1. Field of the Invention
This invention is directed to materials and methods for sealing windows and other fenestration products from moisture intrusion.
2. Description of Related Art
Flanges or nailing fins on windows, doors and other fenestration products, in which the flange is integral to and continuous with the window frame, provide a surface that is fully connected to the window for adhesive flashing materials to adhere to, enabling the flashing product to create a continuous watertight seal at the window-wall interface in structures, such as buildings. However, flanges are not present in all windows or fenestration products (hereinafter referred to as “windows”). Non-flanged windows and windows with brickmold frames (hereinafter referred to as “brickmold windows”) are prone to moisture intrusion, due to difficulty in achieving a continuous flashing integration between the window and the wall. Thus, the typical installation method for these types of windows involves a bead of building sealant between the fenestration product and the wall, which is not a durable, continuously integrated moisture seal and is prone to failure after environmental exposure. This results in a higher tendency for moisture damage to the window and the surrounding wall, including rot and mold growth. No known methods exist to install non-flanged and brickmold windows in a way that effectively seals the window-wall interface with a continuous integration of self-adhered flashing to prevent moisture intrusion. It would be desirable to have a product and window installation method, which would integrate the window-wall interface in window systems using windows without flanges.
In addition, applied rigid flanges, which may or may not be integral to the window, can be problematic in sealing the window-wall interface due to bending or cracking of the flange, or poor joint sealing. It would be desirable to have a product and window installation method that would obviate the need for rigid flanges.
This invention is a self-adhering flange material for sealing interfaces between fenestration products and walls, comprising at least one top coversheet and at least one bottom coversheet with a pressure-sensitive adhesive layer sandwiched between the two coversheets, wherein the coversheets occupy an appreciable width of the flange but do not extend across the entire width of the flange and thereby are offset with respect to each other thereby providing opposing first and second exposed surfaces of the pressures sensitive adhesive layer.
This invention is also encompasses various methods for installing fenestration products into walls using the subject flange material.
The term “flanged windows” refers to windows, doors, or other fenestration products that include a flange or nailing fin intended to cover any space between the window frame and the rough opening in the wall. The flange or fin may be integral to the fenestration product, or may be applied.
The term “non-flanged windows” refers to windows that do not include a flange intended or nailing fin to cover the space between the window frame and the rough opening in the wall.
The term “brickmold frame” refers to decorative trim attached to or integral to the window frame that covers any space between the window frame and the opening in the wall into which the window is installed. The term “brickmold window” refers to a window having a brickmold frame.
The term “window jamb” or “jamb” refers to the side of the window frame. The window jamb is typically vertical.
The term “windowsill” or “sill” refers to the bottom portion of the window frame. The windowsill is typically horizontal.
The term “window head” or “head” refers to the top portion of the window frame. The window head is typically horizontal.
The term “window” refers to any window, door, or other fenestration products intended to be installed in an opening in a wall.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate, without limitation, the presently contemplated embodiments of the invention and, together with the description, serve to explain the principles of the invention.
The flange material of this invention can be applied to all non-flanged windows, brickmold windows, and windows having applied flanges to form a self-adhering flange that provides a means for achieving a continuous moisture seal integration of the window-wall interface. The flange additionally prevents moisture from entering around fasteners, such as nails, that penetrate the flange material and the window frame. As further described below in various installation methods, pieces of flange material are positioned at the window wall interface to form the flange. Upon installation, the flange typically comprises a headpiece of flange material positioned at the top of the window-wall interface and two jamb pieces of flange material positioned at the sides of the window wall interface.
As depicted in
If desired, the flange material can be fabricated in the field. For example, flange material 20 as shown in
There is a method for installing a non-flanged window into a wall opening whereby the interface between the window and the wall is sealed using either of the flange materials described above in FIGS. 1 or 3. The method described as follows uses the flange material of
The window is thereby sealed to the surrounding wall and any water that contacts the outer surface of the headpiece will be directed downward below the top of the jamb pieces so that there is virtually no opportunity for the water to penetrate the window-wall interface.
