1. Field of the Invention
The present invention relates to a connector for making a structural connection between a plurality of structural members joined at an angle. Specifically, the present invention relates to a multi-heel connector for securing a rafter, a ceiling joist, and blocking between rafters, and supporting wood walls in a single bracket connection. The design capacity of the multi-heel connector is sufficient to provide for superimposed vertical/horizontal/diagonal dead and live loads, including enhanced loads such as hurricane wind forces from contributing areas.
2. Description of Related Art
The connector of the present invention has particular utility with respect to light frame building construction that predominates the residential and light commercial construction market. Many different connectors are used in the art for joining structural members for building construction. These different connectors are designed to secure rafters and joists to the adjoining walls of a building structure. The connectors are provided with through-holes for fasteners that are driven through the connector and into the side faces of the structural members being connected.
In addition, the connectors for securing a rafter, ceiling joist, and supporting wood walls must now be designed for withstanding the upward and lateral loads developed by high winds, which differ by geographic location, and may include hurricane forces.
The prior art has provided numerous configured connectors to secure construction structural members to one another individually, particularly in the area of rafter-joist-wall attachments.
For example, in U.S. Pat. No. 3,967,908 issued to Snow, et al., on Jul. 6, 1976, titled “CROSS TIE SADDLE BRACKET,” a weld fabricated steel saddle bracket is taught having an elongated angle member with a portion adapted to abut the side of the top wall plate of a building and another portion adapted to lie on the top of the top wall plate, with two right angle members welded to the top portion of an elongated angle member. This is used as a cross tie saddle bracket for roof trusses. The weld attachment is such that one side edge of the horizontal flat portion is in planar alignment with the vertical side of the elongated member, and the end thereof is substantially flush with the end of the elongated angle member. A ceiling joist is adapted to be received in the saddle. A roof rafter is also carried in the saddle formed by the top of the elongated angle member, and the parallel spaced apart vertical portions of the first and second angle members.
Absent from this design, however, is an angled base segment or connector portion for supporting a rafter without a birdsmouth cut, as well as the angled tabs for attaching the blocking, and vertical tie down tabs.
In U.S. Pat. No. 4,669,235 issued to Reinen on Jun. 2, 1987, titled “SPACING AND SUPPORT CONSTRUCTION MEMBER,” a spacing and support construction member for wood frame construction is taught, providing precise positioning and support for cross members. The structure provides for an elongated center strip, nailing prongs, and multiple pairs of perpendicular projections at fixed locations along the center strip. The perpendicular projections are located on opposite sides of the center strip, and separated by a distance, which corresponds to the width of the cross member. A nailing tab extends outwards from the center strip, in the plane of the center strip. In a similar fashion to the '908 patent, absent from this design is an angled base segment or structure for supporting a rafter, as well as the angled tabs for attaching the blocking, and a vertical tie down tab.
In U.S. Pat. No. 4,976,085 issued to Krueger on Dec. 11, 1990, titled “CONSTRUCTION PLATE,” a construction plate is taught that includes a central body with a plurality of opposed legs directed outwardly, and a plurality of flanges mounted to bend lines relative to the central body to permit securement of the construction stud. The elongated central body has extended orthogonal forward legs. A right flange plate is bendable along a bend line mounted to the right side edge of the central body. Similarly, a left flange plate is integrally formed to the left side edge of the central body. Bending the flanges permits the mounting of a vertical stud member to a roof truss and a top plate stud. Although this brace accommodates an angled truss, it does so by providing brace-support via vertically extending members; there are no angled portions of the bracket to provide support for the truss. This brace also does not have tab or connection for the blocking member. The connection of the '085 patent refers to a truss support. Trusses are inherent structural members unlike individual rafter/joist construction; thus, the brace of the '085 patent does not provide for lateral loads which are within the truss itself.
