Patent Publication Number: US-6991535-B2

Title: Externally baffled ridge vent and methods of manufacture and use

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application is a continuation-in-part of U.S. patent application Ser. No. 10/610,067 to Dustin Ciepliski and Jeff Hansen, entitled “Externally Baffled Ridge Vent and Methods of Manufacture and Use” filed Jun. 30, 2003, now U.S. Pat. No. 6,881,144, the entirety of which is hereby incorporated by reference herein. 

   FIELD OF THE INVENTION 
   The present invention is related generally to ridge vents for covering the opening of the roof ridge, and more particularly to rollable, baffle and ridge vent assemblies. 
   BACKGROUND OF THE INVENTION 
   In the winter, household activities, such as cooking, showering and doing the laundry, generate moisture that can damage the attic insulation and building materials of the roof. In the summer, attic temperatures can rise to over 150° F., which can cause premature aging and cracking of wood and roofing materials. These elevated temperatures can also increase cooling costs for the home owner. In the construction of rooves, therefore, it is often desirable to provide a ventilation opening at the roof ridge and cover it with a vent. Ridge vents are passive ventilation systems which provide openings through which air can convectively flow to and from under the roof structure to provide ventilation. 
   Ridge vents typically cover any elongated opening, such as one that is formed in a roof and that extends along the peak of the roof, with the opening typically being in the range of about 10–20 cm in width and running along a substantial portion of the roof peak. Typical ridge vents include “shingle-over roof ridge vents” and exposed roof vents. See for example U.S. Pat. Nos. 6,361,434; 6,233,887; 6,450,882; 6,260,315 and published U.S. application 2002/0100232A1, all of which are incorporated herein by reference. 
   Many ridge vents have been developed that are made of polymeric materials that are flexible along a longitudinal axis in order to permit the ridge vent to conform to the sloped sides of a roof to cover the ridge opening. These ridge vents typically include a plurality of vents and supporting structures that depend from a common panel and that serve both the functions of resisting entry of precipitation, insects, and foreign manner, while providing supportive structures that lift the panel away from the roof and provide crush resistance. It is further desirable that ridge vents have means to create a “Venturi effect” or air draft to draw hot air outwardly from the underlying attic. 
   Prior art roof ridge vents are known that can be rolled for compact packaging and transport to an installation site. However, to make these ridge vents rollable requires some sacrificing of thermal efficiency in drawing hot air from the underlying attic, or costly modifications to the baffle structure in order to allow the ridge vent to be rolled in a spiral form. See U.S. Pat. No. 6,233,887 col. lines 50–61 and col. to lines 45–55. 
   Accordingly, there remains a need for a ridge vent, and particularly a rollable roof ridge vent which can be made cost-effectively, and which efficiently assists convection of heat and moisture from beneath a roof. 
   SUMMARY OF THE INVENTION 
   Ridge vents and methods of their use are provided. In a first embodiment, the preferred ridge vent includes an elongated flexible member having a central panel portion, a pair of lateral edges and a pair of transverse ends. A pair of vent openings are disposed proximate to the lateral edges. The central panel portion includes a plurality of support ribs for supporting the central panel portion above the roof. A pair of baffles is disposed laterally from the vent openings and the lateral edges. Each of the baffles is oriented in a first direction relative to the central panel portion for at least a period of time prior to installation and is oriented in a second direction relative to the central panel portion after the installation. 
   In a preferred embodiments, the roof ridge vent can be molded such that the baffles become generally parallel with (e.g., ±30°) the central panel when rolled. The baffle are then orientated in a more vertical position with respect to the central panel portion during installation, either manually or naturally by the shape or design of the baffle itself. 
