Abstract:
An insulation block is utilized with a corresponding baffle vent having a transverse width that will span several roof rafters, as is provided for use with manufactured housing. The insulation block includes uniformly spaced vertical ribs that extend from one edge of the insulation block to the opposing edge thereof to stiffen the insulation block which is formed of vacuum molded polyvinyl chloride film. After the baffle panel is placed on top of the roof rafters, which is before the roof sheeting is applied, the insulation block is attached to the wall top plate with the top edge of the insulation block placed into engagement with the baffle vent. The top edge of the insulation block is configured to mate with the undulating configuration of the corresponding baffle vent, fitting between transversely extending stiffening ribs on the baffle vent, to prevent insulation from entering the soffit area.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims domestic priority on U.S. Provisional Patent Application Ser. No. 60/905,524, filed on Mar. 6, 2007, the contents of which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates generally to attic vent baffles commonly used in residential building structures to allow ventilation flow from soffit vents into an attic space for venting from the attic, and, more particularly to an insulation stop that is installed at the exterior wall where the roof rafters and joists are supported to cooperate with the baffle vent to contain insulation to allow the passage of ventilation air in a manner that is particularly adapted for use in the manufactured housing industry. 
       BACKGROUND OF THE INVENTION 
       [0003]    Attic ventilation systems are typically used in residential buildings to provide proper ventilation of the attic space, which is desired to help prevent formation of condensation along the interior surface of the roof. Condensation can damage the attic insulation and the wooden structure of the building itself. Proper ventilation also helps to prevent premature melting of snow accumulated on a building roof, which can lead to the formation of ice on the roof that presents a safety hazard and can also lead to roof damage. Such attic ventilation systems will utilize vents placed into the underside of the soffit, which projects outwardly from the roof of the building and forms the overhang at the perimeter of the building roof. The intent of these attic ventilation systems is for air to travel through the soffit vents into the attic space and be discharged through an attic vent, which is typically placed at the apex of the roof. 
         [0004]    The use of insulation in the attic to provide a barrier to the transmission of heat between the occupied portion of the building structure and the unoccupied attic portion of the building can restrict, or even prevent, the flow of air from the soffits to the roof vent at the apex of the roof. The insulation can be packed along the joists of the roof trusses to the soffits and not allow a passageway for the movement of air past the insulation into the portion of the attic above the insulation. Known construction of the insulation material can include cellulose, rock wool, fiberglass and expanded foam, the latter being used most often in manufactured housing, i.e. housing constructed in a factory and transported to the job site instead of being constructed at the job site. To maintain a discrete passageway for the movement of from the soffit, past the insulation barrier, and into the upper portion of the attic for discharge through the roof vent, baffle vents have been provided for attachment to the interior side of the roof to keep the insulation separated from the interior surface of the roof deck. 
         [0005]    One embodiment of a baffle vent can be seen in U.S. Pat. No. 7,094,145, granted on Aug. 22, 2006, to Palle Rye, et al, and assigned to Brentwood Industries, Inc. The Rye baffle vent is stapled to the interior surface of the roof sheeting between the roof rafters and includes a tail portion that is bent in the vicinity of the soffit to form an insulation block that extends from the interior surface of the roof sheeting to engage the wall top plate. This baffle vent thus forms a barrier that prevents the movement of insulation into the soffit area and restricting the flow of air from the soffit into the attic. The structure of the baffle vent incorporates a series of convolution that are oriented parallel to the roof rafters to provide channels that define passageways for the movement of air past the insulation that is engaged against the baffle vent. In operation, the baffle vent utilizes the channels to keep the insulation away from the interior surface of the roof and establishes dedicated passages for the flow of air past the insulation along the interior surface of the roof sheeting. 
         [0006]    Earlier configurations of baffle vents can be seen in U.S. Pat. No. 4,446,661, granted to Jan Jonsson, et al, on May 8, 1984, in which a corrugated sheet is fastened to the vertical surfaces of adjacent roof rafters to provide a plurality of longitudinally extending passageways for the movement of air past insulation in the roof. A major consideration in the design and manufacture of such baffle vents is the cost of such structures, particularly when taking into consideration the large square footage of the roofs of some residential buildings. Consequently, baffle vents have been fabricated extensively of foam or plastic material in narrow sheets that form self-supporting structures that can be handled and manipulated into position between the roof rafters for attachment against the interior surface of the roof sheeting. In U.S. Pat. No. 5,341,612, issued to Gary Robbins on Aug. 30, 1994, a baffle vent structure is formed of a thinner foam sheet material and includes a reinforced structure to prevent the vents from collapsing during shipping, handling and installation, as well as to prevent collapsing of the vents from compacted insulation which often is blown into attic areas of a building against the underside of the baffle vents. 