In U.S. Pat. No. 6,295,781 issued to Thompson on Oct. 2, 2001, titled “STUD, TOP PLATE, AND RAFTER TIE DOWN,” a one piece metal connector is taught that ties the structural members of the roof and wall on a wood framed house. The rafter, side wall support and upper and lower top plate are all secured by the bracket. The plate tab is essentially comprised of several right angle bends that include extended legs with a plurality of nail holes to secure to the rafter, the side wall support, and the top plate. The bracket forms an anchor clip for securing the rafter and sidewall support, and is vertically symmetric such that by turning it upside down, it can be used on the opposite side of the rafter and sidewall support. However, the bracket does not provide a structure for holding the rafter at an angled position, eliminating the typical birdsmouth cut on the rafter, or an extension for performing a tie down capable of withstanding hurricane force winds. There is also no connection for a blocking member, and no provision for a lateral load between the rafter and joist.
In U.S. Pat. No. 6,837,019 issued to Collie on Jan. 4, 2005, titled “TORNADO AND HURRICANE ROOF TIE,” an angled riser includes a bridge angled to correspond with a selected pitch for a rafter. This design still does not include an angled bracket for supporting the bottom portion and weight of a rafter. The riser portion does not include a bottom piece for varying the rafter at different pitches. The rafter is secured to the bracket by nail holes in the raised bracket portion. There is also no connection for a blocking member, and no provision for a lateral load between the rafter and joist.
The present invention overcomes the disadvantages of the prior art by accommodating conventional joint construction at the heel with a multi-heel connector that addresses and facilitates the unique angles of attachment while securing the connection against high dynamic loads, such as hurricane force winds.
Other advantages of the present invention include a reduction in time to fabricate each rafter in handling, measuring, and layout, and omitting birdsmouth cuts.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide a multi-heel connector capable of adjoining the structural components at a heel joint in a building, including a rafter, joist, top wall plate, blocking member, and wall stud, in a single connector.
It is another object of the present invention to provide a multi-heel connector that adjoins the structural components of a building at a heel joint in a manner that withstands hurricane forces acting on the building's roof system.
It is a further object of the present invention to provide a multi-heel connector that can provide an angled surface area integral with the joist loop connection for greater rafter support.
It is yet another object of the present invention to provide a multi-heel connector capable of accommodating different roof pitches and joist widths in a single design, and one that is designed such that the adjoining rafter does not require a birdsmouth cut.
The above and other objects, which will be apparent to those skilled in the art, are achieved in the present invention which is directed to a multi-heel connector for connecting structural members in building roof structures, comprising: a loop portion for securing a joist to a rafter, the loop portion having a top surface and two side surfaces forming a cross-section at least as large as a cross-section of the joist such that the joist may be slidably placed within the loop section, the loop section including through-holes for fasteners for securing the joist to rafter; an angled base segment adjacent to one side of the loop portion, the angled base segment having a top surface for receiving a rafter, the top surface angled at a predetermined roof pitch; at least two vertical mounting tabs, one vertical mounting tab located adjacent the angled base segment, another vertical mounting tab located adjacent the loop portion on a side opposite the angled base segment; and a horizontal base platform section adjacent each vertical mounting tab, the base platform and tabs section having through-holes for fasteners for securing the multi-heel connector to a top wall plate.
The loop portion, the angled base segment, the vertical mounting tabs, and the base platform sections may be integrally formed into one connector, and may be formed from a single sheet of gage steel or other metal.
The loop portion sidewall adjacent the angled base segment is preferably terminated at the angled base top surface, and the loop portion sidewall opposite the angled base segment is preferably terminated at the top wall plate.
The multi-heel connector may further include at least one blocking tab for securing a blocking member adjacent the joist and rafter, wherein the blocking tab is adjacent the horizontal base platform section, the blocking tab including through-holes for fasteners to secure the blocking member.
The multi-heel connector may include a tie down tab extending from the loop portion, the tie down tab opposite the vertical mounting tabs and extending to or beyond the top wall plate. The tie down tab can extend to an exterior wall stud, and preferably comprises a material that when secured to the top wall plate, the end of the joist, and the side of the rafter, is sufficient to withstand hurricane force loads. It may also include a tab for securing to the rafter.
The fasteners traverse the through-holes to secure the structural members, and may comprise screws, nails or bolts.
The multi-heel connector may further include a riser key for mating with the angled base segment, the riser key adjusting the roof pitch for the rafter.
Additionally, the multi-heel connector may include a joist spacer for placement within the loop portion, the joist spacer decreasing the loop portion cross-section to accommodate a joist having a cross-section smaller than the loop portion cross-section.