   In one embodiment, the baffles are pivotally coupled to the lateral edges of the central panel portion. The baffles can be locked in vertical orientation by the use of clips or other securing means. The baffles can also be vertically oriented externally by imposing stresses, or reinforcing ribs, for example, in the right locations during the molding or fabrication of the ridge vent. In this manner, the baffles can be oriented in a flattened position when the vent is rolled, and then they can spring back once the vent is unrolled. These stresses, and/or reinforced portions of the vent, can help insure that the baffle is always naturally in a vertical orientation once installed, thereby reducing instances of improper installation. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompany drawings illustrate preferred embodiments of the invention as well as other information pertinent to the disclosure, in which: 
       FIG. 1  is a front perspective view of a rolled ridge vent of the present invention; 
       FIG. 2  is a top perspective view of the preferred ridge vent, in which the top of the central panel portion has been cut away; 
       FIG. 3  is an enlarged view of the louver and baffle portion of the ridge vent of  FIG. 2 , showing a preferred clip for creating a fixed distance between the baffle and the louvers; 
       FIG. 4  is a cross-sectional side plan view, taken through line  4 — 4 , of the ridge vent section of  FIG. 2 , without the cutout; 
       FIG. 5  is a side-plan view of the ridge vent cross-section of  FIG. 4 , showing the baffles disposed in their final position; 
       FIG. 6  is a side plan, cross-sectional view of an additional ridge vent of this invention employing a different baffle construction; 
       FIG. 7  is a side perspective, partial and cross-sectional view of the additional baffle support of  FIG. 6  for use in disposing the baffle in an upright position; 
       FIG. 8  is a front perspective partial view of a roof ridge employing the roof vent of  FIG. 7  and a shingle—over vent construction; 
       FIG. 9  is a front perspective phantom drawing of an index molding connection between two ridge vent sections; 
       FIG. 10  is a front perspective phantom drawing of the ridge vent sections of  FIG. 9  being melt bonded together; 
       FIG. 11  is a top perspective view an alternative embodiment of a rollable ridge vent (shown partially rolled) employing an alternative baffle construction; 
       FIG. 11A  is a bottom perspective view of the rollable ridge vent of  FIG. 11A ; 
       FIGS. 12 and 13  are top perspective views of the ridge vent of  FIG. 11A  showing the baffle in alternative orientations; 
       FIGS. 11B ,  12 A, and  13 A are enlarged, partial side plan views of the rollable ridge vent of  FIG. 11  showing a baffle in various orientations; 
       FIG. 14  is a front perspective phantom drawings of an index molding connection between two ridge vents; and 
       FIG. 14A  is a front perspective phantom drawings of the ridge vent sections of  FIG. 14  being melt bonded together; 
       FIGS. 15 and 15A  illustrate alternative embodiments of the index molding connection and melt bond connection, respectively, of  FIGS. 14 and 14   a;    
       FIG. 16  is an enlarged, partial side plan view of a ridge vent showing an alternative embodiment of a baffle; 
       FIG. 17  is an enlarged, partial side plan view of a ridge vent showing another alternative embodiment of a baffle; 
       FIG. 18  is an enlarged, partial cross-sectional view showing a roof installation including the ridge vent of  FIG. 17 ; 
       FIG. 19  is a enlarged, partial bottom plan view of an embodiment of a rollable ridge vent with a clip for securing the baffle in a desired position; and 
       FIG. 20  is a partial, enlarged bottom perspective view of another alternative embodiment of a rollable ridge vent. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   This invention provides ridge vents which can be used in shingle-over roof vent applications, roll-out shingle over roof ridge vent applications, and in the applications where shingles are not employed over the vent. In addition, methods of installing these ridge vents, and methods of manufacturing them are provided. The roof vents of this invention can be designed for ridge and hip roof applications, they can have a low profile for a minimum accented ridge line. The vent opening or louver openings are preferably designed to keep out insects and weather infiltration, and the external baffles are desirably structured to deflect wind and rain and create negative air pressure (“Venturi effect”). The air vents of this invention create a balanced system of intake and exhaust through the attic for provided greater airflow than conventional roof vents or turbine vents. The preferred external baffles are desirably molded into the roof vent in such a way that they can be readily rolled into a coil, laid out over an opening in a roof vent, and positioned in their final form easily, and without significant additional cost to the installer. 
   With respect to the drawings, and in particular,  FIGS. 1–5  thereof, a ridge vent  101  is provided for covering an opening of a roof ridge. The ridge vent  101  is preferably rollable into a spiral coil  100 , but can be equally provided in a fixed or more rigid form. 