         [0007]    Conventional residential construction affected at the job site will typically have the roof structure formed at the same time as the exterior shell of the building so as to get the building under roof to prevent the intrusion of foul weather into the interior of the building. The baffle vents described above are intended for use in such on-site construction techniques. Since the insulation is placed into the attic area long after the roof sheeting and shingles are added to the roof rafters, the baffle vents are formed to be placed between the roof rafters on the underside of the roof sheeting by attaching mounting flanged to either the vertical surfaces of the roof rafters, as is depicted in the aforementioned U.S. Pat. No. 4,446,661 to Jonsson, or the underside of the roof sheeting, as is depicted in U.S. Pat. No. 5,341,612 to Robbins. Generally, the baffle vents are installed as part of the installation of the insulation by contractors that specialize in the installation of insulation, rather than by the roofing contractor that will install the roof vent at the apex of the roof structure. 
         [0008]    Manufactured housing is constructed in a factory setting where there is no pressing need to have the roof structure completed before the interior portions of the house are completed. As a result, the baffle vents can be installed on top of the roof rafters before the roof sheeting is fastened to the roof rafters. Generally, manufactured housing is formed with the interior drywall sheeting applied to the bottom side of the ceiling joists to form the inside ceiling of the housing before the roof is completed. The roof sheeting is then attached to the top surfaces of the roof rafters, followed by the application of the exterior roofing materials, typically fiberglass shingles. Insulation can then be installed between the joists on top of the drywall. While blanket fiberglass insulation or blown loose cellulose or fiberglass insulation can be used, expanded foam is often used in manufactured housing construction. The expansion rate of the foam places a substantial pressure on the baffle vent and will often collapse the passageways, resulting in the interruption of the air flow from the soffit past the insulation layer. 
         [0009]    Blocking the opening between the joists and extending vertically from the wall top plate to the baffle vent beneath the roof sheeting is important to prevent the intrusion of insulation, particularly blown insulation or expanded foam insulation, into the soffit area, which would restrict the flow of ventilation air into the baffle vent for passage into the attic above the insulation blanket. In the manufactured housing industry, the insulation block is typically formed by rolling blanket fiberglass insulation material and stuffing the roll between the joists at the vicinity of the wall top plate. The baffle vent is then placed between the rafters before the insulation is blown in or expanded foam is injected into the area between the joists. 
         [0010]    An example of a baffle vent that is adapted for use in the manufactured housing setting can be found in U.S. Pat. No. 5,596,847, granted to Michael Stephenson on Jan. 28, 1997. This baffle vent is formed with longitudinally extending ribs that are spaced on eight inch centers so that the single panel can be used on rafters whether spaced sixteen or twenty-four inches apart. A score line is formed on one of the interior ribs so that the excess eight inch strip can be removed if the baffle vent is used on rafters spaced at sixteen inched. In U.S. Pat. No. 4,096,790, issued on Jun. 27, 1978, to Laurence Curran, the baffle vent is formed to span across multiple roof rafters with a panel hanging down to engaged the wall top plate and form a barrier to restrict the passage of insulation into the soffit area. In the Curran baffle vent configuration, mounting ribs are spaced at intervals corresponding to the roof rafter structure on which the baffle vent is to be applied. Thus, to be used with sixteen inch and twenty-four inch rafter spacings, the Curran baffle vent would have to be provided in two different models. 
         [0011]    The Stephenson baffle vent configuration, and particularly in the Curran baffle vent configuration, the spacing of the longitudinally extending ribs provides a wide span between the ribs to define large passageways for the movement of air along the interior surface of the roof sheeting. Unfortunately, this wide expanse of unreinforced passageway, particularly when the baffle vent is manufactured from foam or a thin plastic material to maintain cost considerations, is subjected to collapse, especially when used with expanding foam insulation techniques. If the passageway collapses, the baffle vent is not functional to allow the passage of air from the soffit past the insulation layer to the upper portions of the attic structure. 
