WO2017056108A1

WO2017056108A1 - System and method for retro-fitting glazing unit

Info

Publication number: WO2017056108A1
Application number: PCT/IN2016/050325
Authority: WO
Inventors: Vinay NATRAJAN; John PATTERY
Original assignee: Saint-Gobain Glass France
Priority date: 2015-09-28
Filing date: 2016-09-27
Publication date: 2017-04-06
Also published as: PH12018500498A1

Abstract

A method of converting an installed glazing unit to a multiple glazing unit at an installation site is provided. The method includes, providing, at the installation site, a secondary glazing unit and a spacer element. The method further includes co-axially aligning the secondary glazing unit with the installed glazing unit using first and second fixture elements that couple with each other. The method also includes filling a sealant optionally using a sealant applicator tool in a clearance between the installed glazing unit and the secondary glazing unit to bond the secondary glazing unit and the existing glazing unit to each other. A system for improving energy efficiency and thermal comfort of a building using the method of the present invention is also disclosed.

Description

SYSTEM AND METHOD FOR RETRO-FITTING GLAZING UNIT

Technical Field

[0001] The present disclosure relates in general to glazings of a building and, in particular, to a system and method for retro-fitting glazing units.

Background

[0002] In many buildings, single glazings have been installed. However, such single glazings may not provide effective cooling or heating thereby increasing costs for cooling and/or heating devices within the building. Moreover, after the lifetime of a sealant used for sealing the glazings in the window frames, the sealant may start deteriorating which can result in damage of the glazing unit. However, replacing the existing glazing with double or triple glazings may incur high labor and material costs.

[0003] Methods for adding an additional glazing to an existing glazing are available. These methods include adding the glazing from outside that requires setting up complex scaffoldings. Other methods include adding the glazing directly to the frame. Such methods may not provide an effective shield against moisture which can still leak in thereby increasing the chances of condensation. In other cases, specially designed glazings, spacers or other components may be used for converting the existing glazings to multiple glazings. However, use of these new components may incur production and/or manufacturing costs.

[0004] For reference, Japanese patent publication 2015/036354 discloses a method for attaching a glass plate with a spacer on a glass window and providing a hollow layer between the glass window and the glass plate to which the spacer is attached. The heat insulation gas is injected into the hollow layer using nozzle to improve the thermal insulation performance. This method depends on using a specially designed spacer and also focuses on converting a single glazing to a double glazing unit. However, use of these specially designed components may not be suitable for customization and may incur production and/or manufacturing complexities along with additional costs. [0005] Hence, there exists a need for an improved and simple method and/or system for adding one or more glazing units to an existing glazing from inside of the building.

Summary of the Disclosure

[0006] In one aspect of the present disclosure, a method of converting an installed glazing unit to a multiple glazing unit at an installation site is provided. The method includes, providing, at the installation site, a secondary glazing unit and a spacer element. The spacer element has a first surface and a second surface opposite to the first surface. The first surface is attached to the secondary glazing unit. The method also includes attaching the second surface of the spacer element to an inner side of the installed glazing unit. The method further includes filling a sealant in a clearance between the installed glazing unit and the secondary glazing unit to bond the secondary glazing unit and the existing glazing unit to each other.

[0007] In another aspect of the present disclosure, an installation system for converting an installed glazing unit to a multiple glazing unit at an installation site is provided. The installation system includes a secondary glazing unit and a spacer element. The spacer element has a first surface and a second surface that is opposite to the first surface. The first surface is configured to be attached to the secondary glazing unit. The second surface is configured to be attached to an inner side of the installed glazing unit. The installation system also includes a sealant and a sealant applicator configured to allow the flow of a sealant to a clearance between the installed glazing unit and the secondary glazing unit. The sealant applicator includes a thicker end defining a central hole that is configured to receive the sealant therethrough. The sealant applicator also includes a thinner end configured to be removably inserted in the clearance. The thinner end defines an elongated channel that is in fluid communication with the central hole. The thinner end is further configured to fill the clearance with the sealant received via the central hole and the elongated channel.

[0008] In yet another aspect of the present disclosure, a sealant applicator for filling a sealant in a clearance between two glazing units that are attached to each other is provided. At least one of the two glazing units is installed in a frame. The sealant applicator includes a thicker end that defines a central hole for receiving the sealant therethrough. The sealant applicator also includes a thinner end configured to be removably inserted in the clearance. The thinner end defines an elongated channel in fluid communication with the central hole and configured to fill the clearance with the sealant received from the central hole.

[0009] In yet another aspect of the present disclosure, a fixture system for adding a secondary glazing unit to an inner side of an installed glazing unit that is attached to a window frame is provided. The fixture system includes a first fixture element configured to be disposed on at least one corner of the inner side of the installed glazing unit. The first fixture element defines a first aperture therethrough. The fixture system also includes a second fixture element configured to be disposed at a corresponding corner of the second glazing unit. The second fixture element defines a second aperture therethrough. The first and second fixture elements are configured to align the secondary glazing unit generally parallel to the installed glazing unit by co-axially aligning the second aperture with the first aperture.