The features of the invention believed to be novel and the elements characteristic of the invention are set forth with particularity in the appended claims. The figures are for illustration purposes only and are not drawn to scale. The invention itself, however, both as to organization and method of operation, may best be understood by reference to the detailed description which follows taken in conjunction with the accompanying drawings in which:
In describing the preferred embodiment of the present invention, reference will be made herein to
The present invention addresses the roof-to-wall heel connection in modern housing construction. It does this by combining in one bracket a connector that restrains from movement structural members exposed to vertical, horizontal, and diagonal dead and live loads, including loads originating from hurricane force winds.
In either roof framing design 20 or 30, rafters 12 extend at an angle from a top wall plate 14, shown here as a double plate, and are connected at an opposite end by a ridge board or beam 16. Top wall plate 14 is generally supported by the studs of exterior stud wall 18. Joists 24 extend horizontally from top wall plate 14. Joist 24 may overlaps and be extended by a joist or tie 26 if more length is required. Joist 24 may further be supported by an interior partition 28 if such support is needed. At each rafter-joist-exterior stud wall junction, blocking 32 is typically attached. The blocking 32 is supported approximately perpendicular to the angled rafter 12, and is secured between each rafter.
The multi-heel connector of the present invention is designed to attach rafter 12, joist 24, blocking 32, and exterior stud wall 18 in a single construction design. The multi-heel connector is preferably fabricated from a flat section of gage metal steel, or other solid, bendable material resilient enough to attach the structural members for building construction, and to withstand enhanced load forces. The attachment scheme to the structural members is preferably achieved by employing fasteners, such as screws, nails, and the like, through punch holes in the multi-heel connector plate.
The joint at the intersection of the roof rafter, joist, tie, blocking, wall plate, and wall studs is commonly referred to as the heel joint, where the multi-heel connector of the present invention is to be applied. The heel joint with all its individual structural members coming together forms one of the most significant joints in the entire building structure. It represents a point where the roofs dead and live loads are combined with wind and hurricane loads, exposing the heel joint to up lift and overturning forces in all directions. It is at this junction that the aforementioned loads are transferred to the exterior supporting bracing and shear walls.
Each structural member adjoining at the heel joint support particular superimposed loads which are combined at the multi-heel connector.
The description of an embodiment set out below to enable one to build and use an implementation of the invention is not intended to limit the enumerated claims, but to serve as a particular example thereof. Those skilled in the art should appreciate that they may readily use the conception and specific embodiments disclosed as a basis for modifying or designing other methods and systems for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent assemblies do not depart from the spirit and scope of the invention in its broadest form.
One aspect of the multi-heel connector of the present invention is to eliminate the common birdsmouth cut or seat on rafters. A birdsmouth cut is essentially a notch in the rafter to allow the angled rafter to mate securely with the top wall plate.
The rafter contact surface on the multi-heel connector of the present invention is designed to have a slope which provides for the selected, predetermined roof pitch. This weight-bearing rafter is supported on the sloped surface of angled base segment 56, and the load is transferred to the vertical legs on each side of the connector, in which one side bears directly on the wall plate, and the other side is supported on the top of the joist, thus providing a contact surface on the multi-heel connector for receiving the rafter and providing considerably much more contact surface area than the birdsmouth cut mating surface or seat. This reduces the pressure on the top wall plate. In this manner, the weight-bearing surface area is centered over the top wall plate, eliminating the eccentric load on the stud typically caused by a conventional birdsmouth cut on the rafter.
The multi-heel connector allows for direct fastening between the rafter and the joist, and the angled rafter contact surface transfers the rafter thrust force to the joist. Both the rafter and the joist are secured via the multi-heel connector to one another.
Opposite the mounting legs 52a,b are angled blocking tabs 58a,b respectively. Blocking tabs 58a,b are provided to secure blocking members between each joist and rafter. These blocking members provide a uniform distribution of the shear load from roof sheathing to the top of the wall plate, which is transferred to the building bracing wall system. This feature supports the lateral bracing of the building. It also eliminates wood splitting caused from the ubiquitous toe-nailing of the blocking to the top plate generally performed in the prior art. The blocking members may be attached to either side of blocking tabs 58a,b. The blocking tabs 58a,b may also be angled to allow for a roof overhang or a flush mount end.
The shape of multi-heel connector 50 allows for direct fastening between the rafter and joist. The shape of the multi-heel connector 50 takes the horizontal force component of the attached rafter and transfers this force to structural components of the connector and into the joist through the connector.
The fastening of tie down tab 62 resists upward forces from wind of even hurricane strength, and is made to be within building codes for such designs. Tie down tab 62 serves to anchor and fasten the entire roof system to the building shear wall, providing a stable structure under imposed loads. By extending tie down tab 62 over the wall sheathing, the roof system is assured greater attachment strength than the current prior art designs. Tie down tab 62 preferably includes a tab 62a to secure the rafter.
Each multi-heel connector may be fabricated of a single angle base structure for a desired, predetermined rafter placement angle, or can be fabricated into a low rise setting that accommodates the placement and attachment of a separate riser increment or riser key to make a preferred roof pitch. The riser key may be a separately fabricated angled block, such as a triangular attachment, that adjusts the angle of the roof pitch.
Similarly, the vertical mounting legs 54 on each side of the joist may be fabricated either for 5½ or 7½ inch lengths to accommodate 2″×6″ or 2″×8″ joists. Alternatively, the multi-heel connector's vertical mounting legs may be the larger dimension with an additional, separate joist spacer that would adjust for a 2″×6″ joist.
The present invention is adaptable to accommodate various sizes of rafters, joists, wall plates, studs, and sheathing, and is not limited to any particular dimensions for these structural components. The multi-heel connector is designed to provide a direct load path transfer through each structural member.
Preferably, the fabrication of the multi-heel connector of the present invention is simplified by constructing it from a single sheet of light gage metal, although the multi-heel connector may also be formed of separate components that are attachable in a structurally sound manner that ultimately performs the function of the multi-heel connector as claimed.
It is further noted that the tabs used for blocking members and the vertical mounting legs may be located on opposite sides of the multi-heel connector as currently shown in the figures.
While the present invention has been particularly described, in conjunction with a specific preferred embodiment, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. It is therefore contemplated that the appended claims will embrace any such alternatives, modifications and variations as falling within the true scope and spirit of the present invention.
Number | Name | Date | Kind |
---|---|---|---|
797474 | Walker | Aug 1905 | A |
2354801 | De Huff | Aug 1944 | A |
3091822 | Fiekers et al. | Jun 1963 | A |
3256030 | Banse | Jun 1966 | A |
3967908 | Snow et al. | Jul 1976 | A |
4410294 | Gilb et al. | Oct 1983 | A |
4669235 | Reinen | Jun 1987 | A |
4976085 | Krueger | Dec 1990 | A |
5109646 | Colonias et al. | May 1992 | A |
5230198 | Callies | Jul 1993 | A |
5335469 | Stuart | Aug 1994 | A |
5561949 | Knoth | Oct 1996 | A |
6295781 | Thompson | Oct 2001 | B1 |
6837019 | Collie | Jan 2005 | B2 |
6922967 | Collie | Aug 2005 | B2 |
6931813 | Collie | Aug 2005 | B2 |
7316098 | Sackett | Jan 2008 | B1 |
7971410 | Jerke | Jul 2011 | B2 |
20020124483 | Rosas | Sep 2002 | A1 |
20060150564 | Dufault | Jul 2006 | A1 |
20080244993 | Crumley | Oct 2008 | A1 |
20090090082 | Kawai et al. | Apr 2009 | A1 |
20110225924 | Carbonaro et al. | Sep 2011 | A1 |
Number | Date | Country |
---|---|---|
1672133 | Jun 2006 | EP |
WO 9740238 | Oct 1997 | WO |
WO 2008065437 | Jun 2008 | WO |
Entry |
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Simpson Strong-Tie Company, Inc., Wood Construction Connectors 2011-2012, C-2011, pp. 126, 181. |
United Steel Products Company, “Connect with Confidence,” USP Professional Design Manual and Product Catalog, 2011, pp. 64, 135, 56th Edition. |
Number | Date | Country | |
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Parent | 13971032 | Aug 2013 | US |
Child | 14089181 | US |