US20090084047A1

US20090084047A1 - Closed cell polyethlene furring strips and house wrap with closed cell polyethylene furring strips

Info

Publication number: US20090084047A1
Application number: US12/292,707
Authority: US
Inventors: Mark F. Williams
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-11-21
Filing date: 2008-11-25
Publication date: 2009-04-02

Abstract

There is disclosed a furring strip system wherein furring strips serve to provide a space to promote drainage and drying between the exterior siding or cladding and the underlying construction. These furring strips may be pre-attached to at least one side of a water resistive barrier (WRB—sometimes referred to as “Housewrap”) Additionally, it has been found that the use of closed cell polyethylene foam furring strips significantly reduces the amount of water penetration and leakage that occurs along the fasteners through the furring strips and the WRB onto the unprotected sheathing therebeneath, i.e. the closed cell foam furring strips provide a “gasketing effect”, and “self-sealing” as the fastener, whether it be a staple or nail, penetrates the closed cell polyethylene foam furring strip. The usefulness of the invention is the same regardless of whether the furring strips are pre-attached to the WRB or are added before or after the WRB has been applied to the building structure. It has been found that once the closed cell furring strips have been installed, all subsequent wall components should be attached with fasteners that penetrate the closed cell polyethylene furring strips and receive the gasketing effect thereby.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application is a Continuation-in-part of Ser. No. 11/283,082, entitled, House Wrap With Integral Furring Strips, filed on Nov. 21, 2005, by the same inventor as the instant application, Mark F. Williams.

BACKGROUND OF THE INVENTION

The present invention relates to exterior walls of building structures, primarily light frame construction, wherein specific measures have been taken to ensure that the sheathing, framing and other underlying components are protected from the effects of prolonged exposure to elevated levels of moisture which can cause damage, including deteriorated materials, structural rot, mildew formation and mold or mold spores that may penetrate into the interior of a structure and cause adverse health consequences for the occupants thereof.
Over the years there have been serious attempts to minimize the above noted problems relating to water penetration through the exterior walls of a building structure. One product which has been used to protect the sheathing and underlying framing is a Water or Weather Resistive Barrier (WRB). A WRB is applied in close contact over the sheathing of a building structure.
If water finds its way behind the WRB, i.e. onto the sheathing side of the WRB, it is often held by the WRB against the sheathing. This may lead to even more profound damage because this water is often prohibited from draining away and the exposed areas are prohibited from drying properly.
Research indicates that one way to restrict water from getting behind the WRB and promote drying is to provide a dedicated space (capillary break) on one or both sides of the WRB. This provides a space for drainage/drying between the cladding and WRB and/or WRB and sheathing. WRBs alone often do not provide adequate protection unless this dedicated space is provided. This space can be created by using furring strips, drainage mats or drainage boards. If cement based materials are applied in a liquid state, such as stucco or the scratch coat for manufactured stone veneer, a separation sheet is required in conjunction with these products to insure the integrity of the space. (The assembly which includes this space is often referred to as a rainscreen.)
Another way to restrict water from getting behind the WRB is to provide a “gasket” or seal around penetrations where they pierce the WRB. Cap nails and cap staples gasket effectively at the point where the fasteners penetrate the WRB because the cap is in contact with the WRB. Cap nails and staples are effective for attaching the WRB, but penetrations caused by attaching additional wall elements including related components such as rainscreen components, siding (vinyl, aluminum, wood, or cement board), and lath (required for stucco and manufactured stone) create penetrations through the WRB, which are not gasketed, thus providing a source of leakage. Research indicated that these penetrations are pathways for significant amounts of water to get behind the WRB into intimate contact with the sheathing.