         [0012]    Providing a combination baffle vent and insulation block has been recognized in the prior art. For example, the apparatus disclosed in U.S. Pat. No. 5,007,216, issued to David Pearson on Apr. 16, 1991, is a cardboard device that can be folded and stapled in place between the rafters and tacked to the wall top plate. As with such prior art devices, this baffle and insulation stop combination is intended for installation after the roofing materials have been attached to the rafters. The installation of the Pearson baffle would be cumbersome and time consuming with respect to use in the manufactured housing industry where production speed is essential. Furthermore, such cardboard construction is not sufficiently rigid to consistently withstand the pressures of expanded foam insulation. Other similar prior art combination baffle and insulation stop devices can be seen in U.S. Pat. No. 4,611,443, granted to Ralph H. Jorgensen, et al., on Sep. 16, 1986; in U.S. Pat. No. 4,581,861, granted on Apr. 15, 1986, to Matthew Eury; in U.S. Pat. No. 4,214,510, granted to Bruce Ward on Jul. 29, 1980; in U.S. Pat. No. 4,185,433, granted on Jan. 29, 1980, to James Cantrell; and in U.S. Pat. No. 3,863,553, granted on Feb. 4, 1975, to Bryce Koontz. 
         [0013]    In U.S. Pat. No. 6,357,185, issued to Keith Obermeyer, et al., on Mar. 19, 2002, a separate insulation stop member is disclosed as being cooperable with a baffle vent that is stapled to the underside of the roof sheeting to provide a barrier to the movement of insulation into the soffit area and to provide a flow of ventilation air from the soffit into the attic above the insulation layer. As with the combination baffle vent and insulation stop devices noted above, the Obermeyer insulation block is formed for installation after the construction of the roof materials onto the roof rafters. The cardboard insulation block is formed with various fold lines to fit between conventional 16 inch and 24 inch centered rafters and joists and includes staple tabs that fix the insulation block to the interior vertical face of the wall top plate, as well as to the vertical faces of the rafters and joists and the underside of the roof sheeting to fix the insulation block in place to resist the infiltration of insulation into the soffit. Furthermore, the Obermeyer insulation block is shaped to mate with the underside of the corresponding baffle block stapled to the underside of the roof sheeting, thus providing a barrier to insulation and establishing a flow path for ventilation air from the soffit into the attic past the insulation blanket. 
         [0014]    Accordingly, it would be desirable to provide an insulation block that would be cooperable with a corresponding baffle vent structure, the combination of which would be particularly adapted for use in the manufactured housing industry to establish and maintain passageways for the movement of air from the building soffit past the insulation layer into the upper attic area for discharge from the attic through a roof vent. It would also be desirable that the baffle vent be formed in a manner to resist collapsing when expanded foam insulation material, or other similar insulation material that exerts a force onto the baffle vent, is installed against the insulation stop. 
       SUMMARY OF THE INVENTION 
       [0015]    It is an object of this invention to overcome the disadvantages of the prior art by providing an insulation block that is cooperable with a baffle vent designed for use in manufactured housing. 
         [0016]    It is another object of this invention to provide an insulation block that can be attached to the wall top plate to project upwardly therefrom to prevent insulation from passing into the soffit area of a manufactured house. 
         [0017]    It is a feature of this invention that the insulation block is formed with undulating top edge that will mate with a corresponding baffle vent configuration. 
         [0018]    It is an advantage of this invention that the insulation block and corresponding baffle vent can be placed on the roof rafters before the roof sheeting is placed on the rafters. 
         [0019]    It is another feature of this invention that the insulation block is formed with alternating flat ribs and rounded valleys along the top edge thereof to mate with the configuration of the transverse width of the corresponding baffle vent. 
         [0020]    It is another advantage of this invention that the insulation block is sized to fit between standard roof rafters. 
         [0021]    It is still another feature of this invention that the insulation block is placed only between adjacent roof rafters irrespective of the width of the corresponding baffle vent. 
         [0022]    It is another feature of this invention that the baffle vent is formed with vertically extending ribs that extend from one edge of the insulation block to the opposing edge. 
         [0023]    If is yet another feature of this invention that the vertical ribs are spaced along the entire vertical height of the insulation block. 