[0010] In yet another aspect of the present disclosure, a multiple glazing unit is provided. The multiple glazing unit includes a window frame attached to a wall structure and an installed glazing unit having an inner side and attached to the window frame. The multiple glazing unit also includes a secondary glazing unit added to the inner side of the installed glazing unit in a substantially parallel and spaced apart relation from the installed glazing unit. The multiple glazing unit further includes a spacer element that is disposed between the installed glazing unit and the secondary glazing unit. The multiple glazing unit includes a weather resistant sealant disposed in a clearance between the installed glazing unit and the secondary glazing unit. The multiple glazing unit also includes a first fixture element disposed on at least one corner of the inner side of the installed glazing unit. The multiple glazing unit further includes a second fixture element disposed on a corresponding corner of the secondary glazing unit. The second fixture element and the first fixture element are coupled to each other. [0011] In yet another aspect of the present disclosure, a system for improving energy efficiency and thermal comfort of a building using the method of the present invention is also disclosed.

[0012] Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

Brief Description of the Drawings

[0013] Embodiments are illustrated by way of example and are not limited in the accompanying figures.

[0014] FIG. 1 illustrates a partial perspective view of an exemplary installed glazing unit attached to a window frame;

[0015] FIG. 2 illustrates an exploded view of an installation system for converting the installed glazing unit to a multiple glazing unit, according to an embodiment of the present disclosure;

[0016] FIG. 3 illustrates an partially exploded view of the multiple glazing unit, according to an embodiment of the present disclosure;

[0017] FIG. 4 illustrates a perspective view of a first fixture element of the installation system, according to an embodiment of the present disclosure;

[0018] FIG. 5 illustrates a perspective view of a second fixture element of the installation system, according to an embodiment of the present disclosure;

[0019] FIG. 6 illustrates a perspective view of a sealant applicator configured to fill the sealant in a clearance between the installed and secondary glazing unit, according to an embodiment of the present disclosure;

[0020] FIG. 7 illustrates a rear perspective view of the multiple glazing unit showing a sealant applicator being used to fill a clearance with a sealant, according to an embodiment of the present disclosure;

[0021] FIG. 8 illustrates a front perspective view of the multiple glazing unit showing a sealant applicator being used to fill a clearance with a sealant, according to an embodiment of the present disclosure;

[0022] FIG. 9 illustrates a cut away view of the multiple glazing unit showing the sealant filled in the clearance, according to another embodiment of the present disclosure; and [0023] FIG. 10 illustrates a flowchart for a method of converting an installed glazing unit to a multiple glazing unit, according to an embodiment of the present disclosure.

[0024] FIG. 11 illustrates graphs plotted on solar radiation, inside and outside temperature, inside surface temperature and heat-ingress for glazing units for SGU and TGU.

[0025] FIG. 12 shows the operative temperatures (T_OP) recorded in rooms fitted with glazing units.

[0026] Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention.

Detailed Description

[0027] Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts. FIG. 1 illustrates an exemplary wall structure 100. The wall structure 100 may include window frame 102. Further, as shown, the wall structure 100 may include an exemplary installed glazing unit 104 attached to the window frame 102. In the illustrated example, the installed glazing unit 104 may include a single glazing. The installed glazing unit may have a rectangular shape defining four corners 106. In another example, the installed glazing unit 104 may be a double glazing unit (DGU). In various other examples, the installed glazing unit 104 may include any number of glazings. Further, the installed glazing unit 104 may have an inner side 108 towards an interior of the wall structure 100.

[0028] Referring to FIGS. 2 and 3, an installation system 200 is configured to convert the installed glazing unit 104 to a multiple glazing unit 201 (shown in FIG. 9) at an installation site 202, according to an embodiment of the present disclosure. The installation site 202 may refer to a site at which the window frame 102 and the corresponding installed glazing unit 104 are located. In an example, the installation site 202 may be a building comprising the wall structure 100 with the installed glazing unit 104.

[0029] The installation system 200 includes a secondary glazing unit 204 configured to be added to the installed glazing unit 104. In the illustrated embodiment, the secondary glazing unit 204 may be a double glazing unit (DGU). In another embodiment, the secondary glazing unit 204 may include a single glazing. In various other embodiments, the secondary glazing unit 204 may include any number of glazings. The secondary glazing unit 204 and the installed glazing unit 104 are together configured to form the multiple glazing unit 201. The secondary glazing unit 204 may have a rectangular shape defining four corners 205. The secondary glazing unit 204 may have a size that is less than the size of the window frame 102. As shown, a periphery 206 of the secondary glazing unit 204 may have a first offset Dl with respect to the window frame 102. In an example, the first offset Dl may be equal to 10 mm. Further, the secondary glazing unit may have a total thickness Tl. In an example, the thickness Tl may be equal to 24 mm.

[0030] The installation system 200 also includes a spacer element 207. In the illustrated embodiment, the spacer element 207 may also have a rectangular shape. The spacer element 207 may have a thickness T2. In one embodiment, the thickness T2 of the spacer element 207 may be greater than or equal to 20 mm. In another embodiment, the thickness T2 of the spacer element 207 may be approximately equal to 10 mm. In various other embodiments, the thickness T2 of the spacer element 207 may be chosen based on the type of application.

[0031] In an example, the spacer element 207 may be made of aluminum. In various other examples, the spacer element 207 may be made of poly carbonate based composites, metals and the like. In an embodiment, the spacer element 207 may be formed by bending an elongated strip of the suitable material to a required shape. Suitable bending tools may be employed to bend the elongated strip to form the spacer element 207. In other embodiments, multiple strips may be suitably joined to form the spacer element 207.

