Protective drainage wraps

[0002] The present invention relates generally to protective wraps that are used to protect against air infiltration and moisture build-up in buildings. Specifically, the protective wraps of the present invention include cross-woven or cross-laminate materials.

[0003] There have been many different commercial protective wraps used in the construction of buildings, such as residential and commercial construction. Commercial protective wraps are used to protect against air infiltration and damaging moisture build-up. Air infiltration may occur in typical construction through, among other places, sheathing seams and cracks around windows and doors. Moisture build-up can occur externally in the wall cavity from, for example, leaking exterior finishes or coverings, and cracks around windows and doors. The exterior of the protective wraps should not trap the water, but rather allow it to flow downward so as to exit the wall system.

[0004] Commercial protective wraps are typically used as secondary weather barriers in buildings behind exterior finishes or coverings such as siding, brick, stone, masonry, stucco and concrete veneers. Stucco may be synthetic based (e.g., a polymer-based stucco) or cementitious (a mixture of Portland cement, lime and sand). One type of stucco system, exterior insulation finish system (drainage EIFS), that is used in buildings typically involves using a drainage plane, an insulation board, and a wire or synthetic mesh that accepts a cementitious coating. In stucco systems, protective wraps are not typically installed directly in contact with the cementitious coatings.

[0005] Both woven and non-woven commercial protective wraps are commonly used in the construction of buildings. The strength properties of woven wraps are typically much higher than the strength properties of non-woven wraps. Some woven wraps are translucent, which assist in locating studs, as well as window and door openings. Non-woven wraps, however, generally have higher permeabilities than woven wraps.

[0006] Commercial protective wraps, such as non-woven wraps, woven wraps and cross-laminated wraps, also may be micro-perforated so as to allow moisture vapor to pass therethrough. Most non-woven commercial protective wraps (such as spun bonded polyolefin wraps) are not perforated because the processes used in forming the wraps result in a structure that inherently allows the moisture vapor to pass through the wrap.

[0007] Accordingly, a need exists for a protective wrap that enhances drainage of damaging moisture build-up, while still protecting against air infiltration.

[0008] According to one embodiment, a protective drainage wrap comprises a first portion and a second portion. The first portion comprises cross-woven or cross-laminate material in the machine direction and in the transverse direction. The material in the machine direction comprises a polyolefin, polyester, nylon or combinations thereof and has a first thickness. The material in the transverse direction comprises a polyolefin, polyester, nylon or combinations thereof and has a second thickness. The second thickness is at least about 2 times greater than the first thickness so as to assist in providing drainage for moisture build-up. The second portion is a coating comprising a polyolefin, polyester, nylon or combinations thereof. The first and second portions are located adjacent to each other.

[0009] According to another embodiment, a protective drainage wrap comprises a first portion and a second portion. The first portion comprises cross-woven or cross-laminate material in the machine direction and in the transverse direction. The material in the machine direction comprises polyolefin, polyester, nylon or combinations thereof and has a first thickness. The material in the transverse direction comprises a polyolefin, polyester, nylon or combinations thereof and has a second thickness. The material in the transverse direction is yarn. The second thickness is at least about 2 times greater than the first thickness so as to assist in providing drainage for moisture build-up. The second portion is a coating comprising a polyolefin, polyester, nylon or combinations thereof The first and second portions are located adjacent to each other.

[0010] According to one method of using a protective wrap in a building, the protective wrap is provided. The protective wrap includes a first portion and a second portion. The first portion comprises cross-woven or cross-laminate material in the machine direction and in the transverse direction. The material in the machine direction comprises a polyolefin, polyester, nylon or combinations thereof and has a first thickness. The material in the transverse direction comprises a polyolefin, polyester, nylon or combinations thereof and has a second thickness. The second thickness is at least about 2 times greater than the first thickness so as to assist in providing drainage for moisture build-up. The second portion is a coating comprising a polyolefin, polyester, nylon or combinations thereof The first and second portions are located adjacent to each other. The protective wrap is installed over at least one of the framing members. Alternatively, the protective wrap is installed over sheathing.