   The ridge vent  101  includes an elongated flexible member having a central panel portion  11 , a pair of longitudinal side portions and a pair of transverse ends. The central panel portion  11  includes a plurality of support ribs  18  for supporting the central panel portion  11  above a roof. Each of the side portions contains a plurality of channels, e.g., formed by the support ribs  18 , for directing air current, a vent opening, and a baffle  14  disposed laterally from the vent opening. The baffles  14  are originally disposed in a first direction, for example in a relatively flat position, or substantially parallel (±30°) with the proximate central panel portion  11  or roof, for at least a period of time prior to insulation, and are then oriented in a second direction, which is generally perpendicular to (±30°) or upright in relation to the roof or proximate central panel portion  11 . 
   The ridge vent  101  embodiment of this invention is preferably constructed from a polymer material, such as polypropylene, polyvinylchloride, or polyethylene, and more preferably from high impact copolymer polypropylene. The ridge vent  101  laid over, or roll  100  can be unrolled over an opening in a roof ridge. The central panel portion  11  preferably includes a plurality of support ribs  18  which in the most preferred embodiment are about 1/16″ in thickness and about 2–4″ in length. Preferably, the ribs alternate in 2″ or 4″ lengths as shown in  FIG. 2  forming channels there between. The support ribs  18  preferably terminate laterally in a sloping surface, coextensive with a vent opening. The vent opening is preferably protected by a series of louvers  10 , but a screen or partially obstructed opening of any kind will do. The louvers  10  and channel desirably direct air current from under the roof and from the outside to the attic. The louvers  10  are preferably inclined at about 45° from the central panel  11 . Extending from the bottom of the longitudinal side portions of the elongated flexible member are baffles  14 , which are preferably integrally molded with the ridge vent  101 , but can be separately attached to the ridge vent, such as by, adhesive, melting bonding or ultrasonic welding. The slots in the vent opening are preferably between 1/16–1¼″ in width, and are designed to keep out insects and weather infiltration, such as snow, rain and hail. 
   The external baffles  14  are most desirably integrally formed with the ridge vent  101 , and form a portion of the longitudinal side portions of the ridge vent  101 . They are designed to deflect wind and rain and create negative air pressure, or a Venturi effect to draw hot air outwardly from within the underlying attic. In most rollable ridge vents, the baffle is a separate item which is inserted under the ridge vent during installation. In U.S. Pat. No. 6,361,434, a rollable baffle and ridge vent combination is disclosed. The ridge vent of the &#39;434 patent includes a fixed baffle having a plurality of deformed triangles to permit it to collapse in accordion fashion upon itself during rolling. A similar undulated sidewall in the baffle to permit the vent to be rolled without significant distortion is disclosed in Smith, U.S. Pat. No. 6,260,315. In the preferred embodiment  101  of the present invention, the baffle is preferably manufactured with the vent in a one piece construction with the baffle oriented in a first direction, followed by maneuvering the baffle  14 , either manually or naturally, into a second operable direction during the installation of the ridge vent on a roof ridge opening. This permits the roof vent to be rolled much more easily, and permits more cost-efficient manufacturing methods, such as index injection molding. 
   With respect to the details of  FIG. 2–5 , the preferred ridge vent  101  further includes an internal gusset  16  for connecting selective supporting ribs  18  in the central panel portion  11  of the ridge vent  101 . A plurality internal gussets  16  are desirably molded or manufactured at the same time as the remaining portions of the ridge vent  101 , and can contain the same polymer composition, a different or more rigid polymer composition, or a metallic insert for example. As shown in the enlarged view of  FIG. 3 , the baffles  14  can include optional louver spacer clips  12  which can clip between louvers  10 , or rest on a surface of a louver  10 , or some other vent surface, to provide a predesignated spacing between the baffles  14  and the louvers  10  to create the desired negative air pressure or Venturi effect. In the ridge vent embodiment  101  of  FIGS. 4 and 5 , the baffles are oriented in a generally flat position with their louver spacer clips  12  being substantially perpendicular to the central portion  11 . The baffles  14  at this time, are generally parallel with the surface of the central portion  11  or the roof, if installation is imminent. Following the unrolling of the ridge vent roll  100  into a position on a ridge opening, the baffles  14  are moved from a first orientation to a second orientation, which is generally perpendicular to the nearest or proximate central portion  11  and, which is also generally perpendicular to the roof, as shown in  FIG. 8 . The louver spacer clips  12  can be intermittently disposed along the baffle  14 , in a preferred spacing of about 12″. The clips  12  can be integrally formed in the vent mold, or separately attached as described herein connection with the baffles  14 . 