[0032] The spacer element 207 has a first surface 208 and a second surface 210 that is opposite to the first surface 208. The spacer element 207 also includes an inner surface 212 and an outer surface 214. The first surface 208 is configured to be attached to a side of the secondary glazing unit 204. The second surface 210 is configured to be attached to the inner side 108 of the installed glazing unit 104. The spacer element 207 may have a size that is less than the size of the secondary glazing unit 204. Further, the outer surface 214 of the spacer element 207 may have a second offset D2 with respect to the periphery 206 of the secondary glazing unit 204. In an example, the second offset D2 may be approximately equal to 8mm.

[0033] In one embodiment, the spacer element 207 may be attached to the installed glazing unit 104 and/or the secondary glazing unit 204 using an adhesive based foam material. The adhesive based foam material may be a tape, e.g., a 3 mm two sided tape. In such a case, the tape may be attached to each of the first surface 208 and the second surface 210 by removing a liner of the tape. Further, a liner on other side of each of the tapes may be removed for attaching the spacer element 207 to the respective installed glazing unit 104 and the secondary glazing unit 204.

[0034] In other embodiments, the spacer element 207 may be attached to the installed glazing unit 104 and/or the secondary glazing unit 204 using other suitable adhesives such as, an acrylic foam adhesive, a butyl coated poly-vinyl chloride, a poly-isobutyl adhesive and the like. However, it may be contemplated to use other types of adhesives, suitable mechanical fasteners and the like to accomplish the attachment between the spacer element 207 and each of the installed glazing unit 104 and the secondary glazing unit 204.

[0035] In an embodiment, the installation system 200 may include a fixture system 400 configured to align the secondary glazing unit 204 generally parallel to the installed glazing unit 104. Referring to FIGS. 3 to 5, the fixture system 400 is configured to be disposed on the respective installed glazing unit 104 and the secondary glazing unit 204. The fixture system 400 includes a first fixture element 402 and a second fixture element 404. The first fixture element 402 is configured to be disposed on at least one of the corners 106 of the inner side 108 of the installed glazing unit 104. In the illustrated embodiment, the fixture system 400 includes four first fixture elements 402 disposed on the inner side 108 and adjacent to each of the corners 106 of the installed glazing unit 104.

[0036] The second fixture element 404 is configured to be disposed on the corresponding corners 205 of secondary glazing unit 204. In the illustrated embodiment, the fixture system 400 includes four second fixture elements 404 disposed on each of the corners 205 of the secondary glazing unit 204. Further, the second fixture elements 404 are disposed on the periphery 206 adjacent to the corners 205 of the secondary glazing unit 204.

[0037] In an embodiment, the first and second fixture elements 404 may be attached to the respective installed glazing unit 104 and the secondary glazing unit 204 using suitable adhesives. In an example, the adhesive may be a silicone based adhesive. In other examples, any other suitable adhesives may be used to attach the first and second fixture elements 404 to the respective installed glazing unit 104 and the secondary glazing unit 204.

[0038] Moreover, each of the first fixture elements 402 and the second fixture elements 404 may be disposed on the respective installed glazing unit 104 and the secondary glazing unit 204 before attaching the spacer element 207 to the installed glazing unit 104. As such, by aligning each of the second fixture elements 404 with the corresponding first fixture elements 402, the secondary glazing unit 204 may be aligned generally parallel to the installed glazing unit 104.

[0039] Referring to FIG. 4, the first fixture element 402, according to an embodiment of the present disclosure is illustrated. Referring to FIG. 5, the second fixture element 404, according to one embodiment of the present disclosure is illustrated. The second fixture element 404 of FIG. 5 may be used for the secondary glazing unit 204 having at least two glazings. In the illustrated embodiment, each of the first fixture element 402 and the second fixture element 404 may have an L-shape. Further, each of the first fixture element 402 and the second fixture element 404 may have a width approximately equal to the first offset Dl. As such, the secondary glazing unit 204 along with the second fixture elements 404 may be disposed within the window frame 102. [0040] The first fixture element 402 may define a first aperture 406 therethrough and the second fixture element 404 may define a second aperture 408 therethrough. The first aperture 406 and the second aperture 408 are configured to co-axially align with each other so as to align the secondary glazing unit 204 generally parallel to the installed glazing unit 104.

[0041] Referring to FIG. 5, the second fixture element 404 may define one or more extensions 410 that may be configured to be inserted in between the two glazings of the secondary glazing unit 204. Further, a secondary sealant may be disposed between the two glazings. In an example, the second fixture element 404 may be installed on the secondary glazing unit during manufacturing of the secondary glazing unit. In an embodiment, where the second glazing unit has a single glazing, the second fixture element 404 may also have a configuration similar to the configuration of the first fixture element 402 of FIG. 4.

[0042] Further, the first fixture element 402 and the corresponding second fixture element 404 may be coupled to each other. In an example, suitable mechanical fasteners such as, but not limited to, studs, bolts, screws and the like may be used to accomplish the coupling between the first fixture element 402 and the corresponding second fixture element 404. Additionally or optionally, one of the first and second fixture elements 404 may have a projection (not shown), and other of the first and second fixture elements 404 may define a receiving hole. With such a configuration, by receiving the projections in the respective receiving holes, the secondary glazing unit 204 and the installed glazing unit 104 may be suitably aligned.