[0011] According to one method of using a protective wrap in a building, the protective wrap is provided. The protective wrap comprises a solid sheet portion and a yarn portion. Alternatively, the protective wrap comprises a solid sheet portion and a plurality of tapes in the transverse direction. The solid sheet portion comprises polyolefin, polyester, nylon or combinations thereof The yarn portion comprises polyolefin, polyester, nylon or combinations thereof The yarn portion comprises a plurality of yarn strands being installed so as to assist in providing drainage for moisture build-up. The protective wrap is installed over at least one framing member.

[0012] FIG. 1 is a top perspective view of a cross-woven protective wrap according to one embodiment of the present invention;

[0013] FIG. 2 is a cross-sectional view taken generally along line 2—2 of FIG. 1;

[0014] FIG. 3 is a top perspective view of a cross-laminated protective wrap according to one embodiment of the present invention;

[0015] FIG. 4 is a cross-sectional view taken generally along line 4—4 of FIG. 3;

[0016] FIG. 5 is a cut-away perspective view of a protective wrap of FIG. 1 fastened to sheathing and a framing member according to one embodiment of the present invention;

[0017] FIG. 6 is a top perspective view of a yarn cross-woven protective wrap according to another embodiment of the present invention;

[0018] FIG. 7 is a cross-sectional view taken generally along line 7—7 of FIG. 6;

[0019] FIG. 8 is a cut-away perspective view of a protective wrap of FIG. 6 fastened to sheathing and a framing member according to another embodiment of the present invention;

[0020] FIG. 9 is a top perspective view of a yarn protective wrap according to yet another embodiment of the present invention; and

[0021] FIG. 10 is a cross-sectional view taken generally along line 10—10 of FIG. 9.

[0022] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that it is not intended to limit the invention to the particular forms disclosed but, on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

[0023] Turning now to the drawings and referring initially to FIGS. 1 and 2, a protective drainage wrap 10 according to one embodiment of the present invention is shown. The protective wraps of the present invention, including protective wrap 10, are adapted to be attached over sheathing or framing members. The protective wraps are typically covered by an exterior covering such as siding, brick, stone, masonry, stucco (e.g., synthetic or cementitious) or concrete veneer.

[0024] According to one embodiment of the invention, the protective wrap 10 of FIGS. 1 and 2 comprises a first portion 12 and a second portion or coating 14. The first portion 12 of the protective wrap 10 may be cross-woven such as shown in FIGS. 1 and 2. Alternatively, the first portion of the present invention may be cross-laminated, such as shown in FIGS. 3 and 4 with cross-laminated protective drainage wrap 20.

[0025] First Portion

[0026] The first portion of the protective wrap provides a desirable strength that assists in inhibiting or preventing tears and/or fraying that may be caused during installation. These tears and/or fraying may be caused by, inter alia, nails or staples during the installation of the protective wraps. These tears and/or fraying may also be caused after installation by environmental conditions such as the wind or by vandalism before the protective wrap is covered with an exterior covering.

[0027] The first portion 12, as shown in FIG. 1, comprises a plurality of machine direction (MD) tapes or strands 12aand a plurality of transverse direction (TD) tapes or strands 12b. The machine direction is also referred to as “warp”, while the transverse direction is also referred to as “fill” or “weft”. The first portion 12 of FIG. 1 is commonly referred to as a cross-woven scrim.

[0028] The scrim shown in FIG. 1 is a 10×4 count scrim (MD number per inch×TD number per inch) that has been enlarged. It is also contemplated that various other scrim counts may be used, including a 7×4 count, a 10×5 count and a 16×5 count, in forming the first portion 12 of the present invention. The scrim count is typically a greater number in the machine direction than the transverse direction. The MD scrim count is generally from about 6 to about 24 tapes per inch, while the TD scrim count is generally from about 3 to about 6 tapes per inch. The MD and TD scrim counts are generally lesser in number per inch as the respective widths of the MD and TD tapes are increased.

