Patent Publication Number: US-2023160256-A1

Title: Adhesive-attached window glazing assembly, multi-glazed window assembly and method therefor

Description:
CLAIM OF PRIORITY/CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a Continuation-In-Part (CIP) Patent Application of previously-filed, currently-pending U.S. patent application Ser. No. 16/735,566 filed on Jan. 6, 2020, which is a Continuation-In-Part (CIP) Patent Application of previously-filed U.S. patent application Ser. No. 15/418,953 filed on Jan. 30, 2017. 
     The contents of both of the above-referenced, previously-filed patent applications, namely, U.S. patent application Ser. No. 16/735,566 filed on Jan. 6, 2020 and U.S. patent application Ser. No. 15/418,953 filed on Jan. 30, 2017, are incorporated herein in their entirety by reference. 
    
    
     STATEMENT OF GOVERNMENT INTERESTS 
     One or more inventions described herein was/were made with Government support under a Phase I, Small Business Innovation Research (SBIR) Award No. 2017-33610-26989 awarded by the United States Department of Agriculture (USDA). The Government may have certain rights in the invention. 
    
    
     FIELD OF THE INVENTION 
     The present invention is generally directed to a window glazing assembly and a method of installing a window glazing assembly to either an already-installed window unit or as a new construction window unit. The glazing assembly is adapted to provide one or more insulated airspaces to the window unit, thereby increasing the thermal insulating capabilities of the window. Retrofits offer an easy-to-install, do-it-yourself (DIY) application. New construction or replacement windows of the present invention offer the capacity for double, triple, quadruple or more thermal performance than existing windows. 
     BACKGROUND OF THE INVENTION 
     Many window units, e.g., windows in homes, buildings and/or commercial storefronts, lose or dissipate heat at an astounding rate. For instance, it is estimated that nearly $28 billion in annual energy used is wasted in that it, quite literally, goes out the window. This is true even though many windows, and in particular modern windows include double or multiple panes. 
     Adding insulating airspaces to the inside of the window unit or outside of the window unit can help maintain heat or keep heat in (when needed, for example in winter or cold climates) and restrict heat or keep heat out (when needed, for example in warmer or summer climates). While there are some assemblies that can be used to create insulating airspaces on windows, such assemblies are often quite complicated to install or are difficult to ensure a quality, airtight fit. In addition, some of the current solutions interfere with window operability, meaning that once installed, the additional components added to the window unit oftentimes interfere with or even prevent the window from being opened in the intended manner. 
     As a consequence, there is a need in the art for a window glazing assembly that is easy to install in retrofit and new construction applications that can provide a simple way to convert a single or multiple glazed window unit into a further glazed window unit, providing additional window glazing layers and insulating airspaces. It would also be beneficial if the window unit would maintain its original operability, i.e., opening and closing of the window unit is not impeded or substantially impeded by the glazing assembly. 
     Further advantages of the proposed glazing assembly include a simple DIY installation. High and affordable performance is desirable, for example, providing insulation with an R-value in the range of R-6 to R-14 or better. In this manner, the R-value of a window unit with the proposed glazing assembly installed may be better than some opaque walls. 
     SUMMARY OF THE INVENTION 
     The present invention of at least one embodiment is generally directed to a window glazing assembly that can convert an existing or already-installed window to a multi-pane or multi-glazed window unit, providing enhanced insulation capabilities. Other embodiments may include a multi-glazed window assembly for use in new construction or replacement windows. 
     In particular, the glazing assembly and/or multi-glazed window assembly of at least one embodiment may include an attachment assembly and one or more glazing panels or layers. The attachment assembly may be in the form of a peel-and-stick double sided tape that allows easy attachment of the glazing panel(s) or layer(s) to a selected portion of the window unit, including, but not limited to the window sash or glass window pane, itself. Some embodiments further include a spacer assembly comprising a plurality of spacer bars that may be individually or separately installed, e.g., one by one, around the perimeter of the window (again, to the window sash or glass window pane, itself). The added glazing layer(s) can then be secured or adhered to the spacer assembly, for example, around the perimeter of the glazing layer(s). Some embodiments may include additional or intermediate glazing layers, providing additional insulating airspaces and enhanced performance. 
     Typical existing single pane wood sashes often have a depth of about 0.5 inches to 1 inch between the sash face and the glass window pane. Applying a clear, double-sided tape or other attachment assembly to the perimeter of the window sash, and then a clear acrylic glazing layer to the tape creates an insulating airspace which can cut single pane thermal loss and gain in half. 
     Desiccant faced tape or other like drying agents or substances can be exposed to the inside of the created or insulated airspace in order to control condensation, fogging and/or moisture therein. An additional insulating airspace can be created using a spacer assembly (e.g., ⅝×⅝ PVC trim) that can be supplied cut-to-measure for easy peel-and-stick application around the perimeter of the sash, glass or other portion(s) of the window unit. The glazing layer can then be applied to the spacer assembly to create the insulating airspace. It should be noted that the glazing layer(s) can include a sheet of transparent or translucent acrylic, although other embodiments may use other materials, such as glass, etc. As provided herein, the glazing layer(s) can be tinted, e.g., with a window tint film, to provide additional heat resistance or shielding. In further embodiments, the glazing layer(s) may be hurricane wind/impact resistant in order to meet certain building code and other requirements and regulations. 
     It should also be noted that the present invention may also be applied to new construction or replacement window units. 
     Furthermore, a thick or wide spacer assembly (e.g., ⅝ inch×1.5 inch PVC trim) may be used or attached to inner or outer glazing layers with one or more intermediate glazing layers within the same spacer assembly or frame. This creates further insulating airspaces (e.g. three) when two glazing layers are spaced 0.5 inches apart. When applied to a window unit, the multi-glazing assembly creates even more enhanced insulating capabilities (e.g., with an R-value of R-5 or better). 
     In new construction, the inner and outer glazing layers or panels may act as structural diaphragms between the spacer assembly to create a stress-skin panel capable of resisting structural loads. The load-bearing capacity is aided by the additional structural diaphragm created by the intermediate glazing layers through their attachment to the perimeter of the spacer assembly, which effectively acts as both the sash and frame for the window unit. These multi-layered clear-skinned structural diaphragms avoid the use of headers and potentially carry floor or roof loads without added structure. The diaphragms further add to structural lateral resistance as a sheer panel when connected to other structural elements. 
     These and other objects, features and advantages of the present invention will become more apparent when the drawings as well as the detailed description are taken into consideration. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an elevation view of the inside of an exemplary window unit. 
         FIG.  2    is a partial cut-away and exploded view of the glazing assembly as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  3    is an elevation view of a window unit with the glazing assembly of at least one embodiment installed thereon. 
         FIG.  4    is a side cut-away view of a window unit with the glazing assembly of at least one embodiment installed on one side thereof. 
         FIG.  5    is an exploded view illustrating the spacer assembly and glazing panel as disclosed in accordance with yet another embodiment of the present invention. 
         FIG.  6    is a perspective, exploded view of the glazing assembly as disclosed in accordance with at least one embodiment herein. 
         FIG.  7    is a side cut-away view of a window unit with the glazing assembly of one embodiment installed on one side thereof. 
         FIG.  8    is a plan view of a storefront window with the glazing assembly of at least one embodiment installed thereon and illustrated in a partially exploded fashion. 
         FIG.  9    is a side, sectional and at least partially exploded view of the multi-glazed window assembly as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  10    is a side, sectional and at least partially exploded view of the multi-glazed window assembly as disclosed in accordance with another embodiment of the present invention. 
         FIG.  11    is a side, sectional, cut-away and at least partially exploded view of the multi-glazed window assembly as disclosed in accordance with another embodiment of the present invention. 
         FIG.  12    is a side, sectional, cut-away and at least partially exploded view of the multi-glazed window assembly as disclosed in accordance with yet another embodiment of the present invention. 