   An alternative baffle design of ridge vent  201  is shown in  FIGS. 6–8 . The alternative baffle  20  is also preferably oriented in a first direction prior to use, and in a second direction, after it is installed, such as disclosed in  FIGS. 6 and 7 . The alternative baffle  20  includes a louver spacer portion  22  and a baffle support  24 . As shown in  FIG. 7 , the louver spacer portion  22  aligns with the generally 45° surface of the louvers  10 , while the baffle support  24  forms a base with the roof surface, and is generally parallel thereto, as shown in  FIGS. 7 and 8 . The louver spacer portion  22  and baffle supports  24  are preferably integral with the baffle  20  and are also spaced about 12″ apart along the baffle  20 . 
   The ridge vents  101  of this invention are relatively easy to install in shingle over ridge vent or standard applications. In the preferred embodiment, the ridge vent  101  is unrolled and disposed over an opening of a roof ridge. The baffles  14  are flexed, or otherwise reoriented, from a first direction to a second direction relative to the central panel portion  11 , the roof, or both, as shown in  FIGS. 4–8 . Preferably the orientation step includes applying a support means for assisting the baffles to achieve the second position. In the preferred embodiments of this invention, the support means may be manual support means, such as clips, fasteners or stand-offs, or natural support means, such as employing ribs or areas of stress in the flexible member or ridge vent so that the baffles orient themselves while being applied to a roof ridge. Preferably laying the ridge vent  201  on a roof, causes contact between the baffle supports  24 , which forces, or bends, baffles  20  into a position which is more vertical. Alternatively, a combination of manual and natural support means can be employed. 
   In the shingle-over ridge vent installation methods of this invention, a plurality of shingles can be disposed over a portion of the ridge vent  201  and both the ridge vent and the shingles can be simultaneously nailed to a roof substrate, such as plywood, studs, tongue and groove planks, or the like, to secure both the roof vent  201  and shingles in place. In the installation shown in  FIG. 8 , the shingles are layered over the fasteners of the adjacent shingle, such as to minimize exposure to water leakage. The shingles are preferably layered so as to leave the vent opening, or louvers  110 , open. They should also not interfere with the Venturi action caused by the baffles  20 . The ridge vent  201  can further include a foam insert (not shown), which can seal the end of the vent prior to completion of the installation. 
   This invention also contemplates a more efficient manufacturing process for making ridge vents, a shown in  FIGS. 9 and 10 . The preferred method includes a forming operation employing polymeric materials. The forming operation can include injection molding, extrusion or compression molding, for example. In a preferred embodiment, the ridge vent is made by index injection molding. In such a preferred embodiment, a mold  102  having upper and lower mold sections, shown in phantom in  FIG. 9  is provided for forming a mold cavity. A quantity of polymeric material is disposed in the mold cavity and a first ridge vent section  101 , also shown in phantom is formed in the mold cavity. Next, the first ridge vent section  101  is indexed so that it is substantially moved beyond the mold cavity but remains in contact with the mold  102 . As shown in  FIG. 10 , a small stepped extension formed in the baffle  14  and central panel  11 , can remain in the mold  102 . Finally, a second quantity of polymer is disposed between the mold sections of mold  102  and a second ridge vent section is formed which is connected to the first ridge vent section  101 . The cooled first ridge vent section can then be rolled up in lengths containing about 20–50 feet of vent material, which is then packaged in a paper or polyethylene wrap. 
     FIGS. 11 and 11A  are top and bottom perspective views, respectively, of an alternative embodiment of a rollable ridge vent  201 . Like ridge vent  101 , rollable ridge vent  201  includes an elongated flexible member having a central panel portion  202 , a pair of lateral edges  204  and a pair of transverse ends. In one embodiment, the central panel portion is generally planar when unrolled between the lateral edges  204 . A pair of vent openings  210 , preferably slotted vent openings, are disposed laterally inwardly from the lateral edges  214 . In a preferred embodiment, the vent openings are formed in and through the central panel portions  202 , as shown, and proximate to lateral edges  204 . The slots in the vent opening are preferably between 1/16–1¼″ in width, and are designed to keep out insects and weather infiltration, such as snow, rain and hail. As shown in  FIG. 11A , the central panel portion  202  also includes a plurality of support ribs  218  for supporting the central panel portion  202  above the roof. The central panel portion  202  can also include a plurality of spaced gussets  216  distributed on the bottom surface thereof 
   A baffle  214  is pivotally connected to each lateral edge  204 . As shown in  FIGS. 11 and 11A  and the enlarged, partial side plan view of  FIG. 11B , the baffles  214  are generally oriented in a first direction substantially parallel (±30°) to the proximate, top major surface of the central panel portion  202  prior to installation, such as when the ridge vent  201  is rolled or being rolled. Although rollable ridge vent  201  of  FIGS. 11 and 11A  is shown in a partially rolled state, this is for illustrative purposes only. As described below, baffles  214  are preferably not oriented in the same plane with the central panel portion once the ridge vent is unrolled, but rather are oriented in a more vertical orientation to the central panel portion when the ridge vent is unrolled.  FIGS. 11 and 11A  illustrate the orientation that the baffles  214  naturally take as the ridge vent is flexed during rolling and when the ridge vent is completely rolled, with the top major surface of central panel portion  202  being rolled on itself, i.e., with the support ribs  218  and gussets  216  on the outside of the roll like the embodiment shown in  FIG. 1 . 
     FIGS. 12 ,  12 A and  FIGS. 13 ,  13 A illustrate embodiments of the rollable ridge vent  201  once unrolled. More specifically, these figures illustrate the baffles  214  being oriented in a second direction for installation once the ridge vent  201  is unrolled.  FIGS. 13 and 13A  illustrate the baffles  214  being substantially perpendicular, i.e., at an angle of or about 90° (e.g., 80–100°), to the central panel portion  202 . It is preferred that the ridge vent is molded in such a way so that the ridge vent has a natural tendency to orient itself in the direction shown in  FIGS. 13 and 13A  once unrolled. However, it is believed that depending on, for example, how long the ridge vent remains rolled (such as during storage thereof) and the polymer used, the baffles may self orient in a direction short of perpendicular, such as shown in  FIGS. 12 and 12A , due to, for example, polymer memory. In any event, this second direction is preferably between about 30–120° relative to the plane of top central panel portion when flat and before it is applied to a roof&#39;s apex, and more preferably 45–90° relative to the central panel portion, and still more preferably 75–90° relative to the central panel portion. 
   Regardless of the orientation direction of the baffles  214  once the rolled ridge vent is unrolled, because the baffles  214  are pivotally connected to the lateral edges  204  of the central panel portion  20 , they can be pivoted into a desired more vertical second direction relative to the flat central panel portion for installation. If this preferred installation second direction is not the natural orientation that the baffles take once the ridge vent  201  is unrolled, or if more rigidity is desired, clips or other fasteners, such as described above in the embodiment of  FIGS. 3–5 , may be provided to lock the baffles  214  into a desired orientation when installed, such as the perpendicular orientation shown in  FIGS. 13 and 13A . Alternatively, an adhesive strip, for example, a two sided pressure sensitive adhesive tape having a release paper strip, can be applied in the gap  213  shown in  FIG. 12A . In the field, the release paper can be removed and the tape can secure the baffle  214  to the corner  204  in the position shown in  FIG. 13A . 
   In one embodiment, spaced clips or fasteners  220  can be disposed to clip onto an adjacent support rib  218  to secure the baffles  214  in the desired position. This embodiment is shown in the enlarged, partial bottom plan view of  FIG. 19 . 
     FIGS. 16 and 17  are partial, enlarged side plan views illustrating alternative embodiments of rollable ridge vents. In the embodiment of  FIG. 16 , baffle  214   a  has a height A that is greater than the height B of the support ribs  218 . This embodiment may be desired when the baffle  214   a  naturally orients itself in a direction that is short of perpendicular to the central panel portion once the ridge vent is unrolled. The additional length (length A minus length B) is sufficient such that the baffle  214  is long enough to contact the roof when the ridge vent is installed and the baffle is at an angle of less than 90° to the central panel portion. In one exemplary embodiment, length A is about 0.75″ and length B is about 0.58″, meaning the baffle portions  214  are about 0.17″ longer than the support ribs  218 . This embodiment helps prevent the undesired entrance of wind driven debris, pests, etc. . . . under the baffle  214   a  by providing a good seal against the roof. This embodiment also provides a better interface between the roof and ridge vent for application of an additional caulking seal between the roof and the ridge vent, if desired. 
   In the embodiment of  FIG. 17 , the baffle  214   b  includes a deformable pliable portion  220  disposed towards a bottom edge of the main body portion of the baffle  214   b . This portion  220  may comprise an ultra-thin piece of plastic, such as 20–30 thousandths of an inch in thickness. In one embodiment, the main body portion of baffle  214   b  is about 70 thousandths of an inch in thickness. This thin portion may be formed by forming or leaving intact flash plastic formed at mold seams during the molding process. The pliable portion  220  may be conformed to the contours of the roof, and more specifically the roof shingles, when the roof ridge vent is installed, thus creating a seal between the roof and the baffle. Simple downward pressure on the baffles during installation should be sufficient to create the desired deformations in the pliable portions  220 . This seal may also be reinforced by caulking.  FIG. 18  is a partial front plan view of a roof ridge vent of this embodiment installed on a roof. As shown in  FIG. 18 , portion  220  conforms itself to the general contours of shingles  401  and spaces therebetween. This embodiment also helps prevent the undesired entrance of wind driven debris, pests, etc. . . . under the baffle  214   b , while also providing an improved interface for application of a caulk seal, if desired, or even replacing a caulk seal, thereby reducing labor and installation time. 
   The forming operation for forming the rollable ridge vent  201  can include injection molding, extrusion or compression molding, for example. In a preferred embodiment illustrated in  FIGS. 14 and 14A , the ridge vent is made by index injection molding. In such a preferred embodiment, a mold  302  having upper and lower mold sections, shown in phantom in  FIG. 14  is provided for forming a mold cavity. A quantity of polymeric material is disposed in the mold cavity and a first ridge vent section  301 , also shown in phantom, is formed in the mold cavity. Next, the first ridge vent section  301  is indexed so that it is substantially moved beyond the mold cavity but remains in contact with the mold  302 . As shown in  FIG. 14   a , a small stepped extension formed in the baffle  214  and central panel  202 , can remain in the mold  302 . Finally, a second quantity of polymer is disposed between the mold sections of mold  302  and a second ridge vent section is formed which is connected to the first ridge vent section  301 . The cooled first ridge vent section can then be rolled up in lengths containing about 20–50 feet of vent material, which is then packaged in a paper or polyethylene wrap. 
   As shown in  FIGS. 14 and 14A , the baffles  214  can be formed to have an initial orientation of at or about 90° to the central panel portion  202 . In some embodiment, the baffles are initially formed at an oblique angle with respect to the central panel portion  202 . The method of forming this embodiment of the rollable ridge vent is illustrated in  FIGS. 15 and 15A , with mold  302   a  and ridge vent section  301   a . The method of  FIGS. 15 and 15   a , other than the orientation of the formed baffle sections, is the same as the method illustrated by  FIGS. 14 and 14A  and is not repeated herein. 
   As noted above, the material selection for the rollable ridge vent will effect the memory of the polymer, as a more flexible material will not have as much memory as a more rigid material, and thus the orientation of the baffles  214  once the ridge vent is unrolled. Still further, the forming process can also factor into the orientation that the baffles  214  will take once the ridge vent is unrolled. For example, the orientation of the baffles  214  during the formation process can factor into their orientation once cooled, and thus following rolling and unrolling of the ridge vent. Also, stresses can be induced into the polymer material forming the baffles  214 , which could even cause the baffles to take an orientation that is greater than 90° relative to the central panel portion  202  once ejected from the mold process, and thus effecting the orientation of the baffles following rolling and unrolling of the ridge vent. One means of inducing these stresses is to cool the baffle portions  214  at a faster rate than, for example, the central panel portion  202 . This induced cooling rate difference can be achieved by adding water or other coolant lines proximate to the baffle portions  214  in the mold. 
   In one embodiment, an internal filter is coupled to the rollable ridge vent. An exemplary filter may be made of an untreated, unwoven fiberglass mesh. The filter may be attached to the vent by a heat staking process by which the support ribs  218  are melted into the filter material along the full length of the product. An exemplary filter is described in, for example, U.S. Pat. No. 6,149,517 to Hansen, the entirety of which is hereby incorporated by reference herein. The filter, of fiberglass mesh construction or the like, is provided beneath the central panel portion  202 , for filtering out insects, snow, rain, debris, etc., while allowing sufficient air flow therethrough to accomplish the purposes of the rollable ridge vent. 
   In one embodiment, the baffles  214  include weep holes (not shown) cut or otherwise formed therein proximate to bottom edges thereof, i.e., the edges that are oriented to rest on the roof shingles. The weep holes allow rainwater to pass through the baffles and drain down the sloped roof. In one embodiment, these weep holes are spaced about every four inches in the baffles  214  and are sized such that they remain open even if the baffles are oriented relative to the central panel portion at an angle less than 90°. In one embodiment, the weep holes are slots of about 0.2″ wide and 0.35″ high. 
   In a preferred embodiments, the roof ridge vent can be molded such that the baffles become generally parallel with (e.g., ±30°) the central panel when rolled. The baffles are then orientated in a more vertical position with respect to the central panel portion during installation, either manually or naturally by the shape or design of the baffle itself. Preferably, the baffles default to an installed position once the ridge vent is unrolled. 
   The baffles can be locked in vertical orientation by the use of clips, adhesive tape, or other securing means. The baffles can also be vertically oriented externally by imposing stresses, or reinforcing ribs, for example, in the right locations during the molding or fabrication of the ridge vent. In this manner, the baffles can be oriented in a flattened position when the vent is rolled, and then they can spring back once the vent is unrolled. These stresses, and/or reinforced portions of the vent, can help insure that the baffle is always naturally in a vertical orientation once installed, thereby reducing instances of improper installation. 
   In one embodiment, at least some of the support ridges are coupled to the baffles to help return the baffles to a desired orientation, such as perpendicular to the central panel portion, after the central panel is unrolled.  FIG. 20  is an enlarged, bottom perspective view of an embodiment of a rollable ridge vent  401 . With respect to many features, ridge vent  401  is constructed similarly to the ridge vent  201  described above. Ridge vent  201  has a central panel portion  402 , lateral edges  404  with baffles  414  pivotally coupled thereto, and support ribs  418 . Nail holes and/or channels  422  can be provided to provide predefined nail or fastener locations. Ridge vent  401  also includes slotted vent opening  410 . Unlike the ridge vent  201 , ridge vent  401  includes at least one, and preferably more than one, support ribs  418 A that are directly coupled to the baffles  414  and engage baffles  414 . Support ribs  418 A are preferably molded to the side walls of the baffles  414 , and not any portion of underside of top central panel portion  402  proximate to lateral edges  404 . However, for manufacturability purposes, in one embodiment, support ribs  418 A are coupled to both the inside side wall of baffles  414  and the central panel portion  402  at the lateral edges  404 , more specifically at the interior corners  420  formed by each baffle  414  and the bottom surface of the central panel portion  402 . Support ridges  418 A are preferably shaped as a spring, such as the accordion shape shown in  FIG. 20 , and as such extend when the baffles  414  are flexed to a more horizontal position when the rollable ridge vent  401  is rolled as described above. The support ribs  418 A provide spring tension to pull the baffle back towards a more vertical orientation (as shown) when the ridge vent  401  is unrolled. When the support ribs  418 A are coupled to both the inside wall of a baffle  414  and the central panel portion  402  at the lateral edge  404  as shown, the support ribs both extend and twist when the baffles  414  are flexed to a more horizontal position relative to the central panel portion  404 . 
   From the foregoing, it can be realized that this invention provides improved roof vents, methods of installation, and methods of manufacture. The roof vents of this invention have adjustable baffles, which can be laid flat for easier manufacturing and rolling, but which can be oriented in a vertical direction for providing negative pressure. Although various embodiments have been illustrated, this is for the purpose of describing, but not limiting the invention. Various modifications which will become apparent to one skilled in the art, are within the scope of this invention described in the attached claims.