[0029] The plurality of machine direction tapes 12amay be made of materials such as polyolefins, polyesters, nylons or combinations thereof. Polyolefins that may be used in forming the machine direction tapes 12ainclude polypropylenes or polyethylenes. The term “polypropylene” as used herein includes polymers of propylene or polymerizing propylene with other aliphatic polyolefins, such as ethylene, 1-butene, 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 4-methyl-1-hexene, 5-methyl-1-hexene and mixtures thereof. Polypropylene not only includes homopolymers of propylene, but also propylene copolymers comprised of at least 50 mole percent of a propylene unit and a minor proportion of a monomer copolymerizable with propylene and blends of at least 50 percent by weight of the propylene homopolymer with another polymer.

[0030] The term “polyethylene” as used herein includes low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), metallocene-catalyzed linear low density polyethylene (mLLDPE) and combinations thereof.

[0031] An example of a “polyester” includes a polyester resin which is a polycondensation product of a dicarboxylic acid with a dihydroxy alcohol. An example of a “polyethylene terephthalate” includes a polyester resin made from ethylene glycol and terephthalic acid. An example of a “nylon” is a polyamide polymer that is characterized by the presence of the amide group (—CONH).

[0032] Each of the plurality of machine direction tapes 12amay be made of a single fiber or filament, or a plurality of fibers or filaments aligned with each other. The machine direction tapes 12amay also be referred to as cords. As shown in FIG. 1, the plurality of machine direction tapes 12aare substantially flat.

[0033] The plurality of transverse direction tapes 12bmay be made of materials such as polyolefins, polyesters, nylons or combinations thereof as described above with respect to the machine direction tapes 12a. Polyolefins that may be used in forming the transverse direction tapes 12binclude polypropylenes and polyethylenes. Each of the plurality of transverse direction tapes 12bmay be made of a single fiber or filament, or a plurality of fibers or filaments aligned with each other. The transverse direction tapes 12bmay also be referred to as cords. As best shown in FIG. 2, each of the transverse direction tapes 12bis shaped in a generally oval manner. The plurality of transverse direction tapes 12bare preferably substantially circular or circular in shape. The transverse direction tapes 12bare shaped in a manner that will allow water to flow down the channels formed between the transverse direction tapes 12bvia gravity.

[0034] If natural vapor transmission is desired in a woven protective wrap, the transverse direction tapes 12bmust be of a sufficient thickness to enable a natural vapor transmission to be formed when the coating 14 is applied to the first portion 12. The natural vapor transmission mechanism is formed via open interstices/spaces along the transverse direction tapes 12bafter the coating 14 is applied. A protective wrap with open interstices/spaces may not require physical perforations to meet typical building code requirements for water vapor transmission.

[0035] The protective wrap with open interstices/spaces may be perforated to enhance natural vapor transmission. If the protective wrap is formed without interstices/spaces, the protective wrap often is perforated to provide for desirable water vapor transmission. The size and shape of the perforations formed in the protective wrap may vary. If the perforations are substantially circular, the diameter of these perforations is generally from about 3 to about 15 mils. The spacing of the perforations formed in the protective wrap may also vary with respect to each other. One example of spacing that may be used between the perforations in the protective wrap is about {fraction (3/16)} of an inch.

[0036] Natural vapor transmission is often desirable because of moisture build-up occurring from internal moist air present in the wall cavity. Moisture build-up may occur from materials, such as green lumber, used in framing or structural sheathing. Moisture build-up may also occur from environmental elements, such as rain, during construction before an exterior finish has been installed or water that enters the installed wall system.

[0037] The thicknesses of transverse direction tapes 12bof the present invention provide unique vertical channels, when installed, that enhance moisture drainage external to the protective wrap (i.e., between the protective wrap and the exterior finish). The installed transverse direction tapes 12ballow water to readily exit a wall system. To enhance moisture drainage, the thickness of the transverse direction tapes 12bis generally at least about 2 times greater than the thickness of the machine direction tapes 12a. The thickness of the transverse direction tapes 12bis generally at least about 3 or about 4 times greater than the thickness of the machine direction tapes 12a. The thickness of the transverse direction tapes 12bmay be at from about 6 to about 8 times greater than the thickness of the machine direction tapes 12a.