         [0024]    It is another advantage of this invention that the vertical ribs stiffen the insulation block to make the insulation block easier to deploy and to be strong enough to resist the weight of the insulation pressing against the insulation block. 
         [0025]    It is a further feature of this invention that the vertical ribs extend uniformly along the entire transverse width of the insulation block. 
         [0026]    It is a further advantage of this invention that the vertical ribs on the insulation block provides adequate stiffness to the insulation block for ease of deployment in a manufactured house operation. 
         [0027]    It is yet another object of this invention to provide an insulation block for use in manufactured housing, which is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use. 
         [0028]    These and other objects, features and advantages are accomplished according to the instant invention by providing an insulation block that can be utilized with a corresponding baffle vent having a transverse width that will span several roof rafters. The insulation block includes uniformly spaced vertical ribs that extend from one edge of the insulation block to the opposing edge thereof to stiffen the insulation block which is formed of vacuum molded polyvinyl chloride film. After the baffle panel is placed on top of the roof rafters, which is before the roof sheeting is applied, the insulation block is attached to the wall top plate with the top edge of the insulation block placed into engagement with the baffle vent. The top edge of the insulation block is configured to mate with the undulating configuration of the corresponding baffle vent, fitting between transversely extending stiffening ribs on the baffle vent, to prevent insulation from entering the soffit area. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0029]    The advantages of this invention will become apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein: 
           [0030]      FIG. 1  is a top plan view of a portion of the baffle vent incorporating the principles of the instant invention, the depicted baffle vent corresponding to a first stamping of the larger full sized baffle vent vacuum molded during the manufacturing process; 
           [0031]      FIG. 2  is an end elevational view of the baffle vent segment depicted in  FIG. 1  and being arranged as an orthogonal projection of  FIG. 1 ; 
           [0032]      FIG. 3  is a perspective view of the baffle vent segment depicted in  FIG. 1 ; 
           [0033]      FIG. 4  is a partial schematic cross-sectional view depicting an elevational view of a representative manufactured housing structure utilizing a baffle vent according to the principles of the instant invention; 
           [0034]      FIG. 5  is a partial perspective view of a baffle vent mounted on the rafters of a roof structure according to the principles of the instant invention; 
           [0035]      FIG. 6  is an end elevational view of a portion of baffle vent depicted in  FIG. 5  at the wall top plate, looking in the orientation of the installed baffle vent; 
           [0036]      FIG. 7  is an enlarged end elevational view of a portion of the structure shown in  FIG. 6 ; 
           [0037]      FIG. 8  is a partial top plan view of an alternative ribbed configuration of the baffle vent; 
           [0038]      FIG. 9  is an enlarged partial side elevational view of the baffle vent depicted in  FIG. 8 ; 
           [0039]      FIG. 10  is an elevational view of an insulation block member incorporating the principles of the instant invention; 
           [0040]      FIG. 11  is an enlarged end view of the insulation block member depicted in  FIG. 10 ; 
           [0041]      FIG. 12  is a partial schematic cross-sectional view of a building structure having an insulation block member installed between a pair of ceiling joists at the wall top plate looking from the exterior of the building structure; 
           [0042]      FIG. 13  is a partial schematic cross-section view similar to that of  FIG. 12 , but showing a subsequent step of the installation of the insulation against the insulation block member, the ribs of the insulation block member being removed for purposes of clarity; 
           [0043]      FIG. 14  is a partial schematic cross-sectional view similar to that of  FIG. 13 , but showing the addition of the baffle vent having transversely extending ribs to interlock with the insulation block member; 
           [0044]      FIG. 15  is a partial schematic cross-sectional view similar to that of  FIG. 14 , but showing the addition of the roof sheeting to trap the baffle vent between the roof sheeting and the rafters; and 
           [0045]      FIG. 16  is a partial schematic cross-sectional view depicting an elevational view of a representative manufactured housing structure utilizing an insulation block member engaged with a baffle vent according to the principles of the instant invention to prevent insulation from infiltrating the soffit while establishing a flow path for ventilation air from the soffit past the insulation layer. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0046]    Referring to  FIGS. 1-7 , a baffle vent incorporating the principles of the instant invention can best be seen. The baffle vent  10  is preferably formed from polyvinyl chloride (PVC) film (not shown) having a thickness of about 12 to 16 mils through a conventional vacuum molding process in which the film is placed over a mold (not shown) and heated. A vacuum applied to the film draws the PVC film over a mold to cause the PVC film to assume the shape of the mold. In the preferred embodiment, the mold would have dimensions of about 39 inches by about 36 inches. Since the PVC film is supplied from a continuous roll, the baffle vent  10  can be formed in sequential segments  12 , which are then severed along the center of a rib  15 , as will be described in greater detail below, to form the complete baffle vent  10 . 
