freezing and expanding within cracks and gaps in the masonry.  
         [0005]     A major contributing factor to the accumulation of water at the interface and the resulting decreased performance of the associated masonry wall system is the leakage of warm humid air through the building envelope to surfaces that are at temperatures below the dew point of the adjacent air and the associated accumulation of condensation within the insulating layer and/or on the inside surface of the exterior wall.  
         [0006]     A need thus exists for an improved method of insulating exterior walls, particularly masonry walls, that provides improved control of water, particularly that resulting from the condensation of water vapor, at the interface between an inside surface of the exterior wall and the outer surface of the insulation product applied to the wall.  
       SUMMARY OF THE INVENTION  
       [0007]     To solve the problems outlined above, the present invention provides an insulation product and an insulation system incorporating such a product for insulating exterior walls, particularly masonry walls, that incorporates a wicking media to transport condensed water from the interface between the insulating product and the exterior wall to a more interior location where it can evaporate and/or a sorbent material for holding water. An active layer or layers comprising one or more of a wicking fabric, wicking media and sorbent material is provided on or near the exterior surface of the primarily insulating layer. When the insulating product is installed, the active layer will be closely adjacent and/or in contact with an inside surface of the exterior wall.  
         [0008]     The insulation product is preferably installed with a corresponding support element to form an insulation system. The support element will typically be provided along the lower edge of the insulation product and define a space between the insulation product and the floor. The support element may comprise several cooperating elements or structures and may, for example, include a baseboard portion to create a more finished appearance for the interior surface of the insulation system.  
         [0009]     This space defined by the insulation system may be used for routing an extension portion of the primary wicking material toward and/or into the interior space in order to increase the evaporation rate. Additional elements, such as vents, grills, fans, ducts, sorbent material, secondary wicking materials and heaters, may be included in or connected to the support element for further improving the performance of the insulation system.  
         [0010]     Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:  
         [0012]      FIGS. 1-4  are cross-sectional views of exemplary embodiments of an insulation product and insulation system according to the invention; and  
         [0013]      FIGS. 5-11  are cross-sectional views of portions of exemplary embodiments of an insulation system according to the invention. 
     
    
       [0014]     These drawings have been provided to assist in the understanding of the exemplary embodiments of the invention as described in more detail below and should not be construed as unduly limiting the invention. In particular, the relative spacing, positioning, sizing and dimensions of the various elements illustrated in the drawings are not drawn to scale and may have been exaggerated, reduced or otherwise modified for the purpose of improved clarity. Those of ordinary skill in the art will also appreciate that a range of alternative configurations have been omitted simply to improve the clarity and reduce the number of drawings.  
       DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS  
       [0015]     As shown in  FIG. 1 , the insulation system  100  will be installed adjacent an inside surface of an exterior wall  10  and above a floor  12 . The insulation system will include a primary insulating layer  14 , typically a mineral or glass fiber web and a wicking material layer  16 , provided on the outside surface of the insulating layer. As installed, the wicking material layer  16  will be adjacent to and will preferably have at least portions in contact with the inside surface of the exterior wall  10 . The wicking material layer  16  may be attached to the primary insulating layer  14  using any suitable method such as melt bonding or discontinuous adhesive layers.  
         [0016]     Thus positioned, the wicking material layer  16  will preferentially collect water as it is formed by the condensation of water vapor  18  that has diffused through the primary insulating layer  14  from the interior space  24 , typically a heated room, to a point near or at the cool, inside surface of the exterior wall  10  where the temperature falls below the dew point of the moisture content of the air. Similarly, the wicking material layer  16  will collect water  20  that diffuses or seeps through the masonry wall  10  from its outside surface, particularly for subsurface portions of the exterior wall that are not completely sealed. In addition to seepage, it will be appreciated that in those regions subject to periods of hot, humid weather, water vapor diffusing from the environment outside the exterior wall may condense as it reaches the cooler inside surface resulting from the air conditioning of the interior space  24 .  
         [0017]     The wicking material layer  16  is preferably a non-woven material that can be formed from a polymer or natural fiber. One suitable polymer for manufacturing the wicking material is rayon. Rayon fibers may be striated, or include channels, along the length of the fiber, which provide capillary channels within the individual fibers so the wicking action does not depend solely upon capillary action resulting from the channels formed between two adjacent fibers.  