[0043] Further, each of the first fixture element 402 and the second fixture element 404 may also define holes 412, 414 respectively. The holes 412 of the first fixture element 402 and the corresponding holes 414 of the second fixture element 404 are configured to be in fluid communication with each other upon adding the secondary glazing unit 204 to the installed glazing unit 104.

[0044] Other suitable shapes and configurations of the first fixture element 402 and the second fixture element 404 may also be contemplated for use in aligning the first aperture 406 and the second aperture 408, thereby aligning the secondary glazing unit 204 and the installed glazing unit 104 parallel to each other. For example, the second fixture element 404 may have any shape that conforms to a shape of the corresponding corner 205 of the secondary glazing unit 204. The first fixture element 402 may be accordingly configured with respect to the second fixture element 404.

[0045] Referring to FIGS. 6 to 8, the installed glazing unit 104, the inner surface 212 of the spacer element 207 and the secondary glazing unit 204 defines a cavity 418 therebetween. Moreover a volume of the cavity 418 may depend on the thickness T2 of the spacer element 207.

[0046] In an embodiment, a moisture barrier (not shown) may be disposed at least on the outer surface 214 of the spacer element 207. In an example, the moisture barrier may be an aluminum foil. The moisture barrier may be configured to restrict the moisture from passing therethrough. Moreover, the moisture barrier may also be used to cover any joints on the spacer. As such, the moisture barrier may restrict the moisture from entering through the joints of the spacer element 207.

[0047] In an embodiment, the inner surface 212 of the spacer element 207 may define one or more micro-holes (define) therein. In an embodiment, the spacer element 207 may contain a hygroscopic material therein. In one example, the hygroscopic material may be a desiccant such as a silicon material. The hygroscopic material may be provided to dry up the moisture entering the spacer element 207 through the micro-holes. As such, the cavity 418 between the installed glazing unit 104 and the secondary glazing unit 204 may be rendered moisture free.

[0048] Further, the installed glazing unit 104, the secondary glazing unit 204 and the outer surface 214 of the spacer element 207 also defines a clearance 420 thereabout. Specifically, the clearance 420 may be defined between the outer surface 214 of the spacer element 207, the inner side 108 of the installed glazing unit 104, and the secondary glazing unit 204 that is adjacent to the periphery 206 thereof. Accordingly, the clearance 420 may include four portions disposed between the adjacent corners 205 of the secondary glazing unit 204.

[0049] The clearance 420 is filled with a sealant 424 (see FIG. 9) to bond the installed glazing unit 104 and the secondary glazing unit 204 to each other, as will be explained herein with reference to FIGS. 6 to 9. The installation system 200 further includes the sealant 424 configured to be filled within the clearance 420.

[0050] In an embodiment, the sealant 424 may have a viscosity greater than or equal to 1300 centipoise. Further, the sealant 424 may have a tensile strength greater than or equal to IMPa. In an embodiment, the sealant 424 may be a silicone based adhesive. In an example, the sealant 424 may be a transparent sealant. In other embodiments, other types of suitable sealants 424 may be used to structurally bond the installed and secondary glazing units 104, 204.

[0051] In an embodiment, an amount of the sealant 424 used for attaching the installed and secondary glazing units 104, 204 may be selected based at least on a weight of the installed and secondary glazing units 104, 204 and various properties of the sealant 424 being used. Accordingly, a volume of the clearance 420 defined between the installed and secondary glazing units 104, 204 may be varied. As such, the thickness T2 of the spacer element 207 may be varied based on the volume of the clearance 420 required to fill the required amount of the sealant 424. Similarly, the second offset D2 may be additionally or optionally varied to consequently vary the volume of the clearance 420 required to fill the required amount of the sealant 424.

[0052] Referring to FIGS. 6 to 9, the installation system 200 further includes a sealant applicator 500 that is configured to allow a flow of the sealant 424 to the clearance 420. The sealant applicator 500 includes a thicker end 502 and a thinner end 504 that may extend from the thicker end 502. The thicker end 502 defines a central hole 506 configured to receive the sealant 424 therethrough. In an embodiment, a pressurized filling tool may be used to supply the sealant 424 through the central hole 506. In one example, the pressurized filling tool may be an electrically pressurized filling tool. In another example, the pressurized filling tool may be a pneumatically pressurized filling tool. Various other suitable filling tools may also be contemplated for use in supplying the sealant 424 to the central hole 506.

[0053] The thinner end 504 is configured to be removably inserted in the clearance 420. The thinner end 504 defines an elongated channel 508 that is in fluid communication with the central hole 506. The sealant applicator 500 further includes a draft (not shown) connecting the central hole 506 with the elongated channel 508. An area of the draft at any cross-section may be equal to an area of the central hole 506. As such, a uniform flow velocity may be provided from the central hole 506 and through the draft to the elongated channel 508 thereby preventing any backflow of the sealant 424.

[0054] In an embodiment, the elongated channel 508 may have an oval shape that has a decreased diameter from center towards ends thereof. Other, suitable shapes may also be contemplated for the elongated channel 508.