         [0047]    A single segment  12  is depicted in  FIGS. 1-3 . The preferred dimensions of the completed baffle vent  10  are about 39 inches high by 96 inches (8 feet) wide. The formation of such a baffle vent  10  would require the molded film to be severed after the third sequential segment, to form the baffle vent  10  at a temporary width of 9 feet. A 12 inch strip would then be cut off the baffle vent to provide the final 8 foot width dimension. The removed strip would then be recycled. Alternatively, the baffle vent could be formed at a 12 foot width which would correspond to four sequential segments before being severed without any waste to be recycled. Research has shown, however, that the 8 foot width is preferred in use because of the handling requirements and associated difficulties of transporting and installing the larger 12 foot wide baffle vent  10 . One skilled in the art will recognize that the size of the mold will depend on the physical parameters of the machinery operating the mold. Accordingly, other segment sizes are within the scope of the invention. For example, the width of the baffle vent  10  could be 10 feet so that a fifty foot long structure could be covered by five baffle vents mounted end to end. With the thickness of the material being at about 12 mils, the baffle vent  10  can be easily trimmed at the last rafter or simply overlapped. 
         [0048]    As can be seen in the drawings, the baffle vent  10  is formed with a series of parallel, longitudinally extending ribs  15  separated by a valley  20  defining an overall depth of the baffle vent  10 . The ribs  15  are spaced at four inch centers to provide the ability to be mounted on either sixteen or twenty-four inch roof rafter  32  spacings. With an eight foot width, the baffle vent  10  would span across seven roof rafters  32  placed at sixteen inch centers, and five roof rafters  32  placed at twenty-four inch centers, with the lateral edges  13  of the baffle vent being mounted on two end rafters  32  and either five or three intermediate roof rafters  32 , depending on the spacing. 
         [0049]    Each longitudinally extending rib  15  is formed with a flat top surface  17  having a width of approximately one and one-half inches to mate with the nominal width of the top surface of a roof rafter  32 , whether the roof rafter  32  is formed from 2×6, 2×8, or 2×10 lumber, as is best seen in  FIGS. 6 and 7 , except for the two end ribs  15  along each transverse edge of the baffle which are intended to span about half the rafter width to mate with an adjoining baffle  10 . Each valley  20  between the longitudinally extending ribs  15  is preferably formed in a semi-circular configuration to provide strength in cross-section to resist the expansive forces of the insulation materials, such as expanding foam insulation. Thus, each valley  20  has a rounded bottom surface  22  that is spaced vertically approximately one inch from the top surface  17  of the adjacent ribs  15 . Each valley  20  extends along the circular arc having a preferred radius of approximately seven-eighths of an inch from the center of the rounded bottom surface  22  through an angular deflection of approximately 68.5 degrees in each direction from the center of the bottom surface  22 , measured from the tangent at the center of the rounded bottom surface  22 , whereupon the valley  20  begins a reverse bend along a radius of approximately three-eighths of an inch to join with the horizontal, flat top surface  17  of the rib  15  on either side of the valley  20 . 
         [0050]    The above-described pattern is repeated on four inch intervals measured from the center of the flat top surface  17  of one rib  15  to the center of the flat top surface  17  of the next adjacent rib  15 , and consequently from the center of the rounded bottom surface  22  of each valley  20  to the center of the rounded bottom surface  22  of the next adjacent valley  20 . With this particular configuration of ribs  15  and valleys  20 , the baffle vent  10  can also mate with any oddly spaced roof rafter  32 , so long as the spacing from the next adjacent roof rafter  32  is a multiple of four inches. As an example, the end roof rafter  21  on a roof structure is not always placed at the same sixteen or twenty-four inch spacing as the remaining roof rafters  32 , because the overall length of the roof is not divisible by four feet. In such situations, the end rafter  32  will typically have an end spacing of eight, twelve or twenty inches. The baffle vent  10  can easily accommodate such an odd end spacing with a rib  15  that will mate with the top surface of the end roof rafter  32 . 