         [0018]     In addition to rayon fibers, other polymeric fibers including polyester, nylon, polypropylene (PP) and polyethylene terephthalate (PET), may be manufactured or processed in a manner that will produce fibers including striations or channels on their surface. A number of fiber configurations have been developed that provide a plurality of surface channels for capillary transport of water and have been widely incorporated in active wear for improved comfort. These types of materials can be collectively referred to as capillary surface materials (CSM) and include so-called deep-grooved fibers that have high surface area per unit volume as a result of their complex cross-sectional configuration. The capillary material layer can be provided in different configurations including, for example, a non-woven film or a fine mesh configuration.  
         [0019]     As a result of gravity, the wicking material layer  16  will tend to transport any water  21  that condenses at the interface between the insulation product  100  and the exterior wall  10  downwardly along the interface and, near the lower edge of the insulation product, inwardly toward the interior space  24 . The portion of the wicking material layer  16  extending toward or into the interior space  24  will allow the water to evaporate as water vapor  26  into the interior space without dripping and without accumulating on the inside surface of the exterior wall  10 .  
         [0020]     There are several methods to form the wicking material which may be configured as a non-woven film and/or as a relatively fine mesh. The fibers can be laid down dry with an acrylic emulsion being applied to the fibers and then cured by heating or UV radiation exposure. Standard fiber binding emulsions such as acrylic or EVA (ethylene vinyl acetate) can be utilized.  
         [0021]     As illustrated in  FIG. 2 , in another embodiment of the invention the basic insulating material of  FIG. 1  may be modified to include a vapor retarding layer  30 . The presence of the vapor retarding layer  30  will tend to reduce the amount of moisture  18  from the moisture laden interior air diffusing through the primary insulating layer  14  by blocking a portion  18   a  of the vapor. By limiting the amount of moisture that can reach the cool inside surface of the exterior wall and/or adjacent materials, the vapor retarding layer can reduce the amount of condensation  21  that will be formed and removed through the wicking material layer  16 .  
         [0022]     As illustrated in  FIG. 3 , in another embodiment of the invention the basic insulating material of  FIG. 1  may be modified to include a layer of sorbent material  28 . The sorbent material layer  28  will tend to absorb water in excess of the volume that can be successfully transported through the wicking material layer  16  and reduce the likelihood of water being present at the inside surface of the exterior wall  10  even during periods of excessive condensation or seepage. The sorbent material layer  28  will cooperate with the wicking material layer  16  to provide a “damping” effect whereby periodic increases in the volume of water can be removed over a longer period of time and reduce the volume of the wicking layer required to remove the condensate from the interface region. The sorbent material layer  28  may be a separate premanufactured layer that is laminated to the primary insulating layer  14  along with the wicking material layer or may be applied to the primary insulating material as a liquid and then dried, cured and/or activated to form a sorbent surface region within the primary insulating layer.  
         [0023]     As illustrated in  FIG. 4 , depending on the volume of condensate and seepage that are anticipated for a particular installation, the wicking material layer  16  present in the insulation product illustrated in  FIG. 1  may be replaced by a layer of sorbent material  28 . Such an embodiment may be of particular utility for installations in which brief periods of high humidity are separated by longer periods of relatively low humidity. In such an environment, the sorbent material layer  28  will collect and hold the condensate formed from diffusing moisture  18  during periods of high humidity and allow the water vapor  23  to evaporate and diffuse back through the primary insulating layer  14  during periods of low humidity, thereby reducing or preventing the formation of water on the inside surface of the exterior wall  10 . A variety of sorbent materials may be used to form the sorbent material layer  28 , but will generally be characterized by their ability to absorb and hold at least about five times, and preferably at least about ten times, their weight in water.  
         [0024]     As illustrated in  FIG. 5 , the basic insulating product of  FIG. 1  may be incorporated with a support element to form an integrated insulating system. The support element may comprise one or more separate cooperating elements including a primary support element  32 , a fascia or trim element  32   a  and one or more connecting or holding elements  32   b  in order to simplify assembly, but will typically define a space into which an extending portion  16   a  of the wicking material layer  16  will extend toward the interior space  24 . The primary support element  32  and/or the trim element  32   a  may include openings such as vent holes  34  or a grill (not shown) to provide for evaporation of the water in the lower portion of the wicking material layer  16  into the interior space  24 .  
         [0025]     As illustrated in  FIG. 6 , the support element may incorporate a sorbent material  36  that is positioned in contact with the extending portion of the wicking material layer  16   a  to provide extra water capacity in the case of periodic increases in the volume of water being removed from the interface between the insulating product and the exterior wall.  
         [0026]     As illustrated in  FIG. 7 , the support element may also incorporate other elements such as a heating element  38  to assist in the evaporation of water from the extending portion  16   a  of the wicking material layer. As illustrated in  FIG. 8 , the support element may configured to provide additional space for holding a second wicking and/or absorbent material element  40  for increasing the evaporative area and thereby increase the volume of water that can be removed from the interface between the insulating product and the interior surface of the exterior wall. The support element may also define one or more passages  42  through which air or another gas may be forced by a fan or blower to increase the rate of evaporation from the surfaces of the second wicking element  40  and/or the extending portion  16   a  of the wicking material layer  16 .  
         [0027]     As illustrated in  FIGS. 8 and 9 , the primary support element  32  may be mounted on the inside surface of the exterior wall at a position above the floor,  FIG. 8 , or on or closely adjacent the floor,  FIG. 9 . The configuration illustrated in  FIG. 9  also allows direct attachment to the floor (not shown) and/or the inside surface of the exterior wall  10 . In either configuration, the trim or fascia portion  32   a  will typically be configured so that it can be attached, either permanently or removably, to the primary support element  32 , typically in a manner that will also engage at least the extending portion  16   a  of the wicking material. The trim element, whether incorporated in a unitary support element or, more typically, provided as a separate complementary element  32   a  that is subsequently attached to the primary support element  32 , will tend to be configured with a region that extends over a lower portion of the surface of the insulating product to provide a more finished and aesthetically pleasing appearance.  
         [0028]     As illustrated in  FIG. 10 , the support element may include a primary support element  32  that is fastened in some fashion to the inside surface of the wall  10  and/or the floor  12  (not shown). The primary support element may be configured to provide for some range of vertical adjustment during installation so as to provide a substantially level support surface onto which the lower surface of the insulating element may be placed during installation. As illustrated in  FIG. 10 , the insulating element may include both a primary insulating layer  14  and a wicking material layer  16 . The wicking material layer will typically include an extending portion  16   a  that will tend to drape over a forward portion of the primary support element  32 , or at least cover a portion of the top surface of the primary support element  32 , as the insulating element is set into place.  
         [0029]     The insulating system may then be completed by attaching a trim element  32   a  to the primary support element  32 . The trim element  32   a  may include one or more projections  32   b  or recesses (not shown) which will cooperate with complementary structures provided on the primary support element  32  for securing the trim element to the primary support element of the supporting element. As illustrated in  FIG. 10 , the projection  32   b  or other fastening structures provided on the trim element  32   a  and primary support element  32  may also be configured to engage and hold the extending portion  16   a  of the wicking material layer within the supporting element. As further illustrated in  FIG. 10 , the primary support element  32  and or the trim element  32   a  may be configured to define one or more raceways  44  in which cables, typically communication and networking cables  36  can be concealed and secured within the supporting element.  
         [0030]     As illustrated in  FIG. 11 , the primary support element  32  or the trim element  32   a  (not shown) may be provided with one or more elements or structures as illustrated in  FIGS. 5-8  for increasing the rate of evaporation of the water and/or condensate reaching the extending portion  16   a  of the wicking material layer  16 . In the particular embodiment illustrated in  FIG. 11 , the primary support element is provided with a secondary evaporative and/or wicking material  40  is configured with regions or structures  40   a  that will increase the effective surface area  40   a  or permeability (not shown). The secondary material  40  includes a contact region at which direct contact may be established between the primary portion (not shown) or, more typically, a region of the extending portion  16   a  of the wicking material layer when the insulating system is assembled. As a result of this contact, a portion of the water and/or condensate reaching the extending portion  16   a  of the wicking material layer will transfer to the secondary evaporative and/or wicking material  40  where it may be more readily evaporated as a result of the increased surface area provided by the fin structures  40   a . As will be appreciated, the secondary evaporative and/or wicking material  40  may assume a wide range of configurations within, and/or partially without, the support element housing. It will also be appreciated that the particular embodiments illustrated and discussed herein, while exemplary, are not to be considered limiting or exhaustive and that a wide variety of configurations may be utilized to achieve the desired functionality and/or adapt the insulating system for more and less challenging conditions.  
         [0031]     As also shown in  FIG. 11 , the trim element  32   a  may incorporate other structures such as a raceway  44  for communication or power cables  46 . The raceway may be configured to maintain a separation between the cables and the moisture remediation elements of the wall insulating system. The raceway may also be configured in a manner that will allow it to be opened to the interior space  24  for insertion and removal of cables  44  without requiring detaching of the trim element  32   a  from the primary support element (not shown).  
         [0032]     The principle and mode of operation of this invention have been described in its preferred embodiments. However, it should be noted that this invention may be practiced otherwise than as specifically illustrated and described without departing from its scope.