[0055] The thinner end 504 may have a total length LI and a portion of the thinner end 504 defining the elongated channel 508 may have a length L2. The total length LI may vary based on the thickness T2 of the spacer element 207 and the thickness Tl of the secondary glazing unit 204. In an embodiment, the total length LI of the thinner end 504 may be selected to be substantially equal to a sum of the thickness Tl of the secondary glazing unit 204 and the thickness T2 of the spacer element 207. The total length LI of the thinner end 504 may vary based on the volume of the clearance 420 in which the sealant 424 may need to be filled. In an embodiment, the length L2 may be substantially equal to the thickness T2 of the spacer element 207.

[0056] With such an implementation, the elongated channel 508 is configured to fill the clearance 420 with the sealant 424 received via the central hole 506. The sealant applicator 500 may receive the sealant 424 through the central hole 506 and allow the flow of the sealant 424 through the draft and the elongated channel 508 to the clearance 420. Moreover, the sealant applicator 500 may be moved between the adjacent second fixture elements 404 to fill the corresponding portion of the clearance 420.

[0057] Further, the sealant 424 flowing through the sealant applicator 500 may also flow through the first and second fixture elements 402, 404 via the respective holes 412, 414. Therefore, the sealant applicator 500 may be used to fill the sealant 424 throughout the clearance 420. Moreover, the sealant 424 may also flow to an existing sealant layer that attaches the installed glazing unit 104 to the frame. As such, the strength of the existing sealant layer may be reinforced. [0058] In an embodiment, the installation system 200 may further include a foam spacer (not shown) configured to be disposed in a gap between the window frame 102 and the periphery 206 of the secondary glazing unit 204. Alternatively, at least a portion of the gap may also be filled with suitable sealant or adhesive. In an embodiment, the installation system 200 may further include aesthetically designed clips (not shown) configured to be attached to each of the second fixture elements 404.

[0059] Referring to FIG. 9, the multiple glazing unit 201, according to an embodiment of the present disclosure is illustrated. In an embodiment, the installation system 200 may be used to form the multiple glazing unit 201.

[0060] The multiple glazing unit 201 includes the window frame 102 attached to the wall structure 100. The multiple glazing unit 201 also includes the installed glazing unit 104 having the inner side 108 and attached to the window frame 102. The multiple glazing unit 201 also includes the secondary glazing unit 204 added to the inner side 108 of the installed glazing unit 104 in a substantially parallel and spaced apart relation from the installed glazing unit 104.

[0061] The multiple glazing unit 201 includes the spacer element 207 disposed between the installed glazing unit 104 and the secondary glazing unit 204. Further, the multiple glazing unit 201 includes a weather resistant sealant 424 disposed in the clearance 420 between the installed glazing unit 104 and the secondary glazing unit 204. In one example the weather resistant sealant 424 may be a silicone based adhesive.

[0062] The multiple glazing unit 201 further includes the first fixture element 402 disposed on at least one corner 106 of the inner side 108 of the installed glazing unit 104. The multiple glazing unit 201 also includes the second fixture element 404 disposed on the corresponding corner 205 of the secondary glazing unit 204. Further, the second fixture element 404 and the first fixture element 402 may be coupled to each other.

[0063] The multiple glazing unit 201 thus formed may have a property of resistance to condensation. The multiple glazing unit 201 may also have various properties such as, but not limited to, improved resistance to moisture, insulation to acoustics, higher energy performance and the like. Moreover, the first and second fixture elements 402, 404 enable transfer of at least a part of the load of the secondary glazing unit 204 to the window frame 102 instead of the installed glazing unit 104. As such, the multiple glazing unit 201 has an increased structural strength to the installed glazing unit 104.

[0064] Additionally, the multiple glazing unit 201 includes the sealant 424 filled throughout the clearance 420. As such, the multiple glazing unit 201 may also have various properties such as, but not limited to, insulation to acoustics, increased adhesion strength and the like.

[0065] Referring to FIG. 10, a flowchart for a method 900 of converting an installed glazing unit 104 to a multiple glazing unit 201 at the installation site 202 is illustrated. In an embodiment, the multiple glazing unit 201 of FIG. 9 may be formed by implementing one or more steps of the method 900. The method 900 will be explained in conjunction with one or more components of the installation system 200. However, it may also be contemplated to implement the method 900 with other suitable tools without deviating from the scope of the present disclosure and/or necessary modifications to the described components of the installation system 200.

[0066] At step 902, the method 900 includes providing, at the installation site 202, the secondary glazing unit 204 and the spacer element 207. In one embodiment, the spacer element 207 has a first surface 208 and a second surface 210 opposite to the first surface. In an embodiment, at step 902, the method 900 may also include disposing a moisture barrier around the spacer element 207. In an example, the moisture barrier may be an aluminum foil.

[0067] At step 904, the first surface 208 of the spacer element 207 is attached to the secondary glazing unit 204, at the installation site 202. In another embodiment, the first surface 208 of the spacer element 207 is attached to the secondary glazing unit 204, at other sites such as a factory site and brought to the installation site 202. The spacer element 207 may be attached to the secondary glazing unit 204 using suitable adhesives.

[0068] At step 906, the method 900 includes attaching the second surface 210 of the spacer element 207 to the inner side 108 of the installed glazing unit 104. The installed glazing unit 104 and the secondary glazing unit 204 together define a clearance 420 therebetween upon disposing the spacer element 207 therebetween. Specifically, the clearance 420 may be defined between the spacer element 207 and the surfaces of the installed and secondary glazing units 104, 204 that are adjacent to the peripheries thereof.

[0069] In an embodiment, at step 906, the method 900 may include, disposing the first fixture elements 402 on at least one of the corners 106 of the installed glazing unit 104. Further, the method 900 may also include disposing the second fixture elements 404 on the corresponding corners 205 of the secondary glazing unit 204. Alternatively, in cases where the secondary glazing unit 204 includes more than one glazing, the second fixture elements 404 may be attached during manufacture thereof. Subsequently, the method 900 may include co-axially aligning the second aperture 408 with the first aperture 406 so as to align the secondary glazing unit 204 generally parallel to the installed glazing unit 104. Further, the secondary glazing unit 204 may be biased towards the installed glazing unit 104 and subsequently attached thereto.

[0070] At step 908, the method 900 includes filling the sealant 424 in the clearance 420 to structurally bond the secondary glazing unit 204 and the installed glazing unit 104 to each other. In one example, the sealant 424 may be a silicone based adhesive.

[0071] In an embodiment, at step 908, the method 900 may include disposing the thinner end 504 of the sealant applicator 500 in the clearance 420. The sealant 424 may be supplied through the central hole 506 using a suitable tool. Further, the sealant applicator 500 may be moved throughout the clearance 420 with the sealant 424 being supplied through the central hole 506. As such, the sealant 424 may be filled in all the portions of the clearance 420.

[0072] Although the method 900 and the installation system 200 is explained to be implemented on the inner side 108 of the installed glazing unit 104, it may be contemplated to implement the concepts of the present disclosure from any side of the wall structure 100 and the installed glazing unit 104.

[0073] With an implementation of the method 900, the wall structure 100 may be provided with the secondary glazing unit 204 in addition to the installed glazing unit 104. Therefore, the wall structure 100 provides an improved energy performance compared to the previous setting. Moreover, the secondary glazing unit 204 may be added without removing or altering the existing installed glazing unit 104. Additionally, the method 900 also provides an easy and quick way of filling the sealant 424 in the clearance 420, at the installation site 202. For example, the sealant applicator 500 which may be portable may be used to fill the sealant 424 in the clearance 420. Further, the existing sealant layer between the installed glazing unit 104 and the window frame 102 may be reinforced by filling the sealant 424 in the clearance 420.

[0074] The spacer element 207 may also include an hygroscopic material. The hygroscopic material may be provided to dry up the moisture entering from the cavity 418 to the spacer element 207. The multiple glazing unit 201 formed includes at least three layers of sealant namely, the adhesive used to join the spacer element 207 to the installed and secondary glazing unit 104, 204; the moisture barrier disposed on the spacer element 207; and the sealant 424 disposed between the installed and secondary glazing unit 104, 204 on all sides. With such an implementation, the multiple glazing unit 201 may resist condensation.

[0075] Example 1

[0076] Energy & Thermal Performance Studies

[0077] Two rooms of the same building were used to quantify the impact of retrofitting using an extensive measurement campaign. The window of the first room was provided with an installed glazing unit (SGU) i.e. single-glazed window. The window of the second room was retrofitted using the methods of the current invention wherein the single-glazed units were converted into triple- glazed units (TGU).

[0078] Various thermal measurements such as inside and outside surface temperatures, heat-flux sensors, inside air-temperature, mean radiant temperature, outdoor conditions (air- temperature, solar radiation), pyrometer (measurement of incident solar-radiation entering the glazing unit), wall-temperatures were taken over a period of one week. The results of the experiments are illustrated in FIG. 11 and FIG. 12. [0079] When the maximum inside surface temperature of the SGU reaches 36 °C, the maximum inside surface temperature in the TGU was found to be only 27 °C. Hence, retrofitting using the methods of the current invention brings down the inside surface temperature by about 9 °C.

[0080] Heat-ingress (Q_TGU) through the TGU is 3.3X less than the heat- ingress (Q_SGU) through the SGU as shown in FIG. 11.

[0081] Operative temperature (T_OP) is a measure of thermal comfort, where it measures a 'perceived' temperature by the occupant that includes both convection (effect of ambient air) and radiation (from heated surfaces and/or the sun). A_comf = % Area of the room for which Top is below a chosen threshold of 26.5 °C. Measurements of Top performed using a black-globe thermometer at these two points were compared with the calculations performed.

[0082] To illustrate thermal comfort, the operative temperature at all spatial locations in the room were calculated. Based on these calculations the area- fractions of the room that recorded T_OP > 26.5 °C (an arbitrarily chosen threshold) were estimated. For the room with a single-glazed window, more than 75 % of the area-fractions of the room had T_OP > 26.5 °C for roughly 6 to 7 hours during the day. In contrast, for a retrofitted room using the methods of the current invention, at least 84 % of the area-fractions of the room had a T_OP < 26.5 °C at any time during the day. Thus the retro-fitted room showed improved thermal comfort for all occupants in the room.

[0083] Note that not all of the activities described above in the general description or the examples are required, that a portion of a specific activity may not be required, and that one or more further activities may be performed in addition to those described. Still further, the order in which activities are listed is not necessarily the order in which they are performed.

[0084] Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any feature(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature of any or all the claims. [0085] The specification and illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The specification and illustrations are not intended to serve as an exhaustive and comprehensive description of all of the elements and features of apparatus and systems that use the structures or methods described herein. Certain features, that are for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in a sub combination. Further, reference to values stated in ranges includes each and every value within that range. Many other embodiments may be apparent to skilled artisans only after reading this specification. Other embodiments may be used and derived from the disclosure, such that a structural substitution, logical substitution, or another change may be made without departing from the scope of the disclosure. Accordingly, the disclosure is to be regarded as illustrative rather than restrictive.

[0086] The description in combination with the figures is provided to assist in understanding the teachings disclosed herein, is provided to assist in describing the teachings, and should not be interpreted as a limitation on the scope or applicability of the teachings. However, other teachings can certainly be used in this application.

[0087] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or inherent to such method, article, or apparatus. Further, unless expressly stated to the contrary, "or" refers to an inclusive-or and not to an exclusive-or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present). [0088] Also, the use of "a" or "an" is employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural, or vice versa, unless it is clear that it is meant otherwise. For example, when a single item is described herein, more than one item may be used in place of a single item. Similarly, where more than one item is described herein, a single item may be substituted for that more than one item.

[0089] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, methods, and examples are illustrative only and not intended to be limiting. To the extent that certain details regarding specific materials and processing acts are not described, such details may include conventional approaches, which may be found in reference books and other sources within the manufacturing arts.

[0090] While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

List of Elements

TITLE: SYSTEM AND METHOD FOR RETRO-FITTING GLAZING UNIT

100 Wall structure

102 Window frame

104 Installed glazing unit

106 Corner

108 Inner side

200 Installation system

201 Multiple glazing unit

202 Installation site

204 Secondary glazing unit

205 Corner

206 Periphery

207 Spacer element

208 First surface

210 Second surface

212 Inner surface

214 Outer surface

400 Fixture system

402 First fixture element

404 Second fixture element

406 First aperture

408 Second aperture

410 Extensions

412 Hole 414 Hole

418 Cavity

420 Clearance

424 Sealant

500 Sealant applicator

502 Thicker end

504 Thinner end

506 Central hole

508 Elongated channel

900 Method

902 Step

904 Step

906 Step

908 Step

Tl Thickness of secondary glazing unit

T2 Thickness of spacer element

LI Total length of thinner end

L2 Length of thinner end defining an elongated channel

Dl First offset

D2 Second offset

Claims

Claims What is claimed is:

1. A method of converting an installed glazing unit to a multiple glazing unit at an installation site, the method comprising:

providing, at the installation site, a secondary glazing unit and a spacer element, the spacer element having a first surface and a second surface opposite to the first surface, wherein the first surface is attached to the secondary glazing unit;

attaching a second surface of the spacer element to an inner side of the installed glazing unit; and

filling a sealant in a clearance between the installed glazing unit and the secondary glazing unit to bond the secondary glazing unit and the existing glazing unit to each other.

2. The method of claim 1, wherein the spacer element is attached to the installed glazing unit and the secondary glazing unit using an adhesive material.

3. The method of claim 1, wherein the spacer element is attached to the installed glazing unit and the secondary glazing unit using one of an acrylic foam adhesive, a butyl coated poly-vinyl chloride or a poly- isobutyl adhesive.

4. The method of claim 1, wherein the sealant includes a silicone based material.

5. The method of claim 1, wherein the sealant has a tensile strength of at least IMpa.

6. The method of claim 1 further comprising aligning the secondary glazing unit in a substantially parallel relationship to the installed glazing unit

- 1 - with the spacer element disposed between the installed and secondary glazing units.

7. The method of claim 1 further comprising disposing a moisture barrier on the spacer element.

8. The method of claim 7, wherein the moisture barrier is an aluminum foil.

9. The method of claim 1, wherein the spacer element includes a hygroscopic material.

10. The method of claim 1 further comprising:

disposing a first fixture element on each of the corners of the installed glazing unit;

disposing a second fixture element on each of the corners of the secondary glazing unit; and

coupling the first fixture element and the second fixture element.

11. The method of claim 1 further comprising:

disposing a thinner end of a sealant applicator in the clearance, the thinner end defining an elongated channel, the sealant applicator comprising a thicker end defining a central hole in fluid communication with the elongated channel;

supplying the sealant through the central hole; and

moving the sealant applicator to fill throughout the clearance, wherein the sealant is received from the central hole and the elongated channel.

12. An installation system for converting an installed glazing unit to a multiple glazing unit at an installation site, the installation system comprising:

a secondary glazing unit;

- 2 - a spacer element having a first surface and a second surface opposite to the first surface, the first surface configured to be attached to the secondary glazing unit and the second surface configured to be attached to an inner side of the installed glazing unit;

a sealant; and

a sealant applicator configured to allow a flow of the sealant to a clearance between the installed glazing unit and the secondary glazing unit, the sealant applicator comprising:

a thicker end defining a central hole configured to receive the sealant therethrough; and

a thinner end configured to be removably inserted in the clearance, the thinner end defining an elongated channel that is in fluid communication with the central hole and further configured to fill the clearance with the sealant received via the central hole and the elongated channel.

13. The installation system of claim 12, wherein the elongated channel defined in the thinner end has an oval shape.

14. The installation system of claim 12, wherein the sealant applicator further defines a draft having a uniform cross-sectional area, wherein the draft is fluidly connecting the elongated channel with the central hole.

15. The installation system of claim 12, wherein the spacer element is made of one of a aluminum or a poly-carbonate based material.

16. The installation system of claim 12, wherein the spacer element further comprises a moisture barrier disposed thereon.

17. The installation system of claim 12, wherein the sealant is a silicone based adhesive.

- 3 -

18. The installation system of claim 12 further comprising a tool for supplying the sealant to the central hole of the sealant applicator.

19. The installation system of claim 18, wherein the tool is one of an electrically pressurized tool or a pneumatically pressurized tool.

20. The installation system of claim 12 further comprising:

a first fixture element configured to be disposed on at least one corner of the inner side of the installed glazing unit;

a second fixture element configured to be disposed at a corresponding corner of the second glazing unit, wherein the second fixture element and the fixture element are configured to be coupled to each other.

21. The installation system of claim 20, wherein the first fixture element defines a first aperture therethrough and the second fixture element defines a second aperture therethrough, wherein the first aperture and second aperture are configured to co-axially align with each other so as to align the secondary glazing unit generally parallel to the installed glazing unit.

22. The installation system of claim 12 further comprising a hygroscopic material contained in the spacer element.

23. The installation system of claiml2, wherein the multiple glazing unit is resistant to moisture and condensation.

24. A sealant applicator for filling a sealant in a clearance between two glazing units that are attached to each other, at least one of the two glazing units installed in a frame , the sealant applicator comprising: a thicker end defining a central hole for receiving the sealant therethrough; and

- 4 - a thinner end configured to be removably inserted in the clearance, wherein the thinner end defining an elongated channel is in fluid communication with the central hole and further configured to fill the clearance with the sealant received from the central hole and the elongated channel.

25. The sealant applicator of claim 24, wherein the elongated channel has an oval shape.

26. The sealant applicator of claim 24, further defines a draft therethrough fluidly connecting the elongated channel with the central hole, wherein the draft is configured to provide uniform velocity therethrough.

27. The sealant applicator of claim 26, wherein an area of the draft at any cross-section is equal to an area of the central hole.

28. The sealant applicator of claim 24 further configured to receive the sealant via one of an electrically pressurized tool or a pneumatically pressurized tool.

29. The sealant applicator of claim 24, wherein the sealant is a silicone based adhesive.

30. A fixture system for adding a secondary glazing unit to an inner side of an installed glazing unit that is attached to a window frame, the fixture system comprising:

a first fixture element configured to be disposed on at least one corner of the inner side of the installed glazing unit, wherein the first fixture element defines a first aperture therethrough;

a second fixture element configured to be disposed on a corresponding corner of the second glazing unit, the second fixture element defining a second aperture therethrough, wherein the first and second fixture elements are configured to align the secondary glazing unit

- 5 - generally parallel to the installed glazing unit by co-axially aligning the second aperture with the first aperture.

31. The fixture system of claim 30 configured to transfer a load from the installed glazing unit to the window frame.

32. The fixture system of claim 30, wherein the first fixture element and the second fixture element are configured to be coupled to each other.

33. The fixture system of claim 30, wherein each of the first fixture element and second fixture element define a plurality of holes therethrough to allow the flow of an adhesive therethrough, the adhesive being filled in a clearance between the installed glazing unit and the secondary glazing unit.

34. A multiple glazing unit comprising:

a window frame attached to a wall structure;

an installed glazing unit having an inner side and attached to the window frame;

a secondary glazing unit added to the inner side of the installed glazing unit in a substantially parallel and spaced apart relation from the installed glazing unit;

a spacer element disposed between the installed glazing unit and the secondary glazing unit;

a weather resistant sealant disposed in a clearance between the installed glazing unit and the secondary glazing unit;

a first fixture element disposed on at least one corner of the inner side of the installed glazing unit; and

a second fixture element disposed on a corresponding corner of the secondary glazing unit, wherein the second fixture element and the first fixture element are coupled to each other.

- 6 -

35. The multiple glazing unit of claim 34, wherein the weather resistant sealant is a silicone based sealant.

36. The multiple glazing unit of claim 34, wherein the spacer element is made of one of an aluminum or a poly-carbonate based material.

37. The multiple glazing unit of claim 34, wherein the spacer element further comprises a moisture barrier disposed thereon.

38. The multiple glazing unit of claim 34, wherein the spacer element contains a desiccant therein.

39. The multiple glazing unit of claim 34 having a property of condensation resistance.

40. The multiple glazing unit of claim 34, wherein the first fixture element and the second fixture element are configured to transfer a load from the installed glazing unit to the window frame.

41. A system for improving energy efficiency and thermal comfort of a building, the system comprising

a window frame attached to a wall structure;

a sealant disposed using a sealant applicator in a clearance between the installed glazing unit and the secondary glazing unit;

- 7 - a second fixture element disposed on a corresponding corner of the secondary glazing unit, wherein the second fixture element and the first fixture element are coupled to each other.

42. The system of claim 41, wherein the maximum inside surface temperature recorded in a building retrofitted with one or more secondary glazing units is about 5 to 15 °C less than the maximum inside surface temperature recorded by a building having an installed glazing unit.

43. The system of claim 41, wherein the heat- ingress of a building retrofitted with one or more secondary glazing units is about 3.3x less when compared with a building having an installed glazing unit.

44. The system of claim 41, wherein about 70% to 90% of area- fractions of a building retrofitted with one or more secondary glazing units records an operative temperature (T_OP) of less than < 26.5 °C.

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