WO2004022875A1

WO2004022875A1 - Framing member having reinforced end

Info

Publication number: WO2004022875A1
Application number: PCT/CA2003/001293
Authority: WO
Inventors: John Rice
Original assignee: Bailey Metal Products Limited
Priority date: 2002-09-05
Filing date: 2003-09-05
Publication date: 2004-03-18
Also published as: CA2401289C; US20040163356A1; CA2401289A1; AU2003266034A1

Abstract

The present invention is directed to a framing member for use in a steel framed flooring structure. The framing member has a U-shaped rectangular cross section with two parallel spaced apart flanges and a central web bridging the flanges and connected to one edge of each of the flanges. The central web has an extension on each end thereof, the extension extending beyond the flanges a distance of at least half the width of the flange.

Description

TITLE: FRAMING MEMBER HAVING REINFORCED END

FIELD OF THE' INVENTION

5 The present invention is directed to a metal framing member, particularly a metal floor joist, havir.g an integral reinforced end.

BACKGROUND OF THE INVENTION

3.0

The framing of buildings for residential dnά commercial construction has traditionally been accomplished using suitably dimensioned wood members. While the use of wood members makes the construction

15 relatively simple, the use of wood members has its shortcomings. The supply of lumber is getting scarcer and costs have increased during recent years . In addi ion wood can warp and go out of shape when it becomes wet as well as being susceptible to attack by

20 vermin of various kinds including termites.

In recent years buildings framed with sheet metal framing members have been employed. The use of sheet metal framing members provides advantages of dimensional 5 stability, ease of manufacture and conservation of natural resources among others. However the use of sheet metal members, particularly, joists has not gained widespread acceptance for various reasons. One sucn reason is that the ends of the joists where they are 0 attached to a vertical wall require that they be securely attached to the rim joist and that they be provided wi.th some rein rcement to provide the joist with the capability of supporting the load at the ends. In the past this has commonly beer, accomplished by using an L 5 shaped oraoke of a height about equal to the web of the joist. One leg of: the bracket is attached to the web at the end of the joist and the other leg is attached to the web t the rim joist. Another solution employs a section

- l - of steel stud or track equal in height to the height of the joist v/eb. The web of the stud or track section is, attached to the web of the joist and one flange of the stud is attached to the web of the rim joist. A variation on this is shown m U.S. Patent No. 5,625,99!:. issued May 6, 1997 to Byron Martin. This patent describes a special bracket shaped like a stud section for attaching this joist to the header. While these solutions provide the reσuired attachment and reinforcing for the floor joist, they significantly increase the labor time required to install the steel joist system. Consequently steel joist systems have not gained widespread acceptance among the raming trades .

A modified ledger or rim joist has recently been described m U.S. Patent No. 5,956,916 issued September 18, 1999 assigned to Steel Floor Ltd. m an attempt to overcome the above problems. The web of the ledger is provided with struck out tabs which extend perpendicularly inwardly of the v/eb at a regular spacing, typically 16 inches on center. The tabs act as a locating means and attachment means for the floor jorst as well as reinforcing the end of the web of the floor joist. While the modified ledger ₃01st makes the attachment of the floor joist easier, it also introduces new problems. The alignment of the ledger must be closely controlled so that the floor joists spanning the space between the ledge will be properly aligned with, the struck out tabs This will require additional labor time by the framing trades. Additionally, as the location cf the tabs are fi e at the time of manufacturing of the ledger, the flexibility m the spacing of the floor joists s limited. In some cases such as to avoid a service stack or to provide additional support below partition wauls, it may be necessary to adjust the spacing of the floor joist or to install additional joists. In addition if the load characteristics change, the 301st spacing required to support the load may change. Another situation where the floor joists will not properly align with the tabs is if th.e floor joist meets the ledger joist at other than right angles, e.g. 45 degree angles commonly encountered in bay window bump outs. In those cases, another means for providing t2ιe attachment and reinforcing of the end of the joist would be required such as the bracket or stud section described above, thus defeating the advantages of the modified rim joist .

There thus still remains a need for an easy to install means of attaching a steel framing members such as a to a supporting framing member such as a rim joist and reinforcing the end of the framing memb r.

SUMMARY OF THE INVENTION

The present invention is directed to a framing member for use in a steel framed structure. The framing member has a U-shaped rectangular cross section with two parallel spaced apart flanges and a central web bridging the flanges and connected to one edge of each of the langes. The central v/eb has an extension on each end thereof, che extension extending beyond the flanres a distance of at least half the width of the flange.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are illustrated in the attached drawings of which:

Figure 1 is a perspective view of a floor joist constructed in accordance with the present invention,- Figure 2 is a perspective view of the end of the floor joist of Figure 1; and Figure 3 is a perspective view of a floor constructed using the floor joist of figure ^"1; igure 4 is a perspective view of two floor joists of Figure 1 meeting over a beam; Figure 5 is a top plan view of the joists of Figure 4 ; and

Figure 6 is a perspective view of a second floor constructed using the floor joist of figure 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first preferred embodiment of a framing member, particularly a floor joist according to the present invention is illustrated in the attached figures generally indicated by the numeral 10.