Another embodiment of the invention is useful for sealing brickmold windows. According to this embodiment as shown in
One method for installing a brickmold window into a wall opening whereby the interface between the window and the wall is sealed is described in the following steps as Brickmold Method 1. This method may also be applied to windows having integral and applied flanges. The window is sealed by means of a flange material as shown in
Another method for installing a brickmold window frame into a wall opening is designated as Brickmold Method 2, whereby the interface between the window and the wall is sealed includes the following steps. Again, this method may be used to install windows having integral and applied flanges. In this method, the flange is prepared first, and then attached to the window before the window is installed. The flange material as depicted in
The method for installing a brickmold window frame using the aforementioned flange is described as follows and illustrated in
A length of the flange material (the “head flange” 311), advantageously several inches longer than the width of the brickmold frame, is folded along one of the perforations 19 in the release paper to expose a line of adhesive as between 18a and 18a′.
The line of adhesive is positioned in the corner along the top of the window frame between the back surface 323 of the brickmold frame and the upper surface 321 of the window head.
The flange material may be applied to the window during window fabrication. In this case, the window could be provided as it is at the end of step (i) above, and the remaining steps (j) through (m) would be carried out, for example, by the installers at a building site.
In each of the previous embodiments, the pressure sensitive adhesive used in the flange material of the invention can be butyl rubber adhesive, bituminous adhesive, acrylic, or combinations thereof (layers or blends). Additionally, the pressure sensitive adhesive can be neoprene, polymers based on epdm (ethylene propylene diene monomer), or other adhesives generally used in construction applications. The thickness of the pressure sensitive adhesive is between about 15 mils (0.38 mm) and 25 mils (0.64 mm). The pressure sensitive adhesive provides a watertight seal around fasteners that penetrate the flange material.
The material used as the coversheet material in the flange material of the invention can be any nonwoven sheet, film, coated paper, coated nonwoven sheet, or nonwoven-film laminate suitable for use in a flexible flashing material. The coversheets can be polyolefin plexifilamentary film-fibril sheet, available under the trade name Tyvek® from DuPont.
Alternatively, the coversheet of the flange can be made from a relatively rigid material such as metal or plastic formed into the required shape for the various installations noted above. The rigid material would have a pressure-sensitive adhesive layer applied to provide attachment to the windows and building structure.
As will be appreciated by the skilled artisan, although reference is made herein to adhering the flange material to a wall, it is also expected that the flange material of the invention can be adhered to a wall covered by a weather resistive barrier sheet.
It may be further appreciated that the flange can likewise include a sill piece appropriately installed to form a total barrier system around the wall-window interface. to further preclude moisture intrusion.
The installations were tested for air leakage using ASTM E 283.
The installations were tested for water resistance using ASTM E 331.
The durability of the selected installations was then evaluated by subjecting the walls first to thermal cycling and re-testing for air leakage and water resistance, and secondly by subjecting the walls to wind load using ASTM E 330 for one hour in the positive direction and one hour in the negative direction, and then re-testing for water resistance. The thermal cycling of exterior walls was conducted according to AAMA (American Architectural Manufacturers Association) 501.5. Standard Test Method for Exterior Windows, Curtain Walls, and Doors for Water Penetration using Dynamic Pressure.
A series of laboratory tests was designed to determine water resistance, air leakage resistance, and durability of installation using different methods and different flashing materials. Installations were carried out installing JELD-WEN® double hung wood windows (available from JELD-WEN, Klamath Falls, Oreg.) with applied brickmold frames into wood frame walls. The testing was conducted in two phases. First, air and water resistance of window installations were evaluated. Secondly, air and water resistance were evaluated after thermal cycling followed by wind loading.
Four test walls were constructed for the testing. All four walls were constructed using Spruce-Pine-Fir nominal 2 in×4 in lumber and covered with oriented strand board sheathing applied to 16 in on center studs. All walls were 5 ft wide by 7 ft 6 in high and contained one brickmold window unit. The window used in each case was a JELD-WEN® wood double hung window with applied brickmold. The windows were each 2 ft 10 in wide×3 ft 4 in high. Four different flashing installations methods were utilized as described below in Examples 1-4.
A wall unit as described above was wrapped with Tyvek® HomeWrap® (available from E. I. du Pont de Nemours and Company, Wilmington, Del.) prior to installing the window. DuPont FlexWrap™ (available from E. I. du Pont de Nemours and Company) was installed on the sill per normal installation procedures recommended by the manufacturer and an adhesive foam tape was installed under the DuPont FlexWrap™ to form a back dam.
In this installation, 4 in wide DuPont StraightFlash™ (available from E. I. du Pont de Nemours and Company) flashing having three perforated sections of release paper was the primary part of the flange material system. Head and jamb pieces of DuPont StraightFlash1υ were installed on the head and sides of the window prior to installation of the window into the rough opening, using the above-described Brickmold Method 1.