SUMMARY OF THE INVENTION

The present invention reduces the amount of water penetration that is transferred through the exterior walls of a building structure that utilizes any Water Resistive Barrier (WRB) sheet material or housewrap such as TYVEK® that is secured to the sheathing of a building by means of furring strips that are made of closed cell polyethylene foam material. It has been found through experimentation that furring strips create a space to promote drainage and drying and that the use of closed cell polyethylene foam furring strips significantly reduces the amount of water penetration and leakage that occurs along the fasteners through fastener punctures of the furring strips, the WRB, and the sheathing therebeneath, i.e. the closed cell foam furring strips provide a “gasketing effect”, and “self-sealing” as the fastener penetrates the closed cell polyethylene foam furring strip. The usefulness of the invention is the same regardless of whether the furring strips are pre-attached to the WRB or are added before and/or after the WRB has been applied to the building structure. These furring strips are inert and therefore are unaffected by moisture. They are flexible which allows them to be pre-attached to a WRB or a separation sheet to facilitate easier installation. This flexibility also allows these furring strips to be extruded in a continuous length and coiled up for easy handling and shipping. These continuous lengths also facilitate easier installation as will be described hereinafter.
It has been found through experimentation that the use of extruded closed cell polyethylene foam furring strips significantly reduces the amount of water and leakage that occurs along the fasteners through fastener punctures of the foam furring strips and the WRB where the foam furring strip is in contact with the WRB. The closed cell foam furring strips provide a “gasketing effect” and “self-sealing” as the fastener penetrates the closed cell foam and the WRB where the closed cell foam is in contact with the WRB. All fasteners should pass through the extruded cell foam furring strips to prohibit water from penetrating the WRB at fastener penetrations.
The usefulness of the invention in providing “gasketing” at penetrations is the same regardless of whether the furring strips are pre-attached to the WRB or applied to the WRB during construction of the building on one or both sides of the WRB. A further advantage of the closed cell polyethylene foam furring strips is the fact that the closed cell foam furring strips restrict the transfer of heat.

DISCUSSION OF KNOWN PRIOR ART

A search of the Patent Office files in the appropriate Class and subclasses revealed the following prior art.
U.S. Pat. No. 6,938,383—issued to Richard J. Morris et al on Sep. 6, 2005—discloses a vented furring strip that is used to ventilate the area between the sheathing of a residence and the exterior siding or cladding and eliminate any moisture or water from therebetween. The elongate furring strips are installed as separate pieces on the first layer of a wall and covered with an exterior siding. The furring strips space the siding apart from the sheathing, forming a plurality of enclosed cavities or air spaces. The cavities are in fluid communication with each other through air passages in the furring strips that extend transversely to a longitudinal axis of the furring strip, i.e. these passages through the furring strips are horizontally disposed and serve to connect the cavities that are formed between adjacent furring strips thus providing ventilation of the entire area. By allowing air to enter the cavities between adjacent furring strips, there is a total or complete ventilation of the area between the sheathing and the exterior siding, thus the problems associated with water and moisture such mildew, rotting, mold and mold spores becomes moot.
U.S. Pat. No. 6,357,193—issued to Richard J. Morris on Mar. 19, 2002—discloses a roof batten for use in spacing tiles or similar exterior roofing members from a roof overlayment. This “batten” is structurally the same as the “furring strips” referred to in Morris, '383 immediately above.
U.S. Pat. No. 6,267,668—issued to Richard J. Morris on Jul. 31, 2001—discloses a roof vent formed by utilizing a pair of spaced ventilation devices 50 that are advantageously disposed between installed sheets 20 and ridge cap 22 to insure that air exchange proximate peak 14 between the interior and exterior of roof will occur within vent 50.
These three references disclose ventilated furring strips, batten strips, and ridge vent spacer strips, they each rely on cavities that are within the strips that are transverse to the longitudinal axis of the various strips. These three references do not call for the furring strips to be of a flexible material. Further, these three patents are all directed to the use of furring strips installed individually in the field whereas the subject matter of the instant invention provides a series of furring strips that are pre-attached to at least one side, and preferably both sides of conventional water resistive barrier sheet material (WRB) in the factory and automatically spaced and installed when the WRB is installed in the field. There is no specific mention of the material that the furring strips are made of. In the instant application, the individual furring strips are made of extruded closed cell polyethylene foam material which provides the a “self-sealing” feature when punctured and penetrated by a fastener that is utilized in securing the furring strip, WRB attachment, or cladding component to the building structure, thus reducing the amount of water that would penetrate the WRB and furring strip and come into contact with the sheathing therebeneath.