[0038] The plurality of transverse direction tapes 12baccording to one embodiment of the present invention is shown in FIG. 5 after being installed. The transverse direction tapes 12bare generally perpendicular to the machine direction tapes 12aso as to enhance moisture drainage. It is contemplated that the tapes 12bmay be located generally diagonally with respect to the tapes 12aas long as the tapes 12bare in a generally downward position when installed.

[0039] The first portion 12 comprising a plurality of MD and TD tapes 12aand 12bmay be made from an extrusion process. After being formed, the tapes 12aand 12bmay be cross-woven by different processes. One contemplated process for weaving the tapes 12aand 12btogether is through the use of a loom.

[0040] Alternatively, the MD and TD tapes 12aand 12bmay be cross-laminated to each other by adhering the tapes 12aand 12btogether via the use of a suitable adhesive (see FIGS. 3 and 4). The adhesive is selected based on the materials used to form the tapes 12aand 12b.

[0041] Second Portion or Coating

[0042] The second portion or coating 14 of the protective wrap 10 is applied to the first portion 12. The coating 14 may be made from polyolefins, polyesters, nylons or combinations thereof as discussed above with respect to the first portion 12. Polyolefins that are typically used in forming the coating 14 include polypropylenes and polyethylenes. A coating 14 made from polypropylene is desirable because of the enhanced stiffness provided to the protective wrap.

[0043] The coating 14 of the present invention is generally applied to obtain a thickness of from about 0.5 mil to about 2.0 mils, and preferably from about 0.8 to about 1.2 mil. The coating is preferably applied in a sufficient thickness to the first portion 12 so that a natural vapor transmission is formed via interstices that allow the passage of water vapor.

[0044] The coating 14 is shown as being applied to one surface of the first portion 12 in FIG. 2. It is contemplated that the coating 14 may be provided on both surfaces of the first portion 12 (not shown) as long as the coating 14 enables the transverse direction tapes 12bto still provide channels that enhance moisture drainage, external to the protective wrap.

[0045] The coating 14 may be applied by various processes to the first portion 12. According to one process of the present invention, pellets of a resin(s) for forming the coating 14 are added in their solid form into an extrusion hopper. These pellets are heated to a sufficient temperature in an extruder to form a molten material. The molten material that will form the coating 14 exits the extruder through a die. The extruder typically has a horizontal die in which the molten material exits and falls vertically by gravity onto a surface of the first portion 12. At the same time the molten material is exited from the extruder, the first portion 12 proceeds in a direction transverse to the extruder.

[0046] The first portion 12 may proceed on a transport mechanism involving rollers that pull the cross-woven or cross-laminated material along a threaded path. The transport mechanism is located below the extruder die that extrudates the coating. The amount of coating 14 applied to the first portion 12 depends on factors such as the speed of the transport mechanism, size of the extruder die opening, and speed of the coating exiting the die. These variables should preferably be controlled to obtain a desired thickness of the coating so as to form interstices that allow for the passage of water vapor.

[0047] Yarn Portion

[0048] According to another embodiment of the present invention, a protective drainage wrap 60 is shown in FIGS. 6 and 7. As discussed above with respect to protective wrap 10, the protective wrap 60 is adapted to be attached to sheathing or framing members. The protective wrap 60 comprises a tape or strand portion 62, a yarn portion 64 and a coating portion 66. The tape portion 62 of FIGS. 6 and 7 comprises a plurality of tapes in the machine direction, while the yarn portion 64 comprises a plurality of yarn strands in the transverse direction.

[0049] The yarn portion 64 is capable of absorbing moisture such as water. Additionally, the yarn portion 64 may be capable of wicking the moisture which may provide further enhancement to the hydration properties. To assist in moving the water downwardly via gravity, the yarn portion 64 is preferably installed in a generally vertical position. In addition, the yarn portion 64 provides a channeling effect between the plurality of yarn strands to assist in moving the water downwardly. If the channel formed between adjacent yarn strands is blocked by, for example, stucco, then the water may be absorbed by the yarn. This absorbed water may flow downwardly via the yarn strand or may be transported to another channel for moving the water downwardly.