With the final pieces of the release liner still covering the adhesive on the flashing installed on the brickmold window frame, the window was installed per manufacturer's recommended procedure. Next, the final pieces of release paper remaining on the window were removed, exposing a strip of butyl adhesive on the exterior of the wall adjacent the window on each side. Next, another covering piece of 4 in wide DuPont StraightFlash™ flashing with similarly perforated release paper was applied over this as follows. One of the release papers along the edge of the flashing was removed, and the edge of the exposed butyl was placed flush adjacent the corner between the outer surface of the brickmold frame and the exterior surface of the wall such that the edge of the butyl touched the inside of the corner. Once the butyl edge adhered to the inside corner, the rest of the exposed butyl strip was laid down onto the already installed, exposed butyl strip adjacent the window. This created a very strong butyl-to-butyl seal. This seal created the flange material.
The procedure for installing a covering piece of flashing was repeated on other side of the window.
Finally, the flange material system was completed and integrated into the wall by removing the last two strips of release paper from the covering pieces of flashing and laying the exposed butyl adhesive smoothly onto the exterior wall surface to complete the seal of the window-wall interface.
A metal drip cap was installed and the DuPont StraightFlash™ was installed over the drip cap followed by a flap of the previously installed Tyvek® HomeWrap®. The Tyvek® HomeWrap® was taped over the drip cap and tape was applied in a shingled fashion to avoid leakage.
Air and water resistance of this window installation are given in Table 1. Air and water resistance after thermal cycling and water resistance after wind loading of this window installation are given in Table 2.
A wall unit as described above was wrapped with Tyvek® HomeWrap® prior to installing the window. DuPont FlexWrap™ was installed on the sill and an aluminum angle was installed under the DuPont FlexWrap™ to serve as a back dam.
The flange material was prefabricated by attaching two 4 in wide pieces of DuPont StraightFlash™ together. The flange material was installed on the window at the window head and then the jambs.
The window was installed using Brickmold Method 2 and the final pieces of release papers were removed and adhered to the Tyvek® HomeWrap™. The remaining exposed butyl on the top flange was cut away and the remaining exposed flange area was covered with a 6 in to 8 in long piece of 4 in wide DuPont StraightFlash™.
Air and water resistance of this window installation are given in Table 1. Air and water resistance after thermal cycling and water resistance after wind loading of this window installation are given in Table 2.
A wall unit as described above was wrapped with Tyvek® HomeWrap® after the window was installed. DuPont FlexWrap™ was installed on the windowsill and an aluminum angle was installed under the DuPont FlexWrap™ to serve as a back dam. The flange material was prefabricated by attaching two 4 in wide pieces of DuPont StraightFlash™ together. The flange material was installed on the window jambs. At the head of the window, a 4 in wide piece of DuPont StraightFlash™ was adhered to the top of the window frame and the back of the decorative brickmold with the final piece of release paper facing out above the decorative brickmold using Brickmold Method 2.
The window was installed, then the rest of the release paper on the flange material was removed and the flange material was adhered to the wall. A drip cap was installed at the head of the window and a piece of DuPont StraightFlash™ was placed over the drip cap. Then the wall was wrapped with Tyvek® HomeWrap® and the joints were taped.
Air and water resistance of this window installation are given in Table 1. Air and water resistance after thermal cycling and water resistance after wind loading of this window installation are given in Table 2.
The window was installed into a wall unit as in Example 2 (that is using Brickmold Method 2) except that the wall unit was wrapped with Tyvek® HomeWrap® after the window was installed. The flange material for the head was fabricated in a “T” configuration by cutting a smaller piece of flashing the width of the window frame and centering it on a relatively larger piece of flashing.
Air and water resistance of this window installation are given in Table 1. Air and water resistance after thermal cycling and water resistance after wind loading of this window installation are given in Table 2.
1Water laying on front edge of sill plate.
2Water percolating at right side of bottom corner of sill plate.
3Water entered at the right side interior windowsill leg.
In both Tables 1 and 2 cfm means cubic feet per minute and psf means pounds per square foot.
None of the leaks observed involved the installed flange material of the invention. None of the leaks were considered to be significant. In all examples, even after static load testing, the water did not get past the installed flange material of the invention to the interior plane of the installed window. These results demonstrate the durability of the flange in use.