         FIG.  13    is a perspective end view of a desiccant-filled conduit as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  14    is a side, sectional and at least partially exploded view of the multi-glazed window assembly as disclosed in accordance with another embodiment of the present invention. 
         FIG.  15    is a high level flow chart illustrating the method as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  16 A  is a perspective view of the window assembly as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  16 B  is a cut-away partially exploded view of the window assembly illustrated in  FIG.  16 A . 
         FIG.  16 C  is a cut-away, partially exploded view of the window assembly illustrated in  FIG.  16 A  and installed within a window opening as a lift-out egress window unit. 
         FIG.  16 D  is a cut-away, partially exploded view of the window assembly illustrated in  FIG.  16 A  showing exemplary summer and winter sun rays. 
         FIG.  16 E  is an exterior to interior view of the window opening showing the second stop and external framing structures as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  17    is a plan view of yet another embodiment of the window assembly of the present invention with at least one diffusion grid installed therein. 
         FIG.  18    is a partial cut-away view of a retrofit application of the window assembly as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  19    is a cut-away view of a window or sunlight assembly as disclosed in accordance with at least one embodiment of the present invention. 
         FIG.  20 A  is a sectional cut-away view of yet another embodiment of the multi-glazed window assembly as disclosed in accordance with at least one embodiment showing two glazing layers, one spacer assembly and one insulating airspace. 
         FIG.  20 B  is a sectional cut-away view of another embodiment of the multi-glazed window assembly as disclosed in accordance with at least one embodiment showing three glazing layers, two spacer assemblies and two insulating airspaces. 
         FIG.  20 C  is a sectional cut-away and exploded view of another embodiment of the multi-glazed window assembly as disclosed in accordance with at least one embodiment. 
         FIG.  21    is a sectional cut-away view of another embodiment of the multi-glazed window assembly as disclosed in accordance with at least one embodiment showing a thermal storage medium filling material disposed within at least one of the spacer assemblies. 
         FIG.  22 A  is a sectional cut-away view of another embodiment of the multi-glazed window assembly as disclosed in accordance with at least one embodiment showing a lighting assembly disposed within the insulating airspace. 
         FIG.  22 B  is a sectional cut-away view of another embodiment of the multi-glazed window assembly as disclosed in accordance with at least one embodiment showing a lighting assembly disposed within the insulating airspace and within the clear tube of the spacer assembly. 
     
    
    
     Like reference numerals refer to like parts throughout the several views of the drawings provided herein. 
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in the accompanying drawings, at least one embodiment of the present invention is directed to a window glazing assembly, as generally referenced as  10 , for example, in  FIG.  2   . Other embodiments include a multi-glazed window assembly  80  (e.g., as shown in  FIGS.  9 - 12   , and a method of installing a window glazing assembly, as generally referenced as  100  in  FIG.  15   . In particular, the window glazing assembly  10  of at least one embodiment of the present invention comprises a retrofit assembly that can be easily applied or installed to existing or already-installed window units  1 . However, it is contemplated that some embodiments of the present invention, and in particular, the multi-glazed window assembly  80  and method  100  can be applied as new construction or as a replacement window. 
     In any event, the window glazing assembly  10  and multi-glazed window assembly  80  of certain embodiments of the present invention are structured to provide or otherwise create a dead airspace, for example, between the window glazing assembly  10  and the existing window pane(s)  5  of a window unit  1 , or between inner and outer glazing layers, to increase or provide enhanced insulation on the window unit  1 . For example, certain embodiments of the present invention can be used to reduce thermal loss (e.g. in cold climates) and/or reduce thermal gain (e.g., in warm climates). 
     For instance, with reference to the exemplary window unit  1  represented in  FIG.  1   , a window unit  1  may include a frame assembly  2  and one or more window panes  5 . The window frame  2  may include an outer frame unit, generally represented as  3 , and a window sash, generally represented as  4 . Particularly, the outer frame unit  3  of the window unit  1  may include the framework that surrounds the entire window unit  1 , and may include, for example, the window head unit, jamb, sill, etc. The head unit is generally the main horizontal part of the top of the window frame, the sill is the main horizontal part of the bottom of the window frame, and the jamb are the main vertical parts forming the sides of the window frame  2 . The window sash  4  is generally considered the inner portions of the frame  2  that hold or at least partially retain the window pane(s)  5 . Specifically, the window sash  4  often holds or retains the glass portion of the window unit  1  and is made up of horizontal and vertical frame units. Oftentimes, depending on the specific construction of the window unit  1 , the sash  4  may move, for example, up and down, in and out, side-to-side, etc. in order to open and close the window. With reference to the example shown in  FIG.  1   , a sash lock  6  locks and unlocks the bottom sash  4 , allowing the bottom sash  4  to move up and down, thereby opening and closing the window unit  1 . Of course, there any numerous other window units  1  with different constructions, layouts, moving parts, non-moving parts, etc. that can be used in accordance with the various embodiments of the present invention, and it should be understood that the example window unit  1  shown in  FIG.  1    is for illustrative or exemplary purposes only. 
     With reference now to the perspective, exploded and cut-away illustration of  FIG.  2   , at least a portion of the window glazing assembly  10  of at least one embodiment is shown. Specifically, the window glazing assembly  10  may include an attachment assembly  20  and one or more glazing panels or layers  30 . For instance, the attachment assembly  20  is structured and/or adapted to easily attach the glazing layer(s)  30  to the window unit  1 , for example, in an overlying or covering relation thereto. In some embodiments, and as shown in  FIG.  2   , for example, the attachment assembly may include one or more strips or portions of an adhesive tape that can be applied to the window unit  1 , and upon which the glazing layer(s)  30  can also be attached or adhered. In this manner, the attachment assembly  20 , and in particular, the adhesive tape of at least one embodiment may include a peel-and-stick type of tape with double-sided adhesive surfaces to enable easy application or attachment to the window unit  1  (e.g., to the window sash and/or glass panes) and to the glazing layers  30 . 
     For example, still referring to  FIG.  2   , the attachment assembly  20 , and in particular the attachment tape may include a peel-and-stick double-sided strip of tape such that a layer  22 ,  24  may be peeled off of one or both sides of the tape to reveal the adhesive surface thereof. One of the adhesive surfaces may be adhered to the window unit  1 , for example, at or around the sash  4 , whereas the other adhesive surface can be adhered to the inside of the glazing layer  30 . 
     Particularly, the attachment assembly, e.g., the peel-and-stick adhesive strips of one embodiment, may be adhered to a portion of the window unit  1 , for example, either around the sash  4 , another portion of the window frame  2 , and/or in some cases, the window pane(s) itself (particularly in commercial, storefront applications). The strips or attachment assembly  20  may be attached to create a substantially continuous perimeter or otherwise be secured to the window unit  1  in a substantially continuous, end-to-end manner, as generally represented in  FIG.  3   , for example. For instance, in the embodiment where the attachment assembly  20  includes a plurality of strips of adhesive tape, the strips can be secured or adhered one by one in an end-to-end or substantially continuous manner in order to create a substantially continuous seal around the perimeter of the glazing layer  30 . This can restrict any unwanted moisture, air, etc. from entering the space between the glazing layer(s)  30  and the existing window pane  5 . 
     Furthermore, as shown in  FIGS.  3  and  4   , for example, the attachment assembly  20 , and in particular, the peel-and-stick double-sided adhesive tape of at least one embodiment may be secured at, near or proximate an outer perimeter edge  32  of the glazing layer  30 . In this regard, the outer perimeter edge  32  of the glazing layer  30  may be adhered or secured to the window unit  1  via the attachment assembly  20  of at least one embodiment providing a perimeter and edge seal substantially continuously around the glazing layer  30 . 