OBJECTS OF THE INVENTION

An object of the invention is to provide a water resistive barrier (WRB) with furring strips that are either pre-attached to the WRB or attached in the field.
A further object of the invention is to provide a WRB with furring strips that are made of closed cell polyethylene foam material.
A still further object of the invention is to provide furring strips that are provided in extruded closed cell polyethylene roll form.
Another object of the invention is to provide a furring strip that will minimize the transfer of heat to and from the interior of a building structure.
A further object of the invention is to provide an extruded closed cell polyethylene foam furring strip that serves to gasket fasteners utilized for securing WRB as well as subsequent wall elements such as siding, building paper and metallic lath.
A still further object of the invention is to provide extruded closed cell polyethylene foam furring strips that are utilized in the attachment of WRB as well as building paper and metallic lathe that are sequentially applied in a stucco finished exterior.
Yet another object of the invention is to provide a water resistive barrier (WRB) that utilizes furring strips that are self-sealing when penetrated by fasteners utilized to secure the furring strips to a building structure.
Another object of the invention is to provide gasketing or sealing of fastener penetrations to attach the WRB or separation sheet when those fasteners pass through the closed cell foam furring strip.
A further object of the invention is to provide gasketing or sealing where fasteners for siding, lath and other wall components penetrate the WRB by installing fasteners through the closed cell foam furring strips.
Yet another object of the invention is to provide an easy installation of foam furring at the construction site by providing the foam furring in continuous lengths so that one length will span the height of the wall and can be installed in one step rather than needing to install a plurality of lesser length pieces.
These and other objects of the invention will become more apparent hereinafter. The instant invention will now be described with reference to the accompanying drawings wherein like reference characters designate the corresponding parts throughout the several views.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a house wherein the furring strips have been attached to the water resistive barrier (WRB) sheet material prior to the installation of the WRB sheet material to the building.

FIG. 2 is an illustration of a roll of WRB with the furring strips pre-attached to both sides of the WRB sheet material.

FIG. 3 is a sectional view taken along the plane 3-3 of FIG. 2, illustrating the internal structure of the closed cell foam polyethylene furring strip.

FIG. 4 is an illustration of the pressure chamber mock-up according to ASTM E-514, that was used in testing the effectiveness of the closed cell polyethylene furring strips.

FIG. 5 is an enlarged view of the oval labeled “5-5” in FIG. 1, illustrating the surface self-sealing attributes of the closed cell foam polyethylene furring strip when penetrated by securing nails.

FIG. 5A is a sectional view taken along the plane 5A-5A of FIG. 5, illustrating securement of the strip by a nail.

FIG. 6 is an enlarged view of the oval labeled “6-6” in FIG. 1, illustrating the surface self-sealing attributes of the closed cell foam polyethylene furring strip when punctured by staples.

FIG. 6A is a sectional view taken along the plane 6A-6A of FIG. 6 illustrating the gripping effect on a securing staple.

FIG. 7 is an illustration of an extruded closed cell polyethylene foam furring strip material in roll form.

FIG. 8 is an enlarged view of the oval labeled 8-8 in FIG. 1, showing the attachment of exterior siding over the extruded closed cell polyethylene furring strips.