[0050] Types of yarn that may be used in the present invention include spun yarn, bulk continuous process (bcp) yarn and natural yarn (e.g., jute). Spun yarn may be formed by a two step process in which very small filaments are extruded and chopped to a selected length. These filaments are then spun into a continuous yarn using, for example, a spinning frame. Bulk continuous process yarns may be formed by extruding 70 or 80 very small fibers into continuous filaments that are spaced in close proximity to each other. The close proximity of the continuous filaments allows for the filaments to be intertwined by air entanglement or twisting to create a single yarn.

[0051] The yarn portion 64 may be made of polymeric materials such as polyolefins, polyesters, nylons or combinations thereof Some contemplated polyolefins to be used in forming the yarn portion 64 include polypropylenes or polyethylenes. Each of the plurality of strands of the yarn portion 64 shown in FIG. 6 is made of a plurality of fibers or filaments twisted with each other. One type of yarn that is contemplated is a spun polypropylene yarn that is manufactured by BP Amoco Fabrics. The tape portion 62 and the yarn portion 64 may be both made from polypropylenes.

[0052] The tape portion 62 may be made of materials such as polyolefins, polyesters, nylons or combinations thereof Examples of such materials are described above with respect to the first portion 12 including polypropylenes or polyethylenes. The tape portion 62 may be made in a similar manner as described above with respect to the machine direction tape 12a.

[0053] The yarn portion 64 and the tape portion 62 are preferably located in directions that are generally perpendicular to each other. This location of the yarn portion 64 with respect to the tape portion 62 is depicted in FIG. 6. It is contemplated, however, that the yarn portion 64 may be located generally diagonally from the tape portion 62 as long as the yarn portion 64 is in a generally downward position when installed.

[0054] As depicted in FIG. 6, each of the plurality of yarn strands of the yarn portion 64 is woven between the plurality of tapes/strands of the tape portion 62. When cross-woven, the combination of the yarn portion 64 and the tape portion 62 may be referred to as a cross-woven scrim. The yarn portion 64 and the tape portion 62 may be woven by various techniques. One such example is with the use of a loom that weaves the yarn portion 64 and the tape portion 62.

[0055] Alternatively, the tape portion 62 and the yarn portion 64 may be cross-laminated (not shown) by adhering the plurality of tapes and plurality of yarn strands together via the use of a suitable adhesive.

[0056] The coating 66 may be made from polyolefins, polyesters, nylons and combinations thereof as discussed above with respect to the coating 14. Polyolefins that are typically used in forming the coating 66 include polypropylenes and polyethylenes. A coating 66 made from polypropylene is desirable because of the enhanced stiffness provided to the protective wrap. The thickness of the coating 66 is similar to that described above with respect to the coating 14. The coating 66 may be applied to the tape portion 62 and the yarn portion 64 by the same processes as described above with respect to coating 14.

[0057] Referring to FIGS. 9 and 10, a protective drainage wrap 90 comprises a solid sheet portion 92 and a yarn portion 94 according to yet another embodiment of the present invention. The protective wrap 90, as discussed above with respect to protective wraps 10, 20 and 60, is adapted to be attached over sheathing or framing members.

[0058] To assist in draining the moisture via gravity, the yarn portion 94 is preferably installed in a generally vertical position (i.e., the transverse direction material). The yarn portion 94 is similar to that described above with respect to yarn portion 64. The protective wrap 90 may include perforations therein to assist in increasing the water vapor transmission rate.

[0059] The solid sheet portion 92 may be made of polymeric materials such as polyolefins, polyesters, nylons or combinations thereof The solid sheet portion 94 may be a breathable film. Similarly, the yarn portion 94 may be made of polymeric materials such as polyolefins, polyesters, nylons or combinations thereof Alternatively, the yarn portion may be cross-woven through a solid sheet tape portion having a plurality of holes therein (not shown).