     With reference now to  FIG.  4   , a side or cut-away/sectional view is shown with the window glazing assembly  10  installed on one side of a window unit  1 . It should be noted that the assembly  10  can be installed on either or both sides, e.g., the inside and/or the outside, of the window unit  1 . Particularly, in some applications, the glazing assembly  10  may be installed outside, for example, on an upper portion of a window unit  1 , where the lower portion of the window unit  1  slides or moves up in order to open/close the window. This allows the assembly  10  to be installed while maintaining window operability, i.e., maintaining the ability to open/close the window as designed. Other applications (e.g., inside, outside, or both) may differ depending on the style, size and shape of the particular window unit  1 . 
     In any event, still referring to  FIG.  4   , the assembly  10  creates an airspace, such as an insulated dead airspace  12  between the window pane  5  and the glazing layer  30 . The airspace  12  may be approximately ¼ of an inch to ¾ of an inch thick (measured from the window pane  5  to the glazing layer  30 ), although other sizes and dimensions are contemplated within the full spirit and scope of the present invention. In the embodiment shown in  FIG.  4   , the attachment assembly is secured to the window sash  4  and the glazing layer  30  is secured or adhered thereto. It should be noted that additional glazing layer(s)  30  may be layered or secured to the inside or outside of the window unit  1  creating additional layered and separated insulated airspaces  12 . 
     In yet another embodiment, as shown in  FIG.  5   , the assembly  10  of at least one embodiment includes at least one spacer assembly  40  comprising a plurality of spacer bars  42 ,  44 ,  46 . The spacer assembly  40  is adapted to secure or adhere to the window unit  1 , wherein the glazing layer(s)  30  is secured or adhered to the spacer assembly  40 . This spaces the glazing layer(s)  30  from the window unit  1 . For example, in some instances, depending on the particular construction or design of the window unit  1 , the spacer assembly  40  may be needed in order to space the glazing layer  30  from the window unit  1 , for example, maintaining window operability when applied to the sash. In some cases, and particularly but not limited to some commercial storefront applications, the spacer assembly  40  may be adhered or secured to the window pane(s)  5  itself. For instance, some windows may not have a sash  4  or frame  2  that can be easily used or that can be used to attach the glazing layer(s)  30  to. In such a case, the spacer assembly  40  may be used to create a flat surface upon which the glazing layer(s)  30  can be attached, or it can create a spaced relation between the window pane  5  and the glazing layer  30  for the insulated airspace  12 . 
     In some cases, the spacer assembly  40  or spacer bars  42 ,  44 ,  46  may be substantially rigid or rigid and, as an example, can be constructed of polyvinyl chloride (PVC) trim material, wood, metal, etc. For example, the various spacer bars  42 ,  44 ,  46  of at least one exemplary embodiment may include ⅝ inch×⅝ inch PVC trim material that can be cut-to-measure and easily applied to the window unit  1 . Of course, other sizes, dimensions and materials are contemplated within the full spirit and scope of the present invention. 
     For instance, in at least one embodiment, the spacer assembly  40  may be adhered to the window unit  1  via a peel-and-stick adhesive tape  20 . The adhesive tape may be already secured to one side of the spacer assembly  40 , or it may be separate such that the user or installer may be able to adhere to the tape or attachment assembly  20  to the spacer assembly  40  and the window unit  1 . Accordingly, in such an embodiment, the attachment assembly  20  used to secure the spacer assembly to the window unit may include a peel-and-stick double-sided adhesive tape that can be secured around the perimeter of the spacer assembly  40  between the spacer assembly  40  and the window unit  1  (e.g., on the sash  4  or window pane  5 ) to provide an air-tight and/or weather-tight seal. 
     An additional attachment assembly  20 , such as additional peel-and-stick double-sided tape may be adhered or secured to the other or outside surface of the spacer assembly  40  in order to allow the glazing layer(s)  30  to be secured or adhered thereto. Accordingly, the spacer assembly  40  may be secured between the window unit  1  and the glazing layer(s)  30  to create the insulated airspace  12 , as shown in  FIGS.  5  and  6   , for example. 
     Referring to  FIG.  5   , the spacer assembly  40  of at least one embodiment includes a top spacer bar  42 , a bottom spacer bar  44  and two side spacer bars  46 . For instance, in one embodiment, the top spacer bar  42  may include opposite lateral ends  43  that extend to or align with outer lateral edges  47  of the side spacer bars  46 . In this regard, there are no vertical joints between the top spacer bar  42  and the side spacer bars  46 —only the two horizontal joints. This offers structural rigidity in the top spacer bar  42 , which can be used as a structural load bearing support in some implementations. Still referring to  FIG.  5   , the bottom spacer bar  44  of at least one embodiment may fit between inner side edges  45  of the side spacer bars  46  such that there are no vertical joints between the bottom spacer bar  44  and the side spacer bars  46 —only the vertical joints. 
     Furthermore, in at least one embodiment, the inner edge(s) of the spacer assembly  40 , represented as  41 ,  45 , and  49  in  FIG.  5    may substantially align with or be adjacent the inner edge of the sash  4 , represented as  7  in  FIG.  6   . 
     Other installation techniques and alignment of the spacer bars or spacer assembly  40  may be implemented in accordance with the various embodiments described herein. 
     With reference now to the cut-away or sectional view of  FIG.  7   , an exemplary installation of the glazing assembly  10  on one side of a window unit  1  using a spacer assembly  40  is shown. In this example, window unit  1  includes a double pane window, such that the window unit  1  already includes two (2) panes  5 . In any event, the spacer assembly  40  is shown as being attached to the inner glazing layer  30  via an attachment assembly  20 , such as a peel-and-stick double-sided adhesive tape. Similarly, the outer glazing layer  35  is shown as being attached to the spacer assembly  40  via an additional attachment assembly  20 , which again, may be a peel-and-stick double-sided adhesive tape. Other attachment assemblies structured to facilitate the practice of the present invention in the intended manner are contemplated. Either way, the spacer assembly  40  facilitates in the creation of an insulated airspace  12 , in this example, between an inner glazing layer  30  and an outer glazing layer  35 , with a weather-resistant perimeter seal via the attachment assemblies  20 . It should be noted, however, that the attachment assembly  20  may be secured directly to the window unit  1 , such as at the sash  4 , such that the inner glazing layer  30  shown in  FIG.  5    may not be included. In such a case, the spacer assembly  40  facilitates in the creation of an insulated airspace  12  between the window pane  5  and the outer glazing layer  35 . 
     In some embodiments, the spacer assembly  40  and the glazing layer(s)  30  may be constructed of materials with similar coefficients of thermal expansion. For example, in some embodiments the spacer assembly  40  may be constructed of a PVC type of material and the glazing layer(s)  30  may be constructed of an acrylic, plastic or glass. In some implementations, the coefficients of thermal expansion for the material selected for the spacer assembly  40  may be substantially the same as the coefficient of thermal expansion for the material selected for the glazing layer(s)  30 , and in particular, the coefficients of thermal expansion may be between 1 and 2 times one another for the different materials or for the spacer assembly  40  and the glazing layer(s)  30 . 
     It should also be noted that the glazing layer(s)  30  of some embodiments may be tinted, for example, it may be coated with a window film comprising a tint that is adapted to restrict the passage of sunlight or UV rays there through. Some embodiments of the glazing layer(s)  30  may also be constructed of a hurricane wind or impact resistant material. In this manner, the assembly  10  of the present invention may also serve to provide thermal loss and gain resistance via the tint or window film and/or impact resistance via the material selected for the glazing layer  30 . 