FIG. 9 is a detailed view, similar to that of FIG. 8, illustrating the sequence of application of layered components applied over the WRB and extruded closed cell polyethylene furring strips when applied to a stucco finish residence.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to FIG. 1, there is illustrated a house 50 having an attached garage 51 with siding 51S thereon. As shown, house 50 is wrapped with a water resistive barrier 60, which will be referred to as WRB hereinafter, that includes a plurality of furring strips 61 attached to both sides of WRB sheeting material 60. However, only the outer side is shown in this view with the furring strips 61 aligned, as successive rows of WRB 60 are applied to the house 50. As noted n FIG. 1, the lowermost row of WRB 60 begins at the lowermost right-hand side of house 50 with furring strip 61 aligned with the right end of the exterior sheathing and flap.
FIG. 2 is an illustration of the furring strips 61 that have been factory attached to opposite sides of WRB sheet material 60. Also shown in FIG. 1 are top flap 60TF and right flap 60RF portions that play an important part in the “overlapping” of successive rows of WRB when being applied to the building structure. Furring strips 61 are positioned on both sides of the WRB with the sides offset vertically from each other, thus leaving a top flap portion 60TF and a bottom flap portion 60BF on the respective sides thereof. This feature facilitates proper overlapping of successive rolls 61 as shown in FIG. 1.
FIG. 3 is a sectional view taken along the plane 3-3 in FIG. 2. This figure illustrates the roll of WRB sheet material 60 with the closed cell polyethylene foam furring strips 61 attached to both sides of the water resistive barrier (WRB) sheet material 60. The furring strips 61 have been placed directly opposite to each other on opposite sides the WRB 60.
FIG. 4 is an illustration of the mock-up utilized in testing the effectiveness of the “closed cell furring strips”. This mock-up is illustrated and described in a publication entitled, BUILDINGS X CONFERENCE DEC. 2-7, 2007, 11 ppg, the contents of which is hereby incorporated herein by reference. As illustrated in FIG. 4, a pressure chamber 150 was built large enough to accommodate two mock-ups, 151, 152, placed side by side within pressure chamber 150. This pressure chamber 150 is constructed of plywood sheathing on wood studs, and is 8 ft. (244 cm) wide, 5 ft. (183 cm) high, and 2 feet (61 cm) deep. A central partition 153 subdivides the interior chamber space, except for a 3 in. (8 cm) gap at the bottom to allow airflow between the two mock-ups. 151,152. The front side includes two 40 in. (102 cm)×45 in.(114 cm) openings which are covered with clear acrylic sheet panels, left acrylic panel 157L and right acrylic panel 157R, to allow observation during testing. Acrylic panels 157L and 157R are mounted to the front face of pressure chamber 150 by means of a plurality of screws 157A. Also shown are a plurality of spaced water spray racks 158, each of which, includes a pair of spray nozzles 159 through which water, at a controlled pressure and spray intensity is directed onto the furring strips 61.
The water is allowed to drain into the bottom of the pressure chamber 150 for recirculation. In addition to the controlled spraying of water on the mock-ups, additional equipment, such as a variable speed blower, flowmeter and manometer are mounted externally of pressure chamber 150 and illustrated along with associated piping at the left end thereof.
Each mock-up was installed in the chamber 150 and sealed in place with self-adhering membrane and mastic. Water was applied to the front face of each mock-up from a spray rack 158 and was delivered through an adjustable spray head 159. Water was monitored by a digital flowmeter, and the rack 158 was calibrated to deliver the required quantity of water at the required application rate. The bottom portion of both mock-up areas 157L, 157R was provided with drain outlets. Air pressure was applied with a variable speed blower and monitored by a manometer. The flowmeter, blower, and manometer were all mounted at one end of the pressure chamber 151 and are visible at the left-hand end portion of FIG. 4, as indicated at 160.
The typical 3 ft.×4 ft. (01 cm 121 cm) mock-up was constructed as follows. Each mock-up included 2 ft.×4 ft. 961 cm×121 cm) wood frame construction, covered with 7/16 in. (11 mm) oriented strand board (OSB). The OSB includes two removable panels, which were fitted side by side within the 2 ft.×4 ft. (61 cm×121 cm) frame. To help document water intrusion pathways, the front surface of the sheathing was previously coated with a marker dye powder that changes color on contact with moisture. The sheathing was then covered with the WRB material(s), which were attached with ⅜ in. (9.5 MM) staples placed 8″ (204) on center,
FIG. 5 is an enlarged illustration of the subject matter within oval 5-5 of FIG. 1. This figure clearly illustrates the manner in which the fastener, a nail 155, is grippingly engaged by the closed cell polyethylene foam furring strip 61, thus preventing the penetration of moisture and water along the nail shank 155S and preventing entry into the building structure.
FIG. 5A is a sectional view taken along the plane 5A-5A through FIG. 5 illustrating the “gripping effect” the closed cell polyethylene foam exerts on the nail head 155H and shank 155S, on both the top and bottom of furring strips 61 thus preventing any water migration therealong.
FIG. 6 is another view similar to FIG. 5, however, this view illustrates the subject matter shown within oval 6-6, illustrating the manner in which the fastener, a staple 156, is grippingly engaged by the closed cell polyethylene foam furring strips 61, thus preventing the penetration of moisture and water along the leg 156L of the staple and preventing entry into the building structure.
FIG. 6A is a sectional view taken along the plane 6A-6A of FIG. 6. This figure clearly illustrates the cooperative effort taking place between the staple 156 and the extruded closed cell polyethylene foam furring strips 61, thus preventing the migration of water along the staple leg 156L into the building structure.
FIG. 7 is an illustration of the extruded closed cell polyethylene foam furring strip material in roll form 61R. The production of the extruded closed cell polyethylene foam furring strip 61 in roll form 61R as indicated has several distinct advantages. Firstly, production of the furring strip 61R in roll form has the advantage of compactness for shipping and storage and handling purposes. Secondly, furring strip 61 in roll form has the unique advantage of ease of installation i.e. the installer merely grabs the free end of the roll and climbs to the highest part of the building where the furring strip 61R is to be installed, and by gravity, release of the furring strip 61 aligns itself vertically for easy stapling to the building structure by the installer, thus eliminating the need for cutting the closed cell foam roll 61R into individual furring strip lengths.
In view of the above, it is clearly seen that the closed cell extruded polyethylene foam furring strip, in its roll form 61R, is useful with WRBs, such as TYVEK®, or any of the other commercially available water resistive barriers presently available. In such instances, the furring strips 61R may be applied to the house directly onto the sheathing, before the WRB, or it may be installed over after the WRB.
FIG. 8 is an illustration of the subject matter shown within the oval 8-8 of FIG. 1, showing the attachment of siding 51S with fasteners 156, nails or staples, that are anchored through furring strips 61. In this view, it is seen that the fasteners, nails 155, first penetrate siding 51 before entering furring strip 61 where the extruded closed cell furring strip serves to seal and gasket nails 155.
FIG. 9 is an illustration of the manner in which additional layers of related wall components are attached to a building structure when the exterior is a stucco finish 64. As shown, a layer of building paper 62 is applied over the WRB 60 and furring strips 61 with the staples 156 being driven into the furring strips 61 to secure the building paper 62 in place. Next, the metallic lath 63 is layered over the building paper 62, again, the metallic lath 63 is attached by means of staples 156 through the metallic lath 63 into furring strips 61, followed y the application of the required number of layers of stucco.
While the invention has been described in its preferred embodiment, it is to be understood that the words that have been used are words of description rather than words of limitation and the changes may be made within the purview of the appended claims without departing from the full scope or spirit of the invention. Accordingly, the present invention is to be limited only by the appended claims, and not by the forgoing specification.