[0060] The protective drainage wrap may comprise a solid sheet portion and a plurality of transverse direction tapes, such as the transverse direction tapes 12bdescribed above. The plurality of tapes are installed so as to assist in providing drainage for moisture build-up.

[0061] Protective Wrap Additives

[0062] Additives to the protective wraps are contemplated in the present invention. For example, the protective wraps may include colorant additives to resist the glare of the sun. The addition of colorant assists workers in installing the protective wrap. The protective wraps may also include chemical additives such as ultraviolet inhibitors and antioxidants to withstand deterioration from prolonged exposure to sunlight. In addition, the protective wraps of the present invention may be translucent. Translucent protective wraps assist in locating studs, as well as window and door openings. The protective wraps of the present invention may also include printing thereon.

[0063] Properties of the Protective Wrap

[0064] The protective wraps of the present invention provide improved drainage characteristics. The protective wraps of the present invention also provide for water vapor transmission rates (WVTR) as measured by ASTM E 96 Procedure A. The woven protective wraps generally have water vapor transmission rates of from about 5 to about 15 perms.

[0065] The tensile strength of woven protective wraps as measured by ASTM D 882 is generally greater than about 25 lbs./in. The tensile strength of woven protective wraps is preferably greater than about 30 lbs./in. and more preferably greater than about 35 lbs./in. as measured by ASTM D 882. It is beneficial that the protective wraps of the present invention are strong so as to inhibit or prevent tearing and/or fraying during or after installation. Tearing and/or fraying may, and typically will, result in unwanted air infiltration and/or moisture penetration.

[0066] The TD tear strength of woven protective wraps as measured by ASTM D 1117 is generally greater than 25 lbs. The TD tear strength of woven protective wraps is preferably greater than about 30 lbs. and more preferably greater than about 35 lbs. as measured by ASTM D 1117.

[0067] Non-woven protective wraps, such as breathable films, generally have water vapor transmission rates of up to from about 30 or 60 perms as measured by ASTM E 96, Procedure A. The tensile strength of non-woven protective wraps as measured by ASTM D 882 is generally greater than about 15 lbs./in, and preferably greater than about 20 or 25 lbs./in. The TD tear strength of non-woven protective wraps as measured by ASTM D 1117 is generally greater than 10 lbs., and preferably greater than about 15 or 20 lbs.

[0068] The protective wraps of the present invention may be formed into a number of shapes. The protective wraps, however, are generally stored in a roll on a circular cardboard core. The protective wraps of the present invention may be manufactured in a variety of sizes. Popular sizes used in residential and commercial construction include, but are not limited to, 3 foot by 100 foot (3′×100′), 4.5′×100′, 4.5′×150′, 4.5′×195′, 9′×100′, 9′×150′, 9′×195′ and 10′×150′. For example, the 3′ length extends in the transverse direction, while the 100′ length extends in the machine direction.

[0069] The thickness of the protective wraps may also vary, but is generally from about 8 to about 12 mils as measured by ASTM D 751. The thickness of the protective wraps is typically from about 9 to about 11 mils. Popular thickness of protective wraps includes about 10 mils.

[0070] Use of the Protective Wrap

[0071] The protective wraps of the present invention may be used as wraps in residential and commercial buildings. The protective wrap is typically covered by an exterior covering like siding, brick, stone, masonry or concrete veneer. Alternatively, the protective wraps of the present invention may be used as stucco drainage wraps in which the protective wraps are covered by a cementitious exterior covering (stucco or EIFS). The protective wrap may also assist in controlling the drying/curing process of the cementitious exterior covering so that the hydration of the exterior covering will not occur too fast or too slow.

[0072] Methods of Applying the Protective Drainage Wrap

[0073] According to one process of the present invention, a protective drainage wrap is attached directly to sheathing which is attached to framing members. The sheathing may be made from various materials. Some examples of materials used as sheathing include thin composite laminations, fiberboard, oriented-strand board (OSB), plywood, polyisocyanurate foam, extruded polystyrene (XPS) foam and molded expanded polystyrene (EPS) foam. Some examples of framing members include plywood and OSB. The protective wraps may be attached mechanically to the sheathing by using fasteners such as nails or staples.