The floor joist 10 has a generally C shaped cross section with a web 12 spanning two parallel flanges 14 at opposite edges of the web 1 . The opposite edge of the flanges 14 have an inwardly turned extension to strengthen the flanges when under load. The central web 12 is provided with extensions 16 on each end, the extension 16 having a height slightly less than the height of the web 12. The extension 16 extends beyond the end of the flange 14 a distance of at least half the width of the flange 14. Preferably the extension 16 extends beyond the end of the flange 14 a distance of about the width of the flange 14. When the joist is manufactured, the extensions 16 lie in the plane of the web 12 this allowing the joist to be easily stacked for transportation. In order to make the bending of the extension 16 easier, slots 18 are provided along the desired bend line 20 between the web 12 and the extension 16. The provision of the slots 18 also forces the extension 16 to be bent along this line.

In the construction of a floor, the rim or header joists 30 are attached to the wall, generally by being attached to the top plate of the wall or being directly attached to the vertical surface of the wall as is common in balloon framing and with walls formed from insulated concrete forms. The extensions 16 of the floor joists 10 are bent, generally perpendicular to the .web 12. The end of the joist 10 is placed in the opening of the rim .joist 30, butting the extension 16 against the web 32 of the rim joist 10. The extension 16 is then screwed to the web 32 of the rim joist 30 by suitable screws 36 and the flange 14 of the floor joist 10 secured to the flange 34 of the rim joist 30 by screw 36.

As illustrated in Figure 4, when two floor joists 10 meet over a beam 40, the extensions 16 reinforce the ends of the joists 10. In those situations, the webs 12 of the joists are attached to one another with suitable fasteners such as screws 36 or bolts. The flange 14 of the floor joists 10 are secured to the beam 40 by suitable fasteners such as screws 36.

As illustrated in Figure 5, the floor joists 10 of the present invention are of particular use where the joists 10 connect to the rim joist or header at other than right angles. In these circumstances, the extension 16 of the floor joist 10 is bent at an angle to match the angle between the floor joist 10 and rim joist 30. In this way, the extension 16 butts against the web 32 of the rim joist 30 and is easily secured to the web 34 of the rim oist 30.

The framing me ber of the present invention is manufactured using typical machinery such as roll forrters to bend the flanges from a suitable sized blank of metal. The extension and slots may be formed by a cutting machine either before or after the roll forming operation. Once produced the framing members are easily stackable one within another in the typical manner as there are no protrusions beyond the usual C shaped cross section . The dimensions of the framing members of the present invention are those typically used m metal forming. Floor joists produced m accordance with the preaent invention typicstlly have a depth of 8 to 14 inches, more preferably 8, 10 or 12 inches and the flanges are typically IY2 to 2 inches wide. The joist are typically formed of 14 to 20 gauge steel, most preferably 16 3- 18 gauge . _xn

As illustrated m Figure 3, the provision of the reinforced end is also of use m the construction of bridging members 50 which are used to interconnect two joists 10 intermediate their ends. The bridging member

15 50 is provided Λ(i h tne extensions 52 on either end h-.ch are bent over to allow the bridging member 50 to be attached to the webs 12 of the joists 10 by screwing through the extensions 52 and into the web 12 of the ₃01st 10 The length of the bridging mem er s the same

20 as the spacing between the joists 10, typically 16 inches, although other lengths are possible depending upon the design of the flooi'. In order to allow the bridging member 50 to fit between the inwardly turned extensions of the flanges 14, the height of the bridging

?5 member is selected to be equal to or less than the spacing between the inwardly turned extensions Typically for & and 10 inch joists, the height of the bridging member will be 6 inches. This allows the bridging member to fit in the space and be formed using

30 the machinery generally used for 6 inch steel f aming members .

As illustrated m Figure 6, the extensions may also be used to reinforce the ends of lintels 6 formed by 35 attaching two jo-ists 62 of the required length together back to back, each of the joists 62 having the extensions at either ends. Tne extension 64 are bent over to e attached to the studs 66 framing the opening 68 bridged by the lintel 60.

The framing member, particularly the floor joist of the present invention provides for numerous advantages over those of the prior art. The securement of the floor joist to the rim joist does not require the use of additional support members such as brackets or short sections of metal studs, thus resulting in significant labour savings. Similarly, the connection of two floor joists to one another over a beam does not require additional support members, also resulting in labour savings. The floor joists of the present invention are also easily adaptable to situations where the floor joists meet the rim joist or header at other than right angles .

In addition to its use as a floor joist or framing member for a lintel, the framing member of the present invention may also be utilized in other framing applications in residential or commercial construction. For example, the provision of the extensions on the end of the central web may also be utilized in framing of roofs, particularly for use in a roof rafter whi.ch frames into a hip for a hip roof or into the ridge of a metal framed roo .

Although various preferred embodiments of the present invention have been described herein in detail, it will be appreciated by those skilled in the art, that variations may be made thereto without departing from the spirit of the invention or the scope of the appended claims .

Claims

1. A framing member for use in steel framed flooring 5 structures, the framing member comprising a metal member having a generally U shaped rectangular cross section with two parallel spaced apart flanges and a central v/eb bridging the flanges and connected to one edge of each of the flanges, the central web being an extension at either 0 end thereof, the extension extending beyond the flanges a distance of at least half the width of the flange, the extension being bendable to allow it to butt against a supporting frarring member in a steel framed structure.

5 2. A f aming member according to claim 1 wherein the framing member is a floor joist.

3. A floor joist according to claim 2 wherein the floor joist is provided with slots between the web and the n extension to allow the extension to be bent more easily.

4. A floor joist according to claim 3 wherein the extension extends beyond the web a distance of about the width of the flange. 5