         [0051]    The configuration of the end elevation of the baffle vent  10 , as is best seen in  FIGS. 2 ,  6  and  7 , is such that the arched valleys  20  are supported by the adjacent ribs  15  that are pressed against the underside  34  of the roof sheeting  33  and present an arch to resist the forces exerted by the insulation that is pushing the baffle vent  10  against the underside  34  of the roof sheeting  33 . The arched shape provides a strong geometric shape that is resistant to collapse. Because the flat top surfaces  17  of the ribs  15  are typically pressed against the underside  34  of the roof sheeting  33  by the forces exerted by the engaged insulation material, each longitudinally extending rib  15  can be formed with a transversely extending relief depression  19  that provide a transversely extending path for any moisture to drain from between the rib  15  and the roof sheeting  33  and for air to pass from one valley  20  to the adjacent valley  20 . 
         [0052]    Where the ribs  15  are mounted on a roof rafter  32 , the pressure exerted by the fastening of the roof sheeting  33  onto the roof rafter  32  through the baffle vent  10  will flatten the small relief depression  19 . The relief depressions  19  are shown in a representative manner only in  FIGS. 1 and 2 . The actual location and positioning of the relief depressions  19  are a matter of design choice; however, the relief depressions  19  should not be aligned across the transverse width of the baffle vent  10 , which would make the handling of the baffle vent  10  more difficult as the baffle vent  10  would tend to bend across the aligned relief depressions  19 . 
         [0053]    As best seen in  FIGS. 4-7 , the typical roof structure is formed with ceiling joists  35  that function as attic floor joists and are oriented horizontally to support a ceiling structure  36  attached to the underside of the joists  35 . The roof rafters  32  are typically connected to the ends of the ceiling joists  35  and project upwardly therefrom at a prescribed angle to meet at an apex, forming with the ceiling joists  35  a conventional triangular configuration. The roof sheeting is then fastened to the top surfaces of the roof rafters  32  to form the roof structure  30 . The ceiling joists  35  and the roof rafters  32  may be supplied as a pre-assembled roof truss assembly having internal braces (not shown), or alternatively may be assembled at the construction site, and spaced at sixteen or twenty-four inch centers. 
         [0054]    The roof rafters  32  will extend downwardly past the ceiling joists  35  to form the eaves or soffits  31 , which are formed with vents  41  to allow air to flow into the soffits from the outside. The roof rafters  32  and the ceiling joists  35  typically rest on the wall top plate  39 . After the roof sheeting  33  is attached to the roof rafters  32 , the roofing surface, usually fiberglass shingles  37 , are attached to the upper side of the roof sheeting  33  to complete the construction of the roof structure. One of ordinary skill in the art will recognize that a roof vent (not shown) is usually placed at the apex of the roof to permit the movement of air from the attic  40 . 
         [0055]    Insulation  45  in the desired form is placed between and above the ceiling joists  35  to insulate the living area beneath the ceiling joists  35 . The ceiling material  36  will retain the insulation in the attic  40 . Preferably, the insulation  45  extends to the joinder of the roof rafters  32  and the ceiling joists  35  without extending into the soffits. The baffle vent  10  described above is positioned between the insulation  45  and the underside  34  of the roof sheeting  33 , as will be described in greater detail below. Air can then flow from the outside through the vents  41  in the soffit  31  through the valleys  20  in the baffle vent  10  defining passageways through the insulation  45  barrier along the underside  34  of the roof sheeting  33  into the attic  40  above the insulation. The air can then discharge through the roof vent (not shown). 
         [0056]    For the preferred use in manufactured housing, the baffle vent  10  is placed on top of the roof rafters  32  before the roof sheeting  33  is placed on the rafters  32 . The baffle vent  10  need only extend along the roof sheeting  33  for a length that is greater than the height of the insulation  45  along the roof sheeting  33 . For most insulation  45  configurations, a length of 39 inches is more than sufficient to extend into the attic  40  above the insulation  45 . The baffle vent  10  formed according to the principles of the instant invention does not require fastening to the tops of the roof rafters  32  when being installed. The formed shape of the PVC film provides a gripping tension in the baffle vent  10  to retain position on the roof rafters  32  without requiring fasteners. Furthermore, the properties of the PVC film stretched over multiple roof rafters along the  8  foot transverse width of the baffle vent  10  keeps the portions of the baffle vent  10  between adjacent roof rafters  32  from sagging. Once the baffle vent has been mounted on top of the roof rafters  32 , the roof sheeting  33  can then be installed on top of the baffle vent  10  and on top of the roof rafters  32  beyond the baffle vent  10 . The fasteners used to attach the roof sheeting  33  to the roof rafters  32  will easily pass through the baffle vent  10  and retain the baffle vent  10  in the desired location. 