     Further embodiments may also include a desiccant or other drying agent disposed on the inside of the airspace  12  or otherwise exposed to the inside of the airspace  12  in order to control moisture or condensation with the airspace  12 . For example, as shown in  FIGS.  6  and  7   , in at least one embodiment, a desiccant tape  60  or other drying agent may be adhered to the inside-facing surface(s)  41 ,  45 ,  49  of the spacer assembly  40  such that a desiccant or drying agent surface  62  of the tape  60  faces inward toward the airspace  12 , and the adhesive surface  64  secures to the spacer assembly  40 . Although, the desiccant tape  60  is shown as being attached to the lower or bottom bar  44 , the desiccant tape  60  may be adhered or attached to any one or more of the bars  42 ,  44 ,  46  of the spacer assembly  60 . It should also be noted that the desiccant tape  60  may be adhered to the window unit  1  (such as the sash  2 , frame  4 , or window pane  5 ) or to the glazing panel  30 , so long as the desiccant surface  62  is exposed to the airspace  12  created by the assembly  10  in order to control moisture, condensation, etc. therein. Other embodiments may use other condensation or moisture control substances or devices, and as such, the present invention is not limited to use of desiccant tape. For example, other types of tape, packets, dry packs, silica gel devices/packs, etc. can be used. 
     Other embodiments may include one or more modular ventilated desiccant (or other drying agent) filled conduits or tubes  50  that may be adhered or attached to the inside face of the sash or spacer bar(s), for example, for condensation control. In particular, with reference to  FIGS.  13  and  14   , the conduit(s)  50  may include ventilation sections  51 , for instance, at the ends or along the length thereof, for allowing the desiccant substance or other drying agent disposed therein to be exposed to surrounding air or environment. In this case, the conduit(s)  50  may be disposed within the insulated airspace(s)  12 , for example, by being secured to a portion of the spacer assembly  40 , the inside-facing surface of one or more of the layers  30 , etc. In yet another embodiment, a desiccant substance (or other drying agent) may be embedded directly in the spacer bar(s) or spacer assembly  40 , for instance, in drilled or other made holes or channels. The holes or channels may include a perforated or ventilated cover in order to allow ventilation between the desiccant substance and the insulating airspace  12 . 
     In some cases, the conduit(s)  50  may include or otherwise contain a phase change or heat storage material (PCM), such as, but not limited to a paraffin wax material, in order to moderate the temperature between the inside and outside of the window assembly. For example, a conduit, such as a cross-linked polyethylene pipe, may be disposed between the glazing layers (e.g., around an inside perimeter of one of the glazing layers within the insulated airspace, or in some cases, through the glazing layers. In some cases, the spacer assembly may include a hollow tube filled with or at least partially containing a PCM material. 
     It should also be noted that the glazing layer(s)  30  and/or spacer assemblies  40  may be constructed in virtually any shape and size, including curves, and thus should not be deemed limited to the square or rectangular shapes shown in the Figures. For example, a curved spacer assembly  40  and/or glazing layer  30  can be used to create airspaces  12  for barrel vaulted skylights, greenhouses, light transmitting panels, and windows with curves and other unique shapes and sizes. For instance, the spacer bar(s) may be bent along the thickness, along with the attachment assembly or adhesive strips and the acrylic (or other) glazing layer(s) to match the curves or other dimensions of virtually any shape and size window, such as skylights, greenhouses, light transmitting panels, etc. 
     Referring now to  FIG.  8   , a plan and partially exploded view of the glazing assembly  10  is shown installed on an aluminum frame  2  of a commercial storefront, as an example, with a single layer glass pane  5  towards the exterior. Insulating airspaces  12  are created by applying peel-and-stick attachment tape  20  to the frame  2  and/or a plurality of spacer bars or spacer assemblies  40 . One or more glazing layers  30  can be applied or secured to the spacer assemblies  40 , for example, via attachment tape  20 , fitted channels  90 , etc. Furthermore, as provided herein, desiccant tape  60  or other like drying agents tubes, conduits or channels may be exposed to the inside of the airspaces  12 . 
     With reference now to  FIGS.  9  through  12   , the window glazing assembly includes a multi-glazed window assembly, referenced as  80 , which may be used for new construction, replacement windows, etc. In particular, the assembly  80  of at least one embodiment includes an inner and outer glazing layers  130 ,  230 , and in some embodiments, one or more intermediate glazing layers  330 . Specifically, the inner glazing layer  130  may be facing, exposed to, or disposed on the inside of the building, structure or home, whereas the outer glazing layer  230  may be facing, exposed to, or disposed on the outside of the building structure or home. 
     Specifically, the embodiment illustrated in  FIG.  9    includes an inner glazing layer  130 , an outer glazing layer  230  and two intermediate glazing layers  330 . The inner and outer glazing layers  130  and  230  are secured to a spacer assembly  40  via an attachment assembly  20 , such as, for example, peel-and-stick double-sided adhesive tape, although other attachment assemblies or mechanisms may be used. As before, the tape may be secured around the outer edges of the glazing layers  130 ,  230  to provide a continuous edge or perimeter seal. 
     The intermediate glazing layer(s)  330  may be secured to the same spacer assembly  40 . For example, in the embodiment illustrated in  FIG.  9   , the intermediate glazing layers  330  are secured at one end (e.g., the bottom end) to the corresponding (e.g. bottom) bar of the spacer assembly  40  via cooperative slots, channels or kerfs  90  cut into the surface of the spacer bar or spacer assembly  40 . At the other end (e.g., top end), the intermediate glazing layers  330  are secured to the spacer assembly  40  via double-sided tape. Other attachment mechanisms, devices, or means are contemplated. 
     Also, as shown in  FIG.  9   , a shade assembly, generally referenced as  95  is shown as being disposed between two of the glazing layers and within the insulting airspace  12  created thereby. In the illustration, the shading assembly  95  includes a plurality of spaced louvers that can be used to control an amount of light passing through the window assembly  80 . The shade assembly may be fixed or movable and may be secured to the glazing layers and/or to the spacer assembly  40 . 
       FIG.  10    illustrates a further embodiment of the multi-glazed window assembly  80 . In particular, inner and outer glazing layers  130 ,  230  are adhered to a spacer assembly  40  via an attachment assembly  20 , such as double-sided attachment or adhesive tape around its perimeter. A plurality of intermediate glazing layers  330  are secured in slots or channels along the inside of the spacer bars of the spacer assembly  40  to create seven (7) separate insulating airspaces  12 . This can create a total thermal resistance or R-value of R-14 or higher. It should also be noted that, the inner and outer glazing layers  130 ,  230  of this installation may act as structural diaphragms between the spacer assembly  40  to create a stress-skin panel capable of resisting structural loads. The load-bearing capacity is aided by the additional structural diaphragm created by the intermediate glazing layers  330  through their attachment to the spacer assembly  40 , which, in some installations, can act as both the sash and frame for the window unit. These multi-layered clear-skinned structural diaphragms may avoid the use of headers and potentially carry floor or roof loads without added structure. The diaphragms further add to structural lateral resistance as a sheer panel when connected to other structural elements. 
       FIG.  11    illustrates another embodiment with intermediate spacers  140  secured or disposed between some or all of the intermediate glazing layers  330  in order to facilitate connection or attachment of the intermediate glazing layer  330 . For instance, the intermediate spacers  140  may be secured to the inner face of the spacer assembly  40 , providing one or more attachment surfaces for the intermediate glazing layers  330  to attach, as shown. The intermediate spacers  140  may be secured or attached to the spacer assembly  40  via an attachment assembly  20 , such as double-sided tape or other attachment methods or devices. Similarly, the intermediate glazing layers  330  may be secured to the intermediate spacers  140  via an attachment assembly  20 , such as double-sided tape or other methods or devices. 
       FIG.  12    illustrates corner edge treatments or covers  73  (e.g., angle section trim) which may be disposed over one or more of the outer exposed corners of the glazing layer(s)  130 ,  230  in order to create a finished appearance and, in some cases, additional weather protection, particularly for externally installed assemblies  10 . 
     Referring again to  FIG.  14   , at least one embodiment may further include a conduit  75 , such as a ventilation tube or conduit, that passes through one or more of the plurality of glazing layers and provide airflow there through. Particularly, in one embodiment, the conduit  75  or ventilation tube may pass through each of the glazing layers  130 ,  230 ,  330  in order to provide ventilation and/or airflow there through, such as, from outside of the building, through the assembly, and into the inside of the building. 
     Still referring to  FIG.  14   , at least one embodiment may further include a heat collection and transfer conduit  74 , such as a radiant heat tube, that is disposed within at least one of the airspaces  12 . In the embodiment shown, the heat collection and transfer conduit  74  is attached to the spacer assembly  40  at opposite ends thereof, although other attachments or securement of the conduit  74  is contemplated. In any event, the conduit  74  of at least one embodiment may include a heat transfer fluid or other like substance disposed therein for providing radiant heat collection and transfer. 
     With reference now to  FIG.  15   , the present invention further comprises a method of installing a glazing assembly  10  to an already-installed window unit or to a new construction window unit. The method, generally referenced as  100 , includes attaching a spacer assembly to a window unit  102 . As provided above, the spacer assembly  40  of at least one embodiment may include a plurality of separate, rigid spacer bars  42 ,  44 ,  46 . In one embodiment of the method  100 , the individual bars  42 ,  44 ,  46  may be adhered to the window unit, one-by-one, to create the final spacer assembly  40 . Specifically, rather than assembling a spacer assembly first, and the attaching that assembly to the window unit, the spacer bars  42 ,  44 ,  46  may be individually attached to the window unit (e.g., to the sash  4 , the window pane  5  or other portions of the frame  2 ). 
     As above, in one embodiment, the attachment assembly includes a peel-and-stick double-sided adhesive tape. In this manner, the tape or attachment assembly  20  may be adhered to the spacer assembly  40  or the individual bars thereof, which can then be adhered to the window unit  1 . Alternatively, the attachment assembly  20  may first be adhered to the window unit  1 , and then the spacer assembly  40 , and in particular, the individual bars, may be adhered thereto. Either way, the individual or one-by-one placement or installation of the bars  42 ,  44 ,  46  allows the spacer assembly  40  to obtain a tight, secure and weather-resistant seal around its entire perimeter. 
     Furthermore, as shown at  104 , the method  100  may also include aligning the inner edge of the spacer assembly  40 , and in particular, the individual bars  42 ,  44 ,  46  thereof, to an inner edge of the window frame  2 , such as an inner edge of a window sash  2 . 
     Some embodiments also include adhering or installing a desiccant tape or other moisture control device, as shown at  106 . For example, the moisture control device or desiccant tape may be adhered to an inside edge of the spacer assembly  40 , to the window unit  1 , itself, or to any other location, so long as the desiccant portion or other dry material portion is exposed to the inner airspace created by the glazing assembly  10  of the present invention. 
     Accordingly, as shown at  108 , the method  100  further includes attaching the one or more glazing layers  30  to the window unit  1  or to the spacer assembly  40  (if used). The glazing panel  30  may be adhered to the window unit  1  or spacer assembly  40  via peel-and-stick tape or other attachment assembly  20  that will create an airtight and weather-resistant seal, preferably around the perimeter of the glazing layer  30 . 
     Furthermore, it should also be noted that some embodiments of the present invention, as shown in  FIG.  10   , may include additional or intermediate glazing layers  330 , for example, between the window pane  5  and the glazing panel  30  in retrofit situations, or between inner and outer glazing layers  30  in the case of new construction and replacement windows. In this manner, the present invention may create a number of different, individual and spaced airspaces via intermediate spaced glazing layers installed on the inside and/or outside of the window unit  1  or between inner and outer glazing layers  30 . This may be accomplished in a number of different ways. For example, in one embodiment, the spacer bars  42 ,  44 ,  46  may be thicker (e.g., in the range of 1 inch to 7.25 inches) wide with one or more glazing layers  30  disposed along the width thereof creating a multi-layered glazing assembly with an extremely high thermal resistance and energy efficiency. Particularly, one or more of the intermediate glazing layers can be adhered around its perimeter to the inner face of an intermediate spacer bar  140  (e.g., via glue, tape, etc.) In another embodiment, the spacer bar(s) may include routed slots, channels or kerfs on the inner face thereof for receiving the outer perimeter edge of the intermediate glazing layer(s). In this manner, a plurality of glazing layers may be installed or attached to a spacer assembly creating a plurality of insulated airspaces via a single glazing assembly. In some applications, each ½ inch of insulating airspace, for example, as created by the intermediate glazing layer(s) and/or outer glazing layer(s), forms an R-2 (or more) thermal resistance. For example, an application with three (3) insulating airspaces, created by using three glazing layers, forms an R-6 (or more) thermal resistance. 
     Moreover, in some embodiments, tinting or other window film or overlay, including a diffusion grid, may be used to control or optimize energy or heat loss/gain depending on various factors, including, but not limited to the particular climate zone in which the window is located in the structure, the compass orientation of the window (e.g., does it face north, south, east or west), the exterior shading condition proximate the window, etc. Particularly, tinted glazing panels may be positioned or located toward the exterior of the window unit in a cooling degree-day-dominated climate, in order to maximize heat rejection. Whereas, tinted glazing layers may be positioned or located toward the interior of the window unit in heating degree-day-dominated climates, thereby balancing desirable winter heat gain with summer heat rejection. This will cause light to be absorbed and the reradiated as heat from the tinted glazing panels work in favor of the dominate season. 
     Additionally, in some embodiments, one or more of the glazing layers, such as the inner or outer glazing layers  130 ,  230 , for example, may be at least partially covered with a film or sheet (e.g., a static film covering) that provides sacrificial and easily replaceable UV and scratch resistance. 
     With reference now to  FIGS.  16 A,  16 B,  16 C and  16 D  yet another embodiment of the multi-glazed window assembly of the present invention is illustrated. In particular, the window assembly may include a perimeter sash assembly  340 , or otherwise a perimeter or first spacer assembly constructed of or comprising a bottom perimeter sash  342 , a top perimeter sash  344 , and side perimeters sashes, such as left side perimeter sash  346  and right side perimeter sash  348 . It should be noted that the perimeter sash assembly  340  of at least one embodiment functions as the window sash, as well as at least a portion of the spacer assembly described herein and used to space a plurality of glazing layers. The perimeter sash assembly  340  may be constructed of wood, PVC, plastic, composite materials, metal, etc. 
     As will become apparent herein, and with reference to the Figures, each of the perimeter sashes  342 ,  344 ,  346 ,  348  of the perimeter sash assembly  340  includes an enclosed or inner surface  340 C spanning between a corresponding first (or interior) face  340 A and a second (or exterior) face  340 B. The enclosed surface  340 C of at least one embodiment may be used to define the width of the perimeter sash assembly  340 , which can be measured between a first face  340 A and a corresponding second face  340 B of a common one of the plurality of perimeter sashes  342 ,  344 ,  346 ,  348 . 
     Furthermore, an inner spacer assembly  440  may also be included, and is similar to the intermediate spacers  140  disclosed above in accordance with at least one embodiment, and thus may be rigid and/or constructed of wood, PVC, plastic, composite materials, metal, etc. In particular, inner spacer assembly  440  may include at least one bottom spacer  442 , at least one top spacer  444 , and at least two side spacers, such as a left side spacer  446  and right side spacer  448 . 
     Each of the spacers  442 ,  444 ,  446 ,  448  of the spacer assembly  440  includes an enclosed first face  440 A and a second face  440 B, opposite one another, as shown in the Figures. The width of the spacer assembly  440  may be measured between a first face  440 A and a corresponding second face  440 B of a common one of the plurality of spacers  442 ,  444 ,  446 ,  448 . With reference to the cut away views of  FIGS.  16 B,  16 C and  16 D , the spacer assembly  440  is, in at least one embodiment, separate from the perimeter sash assembly  340  and is attached or fixed to the enclosed surface  340 C of the perimeter sash assembly  340  and the spacer assembly  440  includes a width that is less than the width of the perimeter sash assembly. 
     Moreover, an inner glazing layer  130  is attached to the first surface(s)  340 A of the perimeter sash assembly  340  via an attachment assembly  20 . At least one first intermediate glazing layer  330 A is attached to the first surfaces  440 A of the spacer assembly  440 , and at least one second intermediate glazing layer  330 B is attached to the second surfaces  440 B of the spacer assembly  440 . It should be noted that additional spacer assemblies  440  and additional intermediate glazing layers  330  can be included in accordance with the various embodiments of the present invention, as provided above with reference to  FIG.  11   , for example. Finally, an outer glazing layer  230  is attached to the second or outer surfaces  340 B of the perimeter sash assembly  340 . 
     It should be noted that the various glazing layers  130 ,  230 ,  330  of the present invention is attached to the corresponding surfaces of the sash assembly  340  and/or spacer assembly  440  via an attachment assembly  20 , which, as described above in accordance with other embodiments, may include, but is not limited to, a double-sided adhesive tape. 
     Furthermore, in at least one embodiment, the window assembly may include one or more layers of sealing tape, generally referenced as  350 , adhered or secured to a perimeter of the inner glazing layer  130 , a perimeter of the outer glazing layer  230 , and an exposed portion of the perimeter sash assembly  340  that spans between the inner glazing layer  130  and outer glazing layer  230 , for example, over a top exposed surface of the top perimeter sash  344 , a bottom exposed surface of the bottom perimeter sash  342 , and side exposed surfaces of the side sashes  346 ,  348 . In this manner, the sealing tape  350  secures the joints between glazing layers  130 ,  230  and the corresponding or adjacent portions of the perimeter sash assembly  340 . This can allow for easy repair of the glazing layers  130 ,  230  and can provide waterproof protection to the window assembly. Particularly, in the event one of the glazing layers  130 ,  230  becomes damaged or broken, the sealing tape  350  can be removed or partially removed to easily replace the broken or damaged glazing layer  130 ,  230 . 
     With particular reference to  FIG.  16 C , the window assembly  10  of at least one embodiment can be installed within a window opening  352  of a building in a manner to allow the window assembly  10  to be easily removed, for example, in the event an occupant is in need of an emergency exit or egress from the building. 
     More specifically, at least two stops or framing sections, such as a first (or interior) stop  360  and a second (or exterior) stop  365  are fixed to the building at or near the window opening  352  in a manner to create or define a channel or space  368  therebetween within which a portion of the window assembly  10  is disposed. The stops  360 ,  365  may be constructed of wood, metal, PVC, etc. and may, but need not necessarily, span the entire width of the window opening or a substantial portion of the window opening. For example, in at least one embodiment, stop or framing section  365  is a horizontally elongated structure that may extend from or near one side of the window opening to or near the other side. Similarly, stop or framing section  360  is a horizontally elongated structure that may extend from or near one side of the window opening to or near the other side.  FIG.  16 C  is a sectional and exploded view showing a cross section of two stops  360 ,  365 . 
     In the example illustrated in  FIG.  16 C , the first stop  360  is secured or fixed to an upper surface of the window opening  352 , while the second stop  365  is spaced from the first stop  365  a sufficient distance such that the top portion of the window assembly  10 , such as the top perimeter sash  344 , is able to slide therein and be disposed between the first and second stops  360 ,  365 . In the illustrated embodiment, the second stop  365  is secured to an outside surface of the building and at least partially overhangs the window opening  352  such that a portion of the second stop  365  is aligned with the first stop  360  to define the channel or opening therebetween. Other positions of the first and second stops  360 ,  365  are contemplated within the full spirit and scope of the present invention. 
     Moreover, a bottom exterior stop or framing section  367  may also be provided and fixed to the exterior of the building, as shown in  FIG.  16 C . In some cases, an additional support structure or sill trim frame  366  may be secured to the outside of the window assembly  10 , e.g., secured to the tape  350  or other like portion, in order to allow for attachment with the bottom exterior framing section  367 . It should be noted again that  FIG.  16 C  shows a partially exploded view such that adjacent pieces, for example, trim frame  366  is attached to the adjacent tape  350 , which is attached to the glazing layers  130 ,  230 , which is attached to the sash assembly  340 . 
     Still referring to  FIG.  16 C , vertical side frames  367 A,  367 B extend or are disposed vertically along the left and right sides of the window opening  352 . In this manner, stops or framing sections  365 ,  366 ,  367 ,  367 A, and  367 B frame the window opening vertically on the left and right sides (via  367 A, B) and horizontally on the top and bottom (via stops or frames  365 ,  366 ,  367 ). In some embodiments, vertical framing members  367 A and  367 B, may extend into or over the window opening such that the framing members  367 A and  367 B may act as side stops thereby engaging a portion of the perimeter of the window assembly. Accordingly, reference numerals  376 A and  376 B represent compression gaskets or compression weather stripping disposed between the corresponding vertical stops  367 A,  367 B and an outer or perimeter vertical edge of the window assembly. 
     In other words, vertical stop  367 A may be secured to the building on one side of the window opening, partially extending over and into the window opening, and secured or attached against the window assembly with compression weather stripping  376 A disposed therebetween. Similarly, vertical stop  367 B may be secured to the building on the other side of the window opening, particularly extending over and into the window opening, and secured or attached against the window assembly with compression weather stripping  376 B.  FIG.  16 E  illustrates an external view of the stops  365 ,  367 A,  367 B and  366  overlapping the window opening  352 , as described herein. Similar to other figures herein,  FIG.  16 E  is partially exploded in that stop  367 A of at least one embodiment may abut or connect to stop  365  and  366 , and stop  367  may abut or connect to stop  365  and  366 . Similarly, as shown in  FIG.  16 C , stop  366  may abut or connect to  377  with a compression weather stripping  376  there between. 
     Furthermore, a locking assembly  370  may also be included and disposable between a locked orientation (thereby locking the window assembly  10  in place) and an unlocked orientation (thereby allowing the window assembly  10  to be installed or easily removed, for example, in the event of an emergency exit or egress.) More specifically, the locking assembly  370  is disposed between the window assembly and the window opening  352  or between the window assembly  10  and a fixed portion of the building such as a framing fixture, wall, base, etc. 
     As just an example, the one or more locking assemblies  370  of at least one embodiment may include a sliding rail lock or pin  372  that is disposable into a corresponding and aligned locking hole located in a fixed position, for example, on the building or framing fixture(s) of the window opening. Sliding the lock or pin within the corresponding locking hole will cause the window assembly  10  to be secured in place, as shown in  FIG.  16 C , for example. Removing the lock or pin from the corresponding locking hole will disengage or unlock the locking assembly  370 , allowing the window unit  10  to be pushed out of the window opening (e.g., to the right in  FIG.  16 C ) or pulled into the building through the window opening (e.g., to the left in FIG.  16 C). Other locking assemblies structured to facilitate practice of the present invention in the intended manner are contemplated herein. 
     In some embodiments, one or more handles or finger-pull hardware may be installed on the inside of the window assembly to assist the user in pulling the window assembly away from and completely out of the window opening. This will, thus, create an opening through which an occupant can easily escape or egress, for example, in the event of a fire or other emergency situation. 
     In certain embodiments, the window assembly  10  may fit between twenty four inches on center framing or within an opening that leaves twenty two inches minimum of a clear opening for egress, or otherwise an opening that meets emergency egress requirements of building codes. This window assembly  10  can also be installed within the window opening without the use of structural headers, jack and cripple studs that are associated with the installation of conventional windows. 
     It should also be noted that, as shown by reference character  376  in  FIG.  16 C , for example, compression weather stripping can be disposed between various the one or more stops  360 ,  365 ,  367  and corresponding portions of the window assembly  10 , for example, a portion of the glazing layers  130 ,  230  thereof, in order to facilitate or create a tight and in some cases waterproof seal therebetween. The locking assembly  370 , when locked, can serve to secure the window assembly  10  against the one or more compression weather stripping or gaskets  376 . 
     Referring now to  FIG.  16 D , the window assembly  10  of at least one embodiment may be constructed with a window height H and window sash width W or depth that strategically provides passive seasonal shading. For example, the summer sun (generally referenced as S1 in  FIG.  16 D ) is higher in the sky (on south facing elevations, for example) than the winter sun (generally referenced as S2). The window assembly  10  can be constructed or dimensioned such that the summer sun rays are shaded or substantially shaded by the sash assembly  340  (as schematically illustrated) such that the summer sun rays do not enter the building interior or are at least partially, and in some cases, substantially blocked, by the sash assembly  340 . In particular, the window assembly  10  may be dimensions such that the summer sun rays may be at least partially blocked by the outer edge of the top sash, such that the rays will fall within the width or depth W of the sash assembly  340  and are thus substantially or at least partially blocked from entering the building interior. This, of course, avoids or reduces solar heat gain on the interior of the building. In this manner, the window height H may be approximately twice or double the size of the sash width/depth W. As just an example, the window height or sash height H may be about five and a half inches, whereas the sash width/depth W may be about two and a half inches—approximately a 2:1 ratio. Of course, other dimensions and ratios are contemplated. 
     Conversely, since the winter sun (S2) is lower in the sky than the summer sun (S1), the winter sun rays may pass through the window assembly  10  to provide solar heat gain to the interior of the building. 
     With reference now to  FIG.  17   , a front view of a window assembly of at least one embodiment is shown with the use of a diffusion grid  480  disposed on a portion thereof. Fixed louvers or supports  482  may be dispose within one or more of the insulating air spaces disposed or defined between adjacent glazing layers  130 ,  230 ,  330 . The fixed louvers or supports  482  may be adhered or fixed or one or more surfaces of the adjacent glazing layers and can be used to hold or support the diffusion grid  480 . The diffusion grid can be used to provide summer shading, winter gain, and year round daylight bounced deeper into the interior space of the building by diffusing the sun light disposed there through. In some cases, the diffusion grid can be used as providing glare control, as well. In other embodiments, tinting or other light deflection or reduction structures can be used on the surface of one or more of the glazing layers or between adjacent glazing layers. It should be noted that the window assembly shown in  FIG.  17    can be a retrofit assembly attachable to an existing window unit, for example, via one or more spacer assemblies, as disclosed herein. In other embodiments, the window assembly may be un the form of a stand-alone window unit for new construction or replacement windows. 
       FIG.  18    is an exemplary top-down sectional view of a retrofit window assembly, similar to that shown in  FIG.  8    and described above. In particular, an existing window unit may include one or more windows  5  secured to (typically metal or aluminum) frame  2 . This is a common storefront window construction, although not necessarily limited to such. In particular, a first spacer  40 A is secured to one of the exposed existing window units  5  with a glazing layer  30  secured to the opposite side of the spacer  40 A to create an insulating airspace  14  therebetween. The installation may continue with successive, one-by-one installation of spacers  40 A,  40 B,  40 C,  40 D and glazing layers  30  until the desired amount of insulating airspaces  14  or glazing layers  30  is achieved. It should also be noted that spacers  40 A,  40 B,  40 C and  40 D can insulate the existing metal sash  2 . 
     More in particular, the installation process begins with the attachment of the first spacer  40 A to the window unit  5 . Then, the first glazing layer  30  is attached to the first spacer  40 A, as shown in the example of  FIG.  18   . Next, a second spacer  40 B is attached to the exposed surface of the first glazing layer  30 , and a second glazing layer  30  is attached to the second spacer  40 B. This process continues with alternating installation of spacers  40  and glazing layers. As described above in connection with at least one embodiment, the spacers and glazing layers may be attached via one or more strips of double-sided adhesive tape. Optionally, an interior trim  402  can be installed around the perimeter of the last glazing layer  30  for ornamentation. 
     With reference now to  FIG.  19   , a further embodiment of the present invention may include a window assembly, or as shown, a skylight assembly  500  with one or more integrated light assemblies or light structures  510 . Specifically, window or skylight assembly  500  may include one or more light emitting diode (LED) structures or arrays  510  structured to emit light into the building interior. For example, the LED structures  510  may be secured to one or more of the glazing layers  30  and/or any framing or enclosure sections, such as the sash assembly  340 , spacer assembly  440  or portions of the skylight structural enclosure elements  520 . In some cases, the LED structures may be secured around the perimeter or near the outer edges of one or more of the glazing layers  30  and/or inside the perimeter of the skylight enclosure  520 . 
     Furthermore, and still referring to  FIG.  19   , one or more solar or photovoltaic panels  515  can be mounted to the exterior of the skylight enclosure  520  and/or portions of the window or skylight assembly  500 . The solar or photovoltaic panel(s)  515  can be used to charge or supply power to one or more batteries generally referenced as  518 , with a voltage regulation circuit as needed. The one or more batteries  18  are used to supply power to the one or more LED structures  510 . In some embodiments, one or more photocell (or other) light sensors  519  may be included to control the LED structures. In other words, depending on the results of the sensors and the particular sunlight at the time, the light sensor(s)  519  and/or another control assembly can automatically control the light output, by either turning the LEDs on or off, dimming or brightening the LEDs, changing the LED color or hue output, etc. In one example, the skylight assembly  500  can be used to autonomously (vie the sensor(s), LED structure(s) and/or control assembly) provide daylight by day (e.g., by turning off the LED structures during the day) and electric light by night (e.g., by tuning on the LED structures). 
     With reference now to  FIGS.  20 A- 20 C , yet another embodiment of the multi-glazed window assembly  600  of the present invention is shown. In particular, as shown in  FIG.  20 A , the multi-glazed window assembly  600  includes one unit  602 , which has at least two spaced apart glazing layers  604   a ,  604   b , and at least one spacer assembly  610  disposed between the glazing layers  604   a ,  604   b  while collectively defining an insulating airspace, referenced as  605 . In some embodiments, one or all of the insulating airspaces  605  may include a width (e.g., measured between the inside surfaces of adjacent glazing layers  604   a ,  694   b ) of approximately ¾ inches, although other sizes are contemplated within the full spirit and scope of the present invention. Furthermore, each glazing layer  604   a ,  604   b  may be 0.08 inch acrylic panels, although other sizes and other materials are contemplated and included within the present invention. 
       FIG.  20 B  illustrates a multi-glazed window assembly  600  with a plurality of (e.g., two) adjacent or side-by-side units  602 . In this embodiment, the two units  602  may share a common, intermediately disposed glazing layer, which is shown as glazing layer  604   b . More specifically, three glazing layers  604   a - c  are spaced from one another in a generally parallel (but not necessarily) manner to form two insulating airspaces  605 ; one or a first insulating airspace  605  disposed or defined between glazing layers  604   a  and  604   b , and another or a second insulating airspace  605  disposed or defined between glazing layers  604   b  and  604   c.    
       FIG.  20 C  is provided to illustrate that several more units  602  can be assembled together in the same or similar manner as that shown in  FIG.  20 B  to define a multi-glazed window assembly  600  that defines two or more insulating airspaces  605 . In particular, the multi-glazed window assembly  600  of the present invention may define one through nine, or more, insulating airspaces  605 . Each insulating airspace  605  may include a spacer assembly  610  disposed between adjacent glazing layers  604   a - n  as provided herein. As shown, glazing layers  604   a - n  can be used to define the insulating airspaces  605 . Adjacent units  602  can share a common glazing layer (e.g., as provided in  FIG.  20 B ), although it is contemplated that in some cases each unit  602  may include distinct pairs of glazing layers such that adjacent units may not share a common glazing layer, but may instead have abutting, adjacent glazing layers. 
     It should also be noted that, in at least one embodiment of the present invention constructed in accordance with the embodiments illustrated in  FIGS.  20 A-C  may exhibit an R-value of approximately 4.5 with three insulating airspaces (three spacer assemblies  610  and four glazing layers), an R-value of approximately 6.8 with five insulating airspaces (five spacer assemblies  610  and six glazing layers), and an R-value of approximately 9.4 with seven insulating airspaces (seven spacer assemblies  610  and eight glazing layers). 
     In any event, the spacer assembly  610  of at least one embodiment includes a clear (e.g., transparent) or partially clear (e.g., translucent) tube  612 . The tube  612  may, in some embodiments, include a square or rectangular cross-section with sharp or rounded corners, however, other shapes, including other polygonal shapes, circular or oval shapes, etc. are contemplated. Furthermore, the tube  612  or spacer assembly  610  of at least one embodiment may be constructed out of acrylic or other like materials. As just an example, the tube  612  may be a 3  inch thick acrylic square tube, although other materials, shapes and sizes are contemplated within the full spirit and scope of the present invention. 
     In addition, the tube  612  or spacer assembly  610  of at least one embodiment may function as the sash or frame of the window assembly. In other words, the assembly  600  of at least one embodiment may eliminate the need for or otherwise replace the sash and frame typically found on many traditional or common window units. 
     In some embodiments, the tube  612  of the spacer assembly  610  defines opposing lateral sides, referenced as  614   a ,  614   b  which are attached to the respective glazing layer  604   a ,  604   b . In some cases, as described in accordance with other embodiments presented herein, the spacer assembly  600  or tube  612  thereof may be attached to the glazing layers  604   a ,  604   b  via peel-and-stick, double-sided adhesive tape, referenced as  606   a ,  606   b , although other manners of adhering, connecting or attaching the tube(s)  612  to the corresponding glazing layer(s), e.g.,  604   a ,  604   b ,  604   n , is contemplated. It should be noted that in the illustrations provided at least in  FIGS.  20 A   20 C, the double-sided adhesive tape  606   a ,  606   b  is shown separated from the surfaces of the corresponding glazing layer  604   a ,  604   b  and the tube  612 , however, that is for illustrative purposes only and it should be apparent that, in operation, the tape  606   a - b  adhesively contacts the facing surfaces of the glazing layer and tube. The thickness and size of the tape  606   a - b  shown in the drawings is also provided for illustrative purposes and may not be to scale. 
     Furthermore, still referring to  FIGS.  20 A-C , in at least one embodiment, a sealant  620  may be placed along a longitudinal edge  614   c  of the tube  612 , such as, between a perimeter edge  607  and the tube  612 . In some cases, the sealant  620  may span the entire longitudinal edge or surface  614  while also extending at least partially along the opposing lateral edges or surfaces  614   a ,  614   b  of the tube  612  and between the tube  612  and the corresponding glazing layer(s)  604   a ,  604   b . This sealant  620  can assist with the secure attachment of the spacer assembly  610  to the perimeter edge  607  and the glazing layers  60   a ,  604   b . It should also be noted that the sealant  620  may be thinner than shown in the Figures in that the sealant  620  shown is for illustrative purposes and may not be to scale. For example, in one embodiment, the spacer assembly  610  and in particular the tube  612  thereof may be disposed at or approximately at ⅛ inches in from the glazing layer(s)  604   a ,  604   b , and in some cases, ⅛ inches up (or in) from the perimeter edge  607 . It should also be noted that the distance (e.g., ⅛ inches) between the tube  612  and the glazing layer  604   a ,  604   b  may be measured from the inside surface of the glazing layer, the outside surface of the glazing layer, or the center of the glazing layer. 
     It should also be noted that in some embodiments, double-sided adhesive tape can also be used between the tube  612  and the perimeter edge  607  in addition to or instead of the sealant  620 . 
     Furthermore, in at least one embodiment, the tube  612  of the spacer assembly  610  may define an open interior space, generally referenced as  615 . In other words, the clear acrylic (or other) tube  612  of the spacer assembly  610  may include an interior area that is generally open or available to be filled with another material. With reference now to  FIG.  21   , the cross-hatched shading provided on the interior of at least one of the tubes  612  represents a filling material  630  disposed therein. This filling material  630  may be present in one of the tube(s)  612 , all of the tube(s)  612  or in any number of less than or equal to all of the tube(s)  612 . 
     More in particular, the filling material  630  shown in  FIG.  21    may include a phase-change material or medium that can provide integral heat or thermal storage designed to reduce the overall energy costs associated with heating or cooling the corresponding building or room within which the window assembly  600  is installed. As an example, the filling material  630 , such as the phase-change material, may melt between 67 degrees and 74 degrees Fahrenheit with heat enthalpy of 60,000 BTU/cf.×0.048 cf in a  2278  window with one perimeter loop of PCM, which is 2880 BTU of latent heat storage/loop. Of course, this is merely exemplary and other materials with other heat storage and the like properties are contemplated as filling materials  630 . 
     Furthermore, with reference to  FIGS.  22 A and  22 B , in at least one embodiment of the present invention, one or more light assemblies or light sources  640  may be disposed within one or more of the insulating airspaces  605 , and in some cases, within the one or more spacers or tubes  612 . Moreover, the at least one light assembly or light source  640  may be in the form of or otherwise include a light emitting diode (LED) however other light sources are contemplated within the scope of the present invention including compact fluorescent lamps (CFLs), halogen lights, light strips, etc. 
     In any event, as shown in  FIGS.  22 A- 22 B , the light source  640  may be electrically attached to a power source  642 , such as one or more batteries, although other power sources are contemplated. In particular, the one or more batteries may be replaceable or rechargeable. In some cases, the one or more batteries  642  may be rechargeable wirelessly through the glazing layer(s) such that physical access thereto may not be needed. In other embodiments, a cable (not shown) may be passed from the light source  640  to a location external to the assembly  600  (e.g., through a corresponding hole or channel), which can then be plugged in or electrically connected to a power source. 
     The light source  640 , when illuminated, can provide edge-to-edge lighting to the window assembly  600 , for example, by lighting the edges of, between the edges of, and/or to the edges of the glazing layer(s)  604   a - n  and/or the clear tube(s)  612 . This is particularly true with acrylic glazing layers although glass and other materials can also produce edge lighting. 
     Furthermore, in at least one embodiment, a light-transmitting thermal storage medium may be disposed between at least two of the glazing layer(s)  604   a - n  and/or within the one or more spacers or clear tubes  612 . For instance, an example of a light-transmitting thermal storage medium may be water, although other mediums, whether liquid, solid or otherwise, are contemplated. 
     It should also be noted that, as described in accordance with other embodiments provided herein, the glazing layers  604   a - n  of at least one embodiment transfer structural roof loads of the building within which the assembly  600  is installed. In some cases, the window assembly  600  can be installed without a window header. Furthermore, multiple glazing layers  604   a - n  can act as structural diaphragms of a stress-skin panel, as disclosed in accordance with other embodiments provided herein. 
     Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the example chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention. This written description provides an illustrative explanation and/or account of the present invention. It may be possible to deliver equivalent benefits using variations of the specific embodiments, without departing from the inventive concept. This description and these drawings, therefore, are to be regarded as illustrative and not restrictive. 
     Now that the invention has been described,