Claims

1. A water resistive barrier (WRB) for use in frame construction wherein

said WRB ensures drainage and drying of unwanted water between the main structure and exterior siding of a building;

said WRB comprising;

flexible water resistive barrier sheet material;

said flexible water resistive barrier sheet material having a plurality of spaced furring strips on at least one side thereof;

said furring strips fabricated from closed cell polyethylene foam material which inhibits water intrusion where construction fasteners are installed through said closed cell polyethylene foam furring strips; and

said WRB sheet material is presented in continuous roll form.

2. A water resistive barrier (WRB) including furring strips as defined in claim 1 wherein said fasteners utilized to secure the WRB to the building structure are nails.

3. A water resistive barrier (WRB) including furring strips as defined in claim 1 wherein said fasteners are staples.

4. A furring strip for use in providing a space for drainage and drying when attached to the sheathing or the WRB which is in close contact with the sheathing wherein said furring strip is made of extruded closed cell polyethylene foam which inhibits water intrusion where construction fasteners are installed through said closed cell polyethylene foam furring strips.

5. A furring strip for use in securing WRB sheet material to a building structure wherein said furring strip is made of extruded closed cell polyethylene foam to provide self-sealing qualities to said furring strip when secured to said building by fasteners.

6. A furring strip for use in securing WRB sheet material as set forth in claim 5 wherein said fasteners are staples.

7. A furring strip for use in securing WRB sheet material as set forth in claim 5 wherein said fasteners are nails.

8. A furring strip for use in securing WRB sheet material as set forth in claim 5 wherein said furring strips limit the transfer of heat into a building structure by the fasteners securing the furring strips to said structure.

9. A closed cell polyethylene foam furring strip for use in providing a space for drainage and drying when attached to the sheathing of the WRB which is in close contact with the sheathing and inhibits water intrusion where construction fasteners are installed through said closed cell polyethylene foam furring strips wherein said furring strip is made of closed cell polyethylene foam material to minimize the heat transfer through the wall components.

10. A water resistive barrier (WRB) for use in frame construction wherein said WRB ensures drainage and drying of unwanted water between the main structure and exterior siding of a building;

said WRB comprising;

flexible water resistive barrier sheet material;

said furring strips fabricated from closed cell polyethylene foam material that sealingly engages any fasteners that are inserted therethrough; and all further wall components are attached to said building with additional fasteners that also penetrate said closed cell polyethylene furring strips which serve to provide a gasketing effect along said fastener.

11. A water resistive barrier (WRB) for use in frame construction as defined in claim 10 wherein said further wall component is siding.

12. A water resistive barrier (WRB) for use in frame construction as defined in claim 10 wherein said further wall components are building paper and metallic lath sequentially applied for a stucco or manufactured stone veneer residence.

13. A furring strip for use in securing WRB sheet material too a building structure wherein said furring strip is made of closed cell polyethylene foam material to minimize the heat transfer through wall components.

14. A furring strip of continuous extruded closed cell polyethylene foam produced in roll form wherein the roll has the advantage of allowing for longer lengths while maintaining compactness for shipping, storage and ease of handling;

said roll form also having the advantage of ease of installation wherein an installer merely grabs the free end of the roll and climbs to the highest part of the building where the furring strip is to be installed, and by gravity, release of the furring strip aligns itself vertically for easy attachment to the building structure by the installer providing for faster installation than is otherwise possible by aligning and installing shorter individual lengths of furring strip.