         [0057]    Referring now to  FIGS. 8 and 9 , an alternative embodiment of the baffle vent  10  can be seen. By forming the material with transversely extending ridges  25  that extend across the ribs  15  and valleys  20  from one transverse end of the baffle vent  10  to the other, the baffle vent  10  acquires a substantial amount of stiffness to permit the baffle vent  10  to be more easily handled and installed. This convoluted cross-sectional shape, as is best seen in  FIG. 9 , establishes raised ridges  25  projecting upwardly from the flats  27  between the ridges, preferably at a height of approximately 60 mils. Accordingly, the convoluted cross-sectional shape of ridges  25  and flats  27  extending along the ribs  15  where mounted on the rafters  32  also provides for many relief depressions at the flats  27  along the length of the rafter  32  for the escape of moisture that might collect between the baffle vent  10  and the rafter  32  into the adjacent valley for discharge from the structure. 
         [0058]    Since the insulation, particularly expanded foam insulation often utilized in manufactured housing, will push the baffle vent panel  10  upwardly against the roof sheeting  33  between the rafters  32 , the longitudinally extending ribs  15  will engage the roof sheeting  33 , as depicted in  FIGS. 6 and 7 , with the rounded valleys  20  providing the passageway for the movement of air from the soffit  31  to the roof vent. The flats  27  in the ribs  15  between the rafters  32  allow moisture to escape from between the ribs  15  and the roof sheeting  33  into the adjacent valleys  20  for escape to the roof vent. With this configuration of the baffle vent  10  with transverse ridges  25  running from one transverse edge of the baffle vent panel  10  to the other transverse edge, the baffle vent  10  is sufficiently stiff to allow for ease of handling and a quick deployment onto the roof rafters  32  during manufacture of the building, and the ridges  25  provide a contact point against the roof sheeting  33  that minimizes the direct contact between the baffle vent  10  and the roof sheeting  33 , whether between the sheeting  33  and the rafter  32  or against the sheeting  33  between the rafters  32 . 
         [0059]    Referring now to  FIGS. 10-16 , an insulation block member  50  cooperable with the baffle vent  10  to establish a containment area between the ceiling joists  35  to keep the insulation from infiltrating the soffit area  31  in manufacturing housing construction. The insulation block member  50  is preferably formed from polyvinyl chloride (PVC) film (not shown) having a thickness of about 12 to 16 mils through a conventional vacuum molding process in which the film is placed over a mold (not shown) and heated, as described above with respect to the baffle vent  10 . The insulation block member  50  is preferably configured as a generally planar member  50  having vertical ridges  52  formed in a spaced-apart relationship along the transverse width thereof. The ridges  52  substantially increase the rigidity of the member  50  and provide the necessary resistance to bending when the insulation block member  50  is installed, as indicated in greater detail below. As with the baffle vent  10  depicted in  FIGS. 8 and 9 , the ridges  52  preferably have a depth of about 60 mils, which has shown to provide satisfactory results. 
         [0060]    The insulation block member  50  is formed with a top edge  53  that has curved depressions  54  cut into the member  50 , leaving at each laterally opposing side a height indicator  55  that will enable the person installing the insulation block member  50  to properly position the member  50  before attaching the member to the wall top plate  39 , as will be indicted in greater detail below. With the depressions  54  properly formed in the top edge  53 , the resulting shape will mate against the underside of the baffle vent  10  with the rounded bottom surfaces  22  of the valleys  20  thereof sitting within the depressions  54 . Preferably, the insulation block member  50  will have a vertical height that is in the range of 10-15 inches so that the insulation block member  50  can be utilized in different forms of building construction. Because of the need to mate with the baffle vent  10  when properly installed, the insulation block member  50  is preferably formed in either a 16 inch center configuration or a 24 inch center configuration. In the 16 inch center configuration, the insulation block member would have a transverse width of approximately 14½ inches to fit between ceiling joists formed with dimensional lumber placed on 16 inch centers. 