[0074] One example of a protective wrap attached to a sheathing is shown in FIG. 5 where the protective wrap 10 (first portion 12 and second portion 14) is installed over the sheathing 30. The sheathing 30 is attached to a plurality of framing members 35. Types of framing members that may be used include southern yellow pine (SYP) and spruce pine fur (SPF). Some framing members, however, may be made of metal. The protective wrap 10 of FIG. 5 has been cut-away to depict the first portion 12 and the coating 14. FIG. 5 also shows an exterior covering (siding 40) that is located on an exterior surface of the protective wrap 10. The first portion 12 is located adjacent to the siding 40 so as to assist in allowing water to exit a wall system.

[0075] Similarly, the protective drainage wrap 60 (tape portion 62 and yarn portion 64) is shown in FIG. 8 over sheathing 70. The sheathing is attached to a plurality of framing members 75. The protective wrap 60 of FIG. 8 has been cut-away to depict the tape portion 62, the yarn portion 64 and the coating 66. FIG. 8 also shows an exterior covering (siding 80) that is located on an exterior surface of the protective wrap 60. The yarn portion 64 is located adjacent to the siding 80 so as to assist in allowing water to exit a wall system.

[0076] The sheathing 20 (FIGS. 3 and 4) and sheathing 90 (FIGS. 9 and 10) may be attached in a similar fashion as described above with respect to protective drainage wraps 10 and 60.

[0077] According to another process of the present invention (not shown), the protective wrap is installed directly over a plurality of framing members. The protective wrap may be attached to the plurality of framing members in a similar manner as discussed above with respect to attaching the protective wrap to the sheathing.

[0078] The following examples are presented to demonstrate various aspects of protective wraps. All of the protective wraps (Wraps 1-6) were tested for water vapor transmission rate (WVTR) in accordance with ASTM E 96. The water vapor transmission rate was reported in perms [(grains/ft²) (h) (in. Hg)].

[0079] Tested Wraps 1-6

[0080] Wraps 1-6 were also tested for drainage time both quantitatively and qualitatively. Wraps 1-6 during the drainage testing were visually inspected to determine drainage performance and characteristics.

[0081] Inventive Wrap 1 comprised a cross-woven material in the machine and transverse directions. The machine direction material was made of a polypropylene rectangular tape, while the transverse direction material was made of a generally circular polypropylene filament. The thickness of the transverse direction filament was about 0.020 inches (20 mils). The thickness of the uncoated machine direction tape was 1.9 mil, while the thickness of the coated machine direction tape was 18 mils. The cross-woven material of Inventive Wrap 1 had a scrim count of 10×4 (machine direction×transverse direction). Inventive Wrap 1 included a coating made of a polypropylene/polyethylene blend that was applied to the cross-woven material, resulting in interstices. Inventive Wrap 1 did not have any machine-made perforations.

[0082] Inventive Wraps 2 and 3 comprised a cross-woven material in the machine and transverse direction. The machine direction material of Inventive Wraps 2 and 3 was made of a polypropylene rectangular tape, as described above with respect to Inventive Wrap 1. The transverse direction material was made of spun polypropylene yarn filaments. The spun yarn filaments were manufactured by BP Amoco Fabrics. The thicknesses of the transverse direction yarn filaments in Wraps 2 and 3 were about 22 mils, while the thicknesses of uncoated machine direction tapes were 1.9 mil. Both Inventive Wraps 2 and 3 had a scrim count of 10×5.

[0083] Inventive Wraps 2 and 3 included coatings made of a respective polypropylene/polyethylene blend that was applied to the cross-woven material, resulting in interstices. Inventive Wraps 2 and 3 did not have any machine-made perforations. Inventive Wraps 2 and 3 had different WVTR values because of the amount of coating applied to the cross-woven material. The coated machine direction tape of Wrap 2 was 8 mils thick, while the coated machine direction tape of Wrap 3 was 10 mils thick. The heavier coating of Inventive Wrap 3 did not bridge the gaps of the cross-woven material as well as the lighter coating of Inventive Wrap 2. Thus, Inventive Wrap 3 had larger interstices and consequently a higher WVTR value.

[0084] Comparative Wrap 4 was a 10×5 cross-woven housewrap marketed under the name PINKWRAP® by Owens Corning. Comparative Wrap 4 had identical polypropylene rectangular tapes that formed the transverse and machine direction material of the cross-woven housewrap. The cross-woven housewrap was coated with a polypropylene/polyethylene blend, resulting in interstices. Comparative Wrap 4 did have machine-made perforations.

[0085] Comparative Wrap 5 was a two-layer building paper made by FORTIFIBER® under the tradename JUMBO TEX®. Comparative Wrap 5 was a two-layered asphalt-saturated kraft building paper. Comparative Wrap 5 did not have any machine-made perforations.

[0086] Comparative Wrap 6 was a non-woven housewrap made by DuPont under the tradename TYVEK® HOMEWRAP®. Comparative Wrap 6 was a non-woven, spun-bonded polyolefin, breathable structure that included microscopic pores. Comparative Wrap 6 did not have any machine-made perforations.

[0087] Testing Preparation/Method

[0088] The testing preparation and method employed is a modified version of a test method that was developed by the National Research Council of Canada. The difference between the testing below and that employed by the National Research Council of Canada include (a) replacing stucco and the plywood sheathing with plexiglas panels (for visual inspection) and (b) using a modified sealant to inhibit or prevent leakage at the sample edges.

[0089] The testing assembly included two ½ inch thick plexiglas panels to sandwich the building paper or drainage wrap. Plexiglas was used to visually observe and evaluate the actual drainage of water. The building paper or drainage wrap was secured between the two plexiglas panels using screws with washers and a gasket material. The back plexiglas panel measured about 12 inches by 24 inches (12″×24″) and the front plexiglas panel measured about 12″×18″.

[0090] The edges of the assembly were sealed with white acrylic latex caulk and then covered with an additional layer of wax (50% beeswax/50% paraffin wax). The layer of wax was brushed on over the dried caulk to inhibit or prevent potential water leakage at the edges. A bead of caulk was then placed around the top edge of the front plexiglas panel to accept an inflow container holding water. The inflow container was a rectangular plexiglas box with no lid and measured 11¾″ in length, 3½″ in width, and 4¾″ in depth. The back side (bottom edge) of the container had a row of 25 holes, each measuring {fraction (1/16)}″ in diameter. The inflow container was mounted on the top edge of the front plexiglas panel with the holes adjacent to the building paper or drainage wrap. All edges between the inflow container and the plexiglas panels were sealed with the caulk and wax.

[0091] The testing assembly was mounted on a rack to hang vertically over a drainage pan, which was used to capture water draining from the bottom edge of the assembly. A liter of tap water at room temperature included blue food coloring to improve the visual observation. The liter of water was poured into the inflow container and a stopwatch was set to record the amount of time required for each assembly to drain the water.

[0092] The results of the testing are shown in the Table below.

[0093] As shown in the Table, Inventive Wraps 1-3 had far superior drainage times as compared to Comparative Wraps 4-6 (Compare about 3-6 minutes vs. over 2 hours).

[0094] Inventive Wraps 1-3 also had an even flow pattern during the drainage of the water. Comparative Wrap 4 had an even flow pattern, but Comparative Wraps 5 and 6 had an uneven flow pattern. Inventive Wraps 1 and Comparative Wraps 4-6 had drainage on only the front side. Inventive Wrap 2 had preliminary drainage on the front side with some later leakage on the back side. Inventive Wrap 3 had immediate drainage on the front and back sides. It is preferred to have flow on the front side only. The flow of water on the front side is controlled by the number and size of the interstices/perforations and the ease of the flow of water.

[0095] While the present invention has been described with reference to one or more particular embodiments, those skilled in the art will recognize that many changes may be made thereto without departing from the spirit and scope of the present invention. Each of these embodiments and obvious variations thereof is contemplated as falling within the spirit and scope of the claimed invention, which is set forth in the following claims.