         [0061]    As can be seen in  FIGS. 12-16 , the insulation block member  50  is installed on the exterior of the wall top plate  39  in a manufactured housing environment. The insulation block member  50  would be positioned between adjacent ceiling joists  35  with the height indicators  55  positioned at the top surface of the rafters  32  onto which the baffle vent  10  will be mounted, as described above. With the height indicators  55  properly positioned, the installer staples or nails the insulation block member  50  to the wall top plate  39  with the ridges  52  preferably projecting toward the outside of the building structure to fix the insulation block member  50  in a vertical orientation affixed to the exterior of the wall top plate  39 . Insulation can then be blown in or injected between the ceiling joists  35  up against the insulation block member  50 , as is depicted in  FIG. 13 . The vertically oriented strengthening ridges  52  provide sufficient strength to allow the insulation block member  50  to resist bending outwardly. 
         [0062]    As is shown in  FIG. 14 , the baffle vent  10  can then be installed on top of the rafters  32 , as described above, with the valleys  20  of the baffle vent  10  resting in the depressions  54  on the top edge  53  of the insulation block member  50 , and the flat top surface  17  of the baffle vent  10  mounted on top of the rafters  32 . With the configuration of the baffle vent  10  having transverse strengthening ridges  25 , as depicted in  FIGS. 8 and 9 , the baffle vent  10  would be positioned on top of the insulation block member  50  with the top edge  53  of the member  50  being positioned between two strengthening ridges  25 . With the ridges  25  projecting approximately 60 mils below the top edge  53 , the insulation block member  50  becomes interlocked with the baffle vent  10 , the lowermost adjacent ridge  25  with respect to the top edge  53  restraining an outward deflection of the insulation block member  50 . Accordingly, where the insulation layer  45  is to be thicker than the height represented by the insulation block member  50 , as is depicted in  FIG. 16 , the baffle vent  10  is installed on the rafters  32  before the insulation is blown in or injected between the joists  35 . As depicted in  FIG. 15 , the roof sheeting  33  is typically installed on top of the rafters  32  and on top of the baffle vent  10  after the insulation layer  45  is installed into the building structure. 
         [0063]    As is best seen in  FIG. 16 , the combination of the insulation block member  50  engaged with the baffle vent  10  establishes a containment area for the insulation between the ceiling joists  35  inwardly of the wall top plate  39  and above the living area of the building structure. With the insulation prevented from infiltrating the soffit area  31 , a clear flow path is established for ventilation air passing through the soffit vents  41  and through the valleys  20  of the baffle vent  10  to be discharged from the attic above the insulation layer  45 . This baffle vent  10  and insulation block member  50  combination is particularly adapted for use in conventional manufactured housing environments in which the insulation block member  50  can be mounted on the outside of the wall top plate  39  before the roof is completed by the installation of the roof sheeting  33 , with the top edge  53  of the insulation block member  50  supported by the strengthening ridges  25  of the baffle vent  10 . 
         [0064]    While PVC film is the preferred material from which the baffle vent  10  and the insulation block member  50  are formed through the thermal molding, vacuum forming manufacturing process, one of ordinary skill in the art will recognize that other materials may be used in the manufacture of the baffle vent  10  and the insulation block member  50 . Sheet metals, thermoplastics, and composite materials composed of fibers impregnated with thermoplastic materials can all be used to form the vent baffle  10  and the insulation block member  50 . Sheet metals such as galvanized steel, stainless steel, aluminum and copper can be formed into vent baffles for use in the present invention. Thermoplastic materials which can be used in the present invention in addition to PVC film are, for example, polystyrenes, acetals, nylons, acrylonitrile-butadiene-styrene (ABS), styrene-acrylonitrile (SAN), polyphenylene oxides, polycarbonates, polyether sulfones, polyaryl sulfones, polyethylene, polystyrene, terephthalates, polyetherketones, polypropylenes, polysilicones, polyphenylene sulfides, polyionomers, polyepoxides, polyvinylidene halides, and derivatives and/or mixtures thereof. The particular material used may be dependent upon the desired end use and the application conditions associated with that use, as is well known in the art. 
         [0065]    It will be understood that changes in the details, materials, steps and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention.