AU736249B2 - Floor joist system and support member therefor - Google Patents

Description

31 January, 2001 Regulation 3.2

AUSTRALIA

Patents Act 1952 COMPLETE SPECIFICATION FOR A STANDARD PATENT

(ORIGINAL)

Name of Applicant: Actual Inventors: Address for Service: Invention Title: Dietrich Industries, Inc.

1 Mellon Bank Center, Suite 2226, Pittsburgh, Pennsylvania 15219, United States of America Larry Randall DAUDET Gregory S. RALPH Edmund L. PONKO DAVIES COLLISON CAVE, Patent Attorneys, 1 Little Collins Street, Melbourne, 3000.

Floor joist system and support member therefor The following statement is a full description of this invention, including the best method of performing it known to us: P.\OPER\DH\62679-99 divl.doc-02/02/01 -2- FLOOR JOIST SYSTEM AND SUPPORT MEMBER THEREFOR BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The subject invention relates to building components and, more particularly, to floor joists and floor systems fabricated from metal.

DESCRIPTION OF THE INVENTION BACKGROUND 20 Traditionally, the material of choice for new residential and commercial building framing construction has been wood.

However, over the years, the rising costs of lumber and labor required to install wood framing components have placed the dream of owning a newly constructed home out of the economic 25 reach of many families. Likewise such increasing costs have contributed to the slowing of the development and advancement of urban renewal plans in many cities. Other problems such as the susceptibility to fire and insect damage, rotting, etc.

are commonly associated with wood building products.

Additional problems specifically associated with wooden floor joists include cost, availability and quality. These problems

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are particularly acute with respect to larger joists which must be harvested from large old growth forests which are becoming depleted.

In recent years, in an effort to address such problems, various alternative building materials and construction methods have been developed. For example, a variety of metal stud and frame arrangements hae been developed for--use in residential and/or commercial structures. U.S. Patent No.

3,845,601 to Kostecky discloses such a metal wall framing system. While such system purports to reduce assembly costs and the need for welding or separate fasteners, several different parts are, nonetheless, required to complete the wall frame system which can be time consuming and expensive to inventory and assemble. Such components must also be manufactured to relatively close tolerances to ensure that they will fit together properly thereby leading to increased manufacturing costs. Other metal stud systems for fabricating walls are disclosed in U.S. Patent No. 3,908,328 to Nelsson, U.S. Patent No. 4,078,347 to Eastman et al., U.S. Patent No.

20 4,918,899 to Karytinos, U.S. Patent No. 5,394,665 to Johnson, 11:: 'and U.S. Patent No. 5,412,919 to Pellock et al. Such patents .are particularly directed to wall system constructions and do not address various problems commonly encountered when installing floor and/or ceiling joists and support structures therefor within a building.

Conventional floor construction methods typically comprise installing "header" members on the top of support walls that may be fabricated from, for example, concrete blocks, wood or metal studs. The header members typically S 30 comprise wood beams that are supported on edge on the wall.

Other wood beam members, commonly referred to as joists, are used to span from wall to wall between the headers and are usually connected to the headers by nails. The joists are typically arranged parallel to each other with 16" or 24" between their respective centers, depending upon the load characteristics that the floor must accommodate. A sheathing 3 material such as plywood is then nailed to the upper edges of the joists to form the floor surface. To prevent the joists from inadvertently twisting or moving laterally, small pieces of wood, known as blocking pieces, are commonly nailed between adjacent joists to form, in many instances, X-shaped braces between the joists. Insulation is sometimes installed between the joists and sheathing, drywall, plasterboard, etc. is then applied to the bottom of the joists to form a ceiling for the space located under the floor joist system.

While these materials and floor construction arrangements have been used for many years in residential and commercial construction applications, they have many shortcomings that can contribute to added labor and material costs. For example, when connecting the joists to their respective headers, the carpenter must first measure and mark the headers to establish the desired joist spacing. This additional step increases the amount of construction time required to install the floor system and, thus, results in increased construction costs. After the headers are installed, the joists must be oo 20 properly nailed to the headers. If the carpenter has access to the opposite side of the header from which the joist is to be installed, the nails are hammered through the header into the end of the respective joist. If, however, the carpenter cannot access the opposite side of the header, nails must be inserted at an angle (commonly referred to as "toenailing") through the joist and into the header. Care must be taken to avoid inadvertently splitting the joist and to ensure that the nails extend through the joist and into the header a sufficient distance. Such attachment process can be time 00. 30 consuming and may require the use of skilled labor which can also lead to increase construction costs. If toenailing is not structurally acceptable, another piece, called a joist 0- hanger must be added which also increases labor and material costs.

It is also often desirable to install ductwork, piping, electrical wires, etc. within the floor joist system so that 4 they do not occupy living space and are concealed by the ceiling material that is attached to the bottom of the joists.

To accommodate those elements that must span multiple joists, passageways and/or holes must be provided through the joists.

The number, size, and location of such passageways/holes must be carefully considered to avoid compromising the structural integrity of the joists. FurtHlrmore, the blocking members may have to be moved or eliminated in certain instances to permit the ductwork and/piping to pass between the joists. In addition, cutting such passageways/holes into the joists at the construction site is time consuming and leads to increased labor costs. Another shortcoming associated with such floor joist systems is the difficulty of installing insulation between the joists due to the blocking members.

As noted above, there are many shortcomings associated with the use of wood floor joists and headers. In an effort to address some of the above-noted disadvantages, metal beams have been developed. For example, U.S. Patent No. 4,793,113 to Bodnar discloses a metal stud for use in a wall. U.S.

20 Patent No. 4,866,899 to Houser discloses a metal stud that is used to support wallboard panels for forming a fire-rated wall S: and is not well-suited for supporting structural loads. U.S.

.Patent No. 5,527,625 to Bodnar discloses a roll formed metal member with reinforcement indentations which purport to provide thermal advantages. The studs and metal members disclosed in those patents, however, fail to address many of the above-noted shortcomings and can be time consuming to install. Furthermore, many of the metal beams, studs, etc.

disclosed in the above-mentioned patents typically must be cut •e 30 in the field using hand tools. Such cuts often result in sharp, ragged edges which can lead to premature failure of the component when it is placed under a load.

In an apparent effort to better facilitate installation of various beams, U.S. Patent No. 3,688,828 to Nicholas et al.

discloses the use of L-shaped brackets to facilitate attachment of eaves boards and rafters to a C-shaped channel.

While such arrangement may reduce assembly costs at the construction site, such brackets must be welded or separately affixed to the C-shaped channel which is time consuming and leads to increased manufacturing and fabrication costs.

Furthermore, significant skill is typically required to properly layout and align the brackets.

Currently, metal floor jotst material is generally costcompetitive with wood material. However, the nuances of assembling existing metal joists generally make them noncompetitive when compared with wood joist arrangements.

Thus, there is a need for a floor joist that is relatively inexpensive to manufacture and install.

There is still another need for a joist support system that can be easily installed without the need for skilled labor.

V Another need exists for a joist header that has a plurality of joist attachment locations pre-established e thereon thus eliminating the need for the installers to layout each header.

eo: 25 Yet another need exists for a joist header that is relatively lightweight and that can be used to support metal o *o or wooden joists in predetermined locations.

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P \OPER\DH62679-99 divl.doc-02/02/01 -7- SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a member for supporting a plurality of joists, said member comprising: a C-shaped rim member fabricated from metal and having a web and two leg portions; a plurality of joist attachment tabs integrally formed in said web, said joist attachment tabs being provided at predetermined distances on said web relative to each other; and at least one reinforcing rib corresponding to each said tab and provided in said web adjacent said corresponding tab.

In another aspect, there is provided a member for supporting at least one joist on a support structure, said member comprising: a C-shaped rim member fabricated from metal and having a web and two leg portions; *ooo P:'OPER\DH62679-99 dil.dc-02/O02OI -8means for attaching a plurality of joists to said web, said means for attaching being integrally formed in said web and being provided at predetermined distances on said web relative to each other; and reinforcing means in said web adjacent each said means for attaching.

In another aspect, there is provided a floor joist system, comprising: at least two metal joists, each said joist having two ends and being substantially C-shaped such that each said joist has a central web portion and an upper and lower leg portion protruding from said central web portion, each said central web portion having at least one opening therethrough having a circumference and a reinforcing lip extending around said circumference; at least one metal joist rim, each said joist rim being substantially C-shaped and having a rim web and an upper and lower rim leg protruding therefrom, said rim web sized such that said end of a corresponding metal joist can be abutted substantially perpendicularly to said rim web of said corresponding joist rim and be received between 15 said upper and lower rim legs thereof, said rim web of each said joist rim further having at least one attachment tab integrally formed therein corresponding to each said end of each P:\OPER\DH\62679-99 div.doc-02/0201 -9said corresponding joist and being substantially parallel to said corresponding end for attachment thereto, said rim web further having at least one reinforcing rib therein adjacent to each tab; and at least one blocking member having a body portion sized to extend between two said joists, said blocking member having a body portion and two opposing end tabs integral with said body portion, each said end tab corresponding to one of said joists for attachment thereto.

o• BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying Figures, there are shown present preferred embodiments of the invention wherein like reference numerals are employed to designate like parts and wherein: FIG. 1 is a partial perspective view of a floor system of the subject invention; FIG. 2 is an inside isometric view of a joist rim of the present invention; FIG. 3 is an outside isometric view of the joist rim of Figure 2; FIG. 4 is a cross-sectional view of a portion of the joist rim of Figures 2 and 3 taken along line IV-IV in Figure 2; FIG. 4a is an outside isometric view of another embodiment of the joist rim of the present invention; FIG. 5 is cross-sectional view of a joist of the present invention; FIG. 6 is a partial cross-sectional view of a floor system of the present invention wherein a duct has been inserted through openings in the joists; FIG. 7 is another partial cross-sectional view of a floor S system of the present invention wherein insulation material is supported between the joists; 25 FIG. 8 is another partial perspective view of the floor system of the present invention illustrating a portion of an upper wall structure attached thereto; ""FIG. 9 is a partial perspective view of a floor system of the present invention attached to a wall structure having a door or window opening therein; *FIG. 10 is a partial perspective view of the floor system of the present invention supported between two dissimilar wall structures; FIG. 11 is a partial perspective view showing a floor support system of the present invention attached to a concrete block support wall; FIG. 12 is a perspective view of another embodiment of a blocking member of the present invention; and Figure 13 is a partial end assembly view showing the blocking member of Figure 12 attached to two joists.

DETAILED DESCRIPTION OF TUE PREFERRED EMBODIMENTS Referring now to the drawings for the purposes of illustrating the present preferred embodiments of the invention only and not for the purposes of limiting the same, the Figures show a floor system 10 of the present invention that may be used advantageously in residential and commercial applications, alike. More particularly and with reference to Figure i, a floor system 10 of the present invention may include at least two headers or joist rims 20 that are supported on corresponding wall structures 12. As shown in Figure i, the wall structure 12 may comprise a C-shaped metal top track member 14 and a plurality of metal wall studs 16 that are attached to the top track member 14 by conventional fastener screws and techniques. Those of ordinary skill in 20 the art will appreciate that the floor system 10 of the present invention may be successfully employed with a variety of different wall or other supporting structures that may be fabricated from wood, concrete block, etc.

The floor system 10 may also comprise a plurality of joists 40 that are adapted to span between wall structures 12 9e and have their respective ends attached to the joist rims CFigure 1 only shows one joist rim 20 and its corresponding wall structure 12. The reader will appreciate that the joists 40 may span from one wall structure 12 to another wall or 30 support structure (not shown) and are attached to corresponding joist rims 20 in a manner described in further detail below.

.9 Figures 2 and 3 depict a joist rim 20 of the subject invention. The joist rim 20 may be fabricated from, for example, cold rolled galvanized steel or other suitable metal, 11 the gauge of which may be dependent upon the amount and types of loads that the floor system 10 must support. For example, for a floor system that is designed to support loads of forty pounds per square foot, the joist rim 20 may be fabricated from 16 gauge cold rolled steel. As can be seen in Figures 1- 3, a joist rim 20 may be substantially C-shaped when viewed from the end and have a central rim web portion 22 and an upper rim leg 24 and a lower rim leg 26. In the above example, the distance may be, for example, ten inches. The skilled artisan will appreciate, however, that the overall size of the joist rim 20 will be somewhat dependent upon particular design characteristics, such as floor loading, joist spacing, deflection criteria, etc. The reader will also appreciate that the joist rim 20 may be initially formed utilizing conventional roll forming techniques. In a preferred embodiment, the lower leg 26 may be longer than the upper rim leg 24. The lower leg 26 may extend from the web 22 at a distance of, for example, 2.5" to facilitate easy attachment of the joist rim 20 to all types of supporting structures.

20 As can also be seen in Figures 2 and 3, a joist rim is provided with a plurality of integrally formed attachment tabs for affixing the ends 41 of the joists 40 thereto. The attachment tabs 30 may be provided in the joist rim 20 at any desired interval (distance in Figure However, those S 25 of ordinary skill in the art will appreciate that it may be advantageous to provide the attachment tabs 30 at intervals of o o 16", or 24". It will be further appreciated that, depending upon the particular wall structure construction, wall studs 16 are often spaced at such intervals. Thus, by o. 0 30 integrally forming the attachment tabs 30 at those intervals, oooothe joists 40 can be arranged to overlay corresponding studs 0. 16 in the wall structure 12 for load distribution purposes.

In the alternative, due to the load distribution capabilities 00.0of the joist rim of the present invention, the studs forming the wall structures could be dissimilarly spaced relative to the joists. That is, the unique and novel characteristics of 12 the present rim joist can eliminate the need for vertically aligning wall studs over corresponding joists. The skilled artisan will further appreciate that by forming an attachment tab 30 at every eight inch interval, the installer can choose to affix the joists 40 at any of those intervals 8", 16", 24") The attachment tabs 30 of~the present invention are preferably integrally formed in the web portion 22 of the joist rim 20 by punching three-sided, rectangular flaps or tabs out of the web 22 and bending the tabs 30 at a predetermined angle relative to the plane of the web 22. In a preferred embodiment, the tabs 30 are bent at 900 relative to the web 22 (angle in Figure However, the tabs could be oriented at other suitable angles depending upon the application. The tabs 30 may be punched into the web 22 utilizing conventional metal punching techniques and equipment. Also, to facilitate quick attachment of the joists to the tabs 30, a series of fastener holes 34 may be punched through the web to accommodate conventional sheet 20 metal fasteners such as, for example, self-drilling screws.

For example, in applications wherein distance A is approximately i0", the length of a tab 30 may be 6" (distance and the width of a tab 30 may be 1" (distance By way of additional examples, the tabs 30 may be 1" x 4"11 for joist rims adapted to support joists that are 7.25", 8" and 9.25" high or tabs 30 may be 1" x 6" for joist rims adapted to support joists that are 10", 11.25", 12" and 14"11 high. The skilled artisan will appreciate that the integrally formed tabs 30 may be provided in a variety of different sizes and 30 shapes without departing from the spirit and scope of the present invention. It will be further appreciated that when the integral tabs 30 are formed and bent to a desired angle relative to the web portion 22, an opening 36 corresponding to each tab 30 is formed through the web 22 of the joist rim which may also be used to permit the passage of wires, pipes, etc. through the joist rim 13 In some applications, it may be desirable to attach the joists to the upper legs 24 of the joist rim 20. To facilitate such attachment, a plurality of holes 25 are prepunched through the upper leg 24 for receiving fastener screws therethrough. By way of example, as can be seen in Figure 2, the centerlines of the holes 25 may be equally spaced on each side of the tab centerline approximately 1" (distance However, other hole arrangements may be provided.

Similarly, to facilitate attachment of the rim joist 20 to the structure 14 below, a series of pre-punched holes 27 may be provided in the lower leg 26. For example, holes 27 may be spaced approximately 4" from the centerline of the attachment tab 30 (distance as shown in Figure 2.

However, other hole arrangements may be employed. Those of ordinary skill in the art will appreciate that when the joists are attached to the leg 24, there is generally no need to attach the ends of the joists 40 to the tabs 30 in many loading applications. Conversely, in many cases, if the ends of the joists 40 are attached to the tabs 30, there is no need 20 to attach the joists to the leg 24 of the joist rim 20. Such i" arrangement also eliminates the need for joist hangers.

Also, reinforcing ribs 38 may be provided on each side of *each opening 36 to provided reinforcement to the web 22 and to permit the attachment tab 30 to function as a structural connection between the joist rim 20 and the corresponding joist 40. We believe that for many applications, such reinforced integral tabs provide sufficient strength to negate the need to fasten the bottom leg of the joist to the bottom leg of the joist rim which can be difficult to make in the 30 field. At least one, and preferably two, ribs 38 are embossed into the web 22 as shown in Figures 2, 3, and 4. The ribs 38 ":may comprise indentations that are embossed into the outer surface 23 of the web 22. Ribs 38 may be wide and 1 deep and be spaced, for example, approximately 1" from the edges of each corresponding opening 36 (distance See Figure 4.

Ribs 38 may, for example, be 5" long for joist rims 20 that 14 have webs 22 that are 7.25", 8" and 9.25" long or ribs may be 7"1 long for joist rims 20 with larger webs 22. The size, shape and location of ribs 38 may be advantageously altered depending upon the loads applied to the joist rim 20 and the size of the joist rim 20. Those of ordinary skill in the art will appreciate that such ribs 38 and tabs 30 may also eliminate the need to employ joist web stiffeners, which could lead to lower joist fabrication costs. The ribs 38 may be formed into the web 22 utilizing conventional roll forming techniques. It will be further appreciated that the rim joist of the present invention has sufficient load distribution characteristics to generally eliminate the need for extra parts commonly associated with prior joist header arrangements. For example, the unique capabilities of the present rim joist 20 eliminates the need to use double 2" x 4" plates to distribute the load from the joists to the wall studs a common practice employed in the past.

Another embodiment of the rim joist of the present invention is illustrated in Figure 4a. In this embodiment, the rim joist 20' is essentially identical in construction to the rim joist 20 described above, except for the configuration of the ribs 38'. As can be seen in Figure 4a, the ribs 38' are provided at an approximately 450 degree angles (angle I"QI in Figure 4a) relative to the edges of the joist rim 20' and the attachment tabs 30'. Furthermore, the diagonal ribs 38' may be crossed as shown to provide additional strength and stiffness to the web portion 22' Multiple cross arrangements may be employed between the tabs As can be seen in Figure 4, the attachment tab 30 may be advantageously provided with a series of pre-punched punched during fabrication of the joist rim 20 as opposed to being punched in the field with hand tools) holes 34. By prepunching the holes 34 at desired locations, the installer is assured that the fasteners used to fasten the tab 30 to a joist 40 are placed in the proper location to ensure adequate structural integrity of that connection. Prepunching also 15 reduces the amount of labor required for installation purposes. By way of example, an attachment tab 30 that is 6" long and 1" wide may have three attachment holes 34 therein with their centerlines being approximately 1.5" apart. Those holes may also be aligned on the centerline of the tab Such arrangement and number of fastener holes 34 may be dictated by joist size and composition, loading conditions, etc.

While the skilled artisan will appreciate that the joist rim 20 of the present invention may be advantageously used in connection with wood joists 2" x 2" x 10", 2" x 12", etc. beams) and other metal beams, the joist rim particularly works well in connection with metal joists 40 of the type depicted in Figures 1, 5, and 6. As can be seen in those Figures, a joist 40 is C-shaped and has a web portion 42 and an upper leg 44 and a lower leg 46. Joists 40 may be fabricated from cold rolled galvanized steel or other suitable metal utilizing conventional roll forming techniques and be sized to accommodate various loading characteristics. For 20 example, a joist 40 sized for use in connection with the joist rim example discussed above may have a height of approximately S. 10" (distance and the upper and lower legs (44, 46) may .each be approximately 1.75" long (distance The skilled artisan will appreciate that the sizes of the web 42 and the upper and lower legs (44, 46) can vary depending upon the application and may or may not be symmetrical. In addition .the ends of the upper and lower legs (44, 46) are bent inwardly to provide the joist 40 with reinforcing lips 47). See Figure 5. For example, reinforcing lip 45 may be approximately 5/8" long (distance and be bent at an angle of approximately 900 relative to the upper leg 44. Similarly, reinforcing lip 47 may be approximately 5/8" long (distance or some other length and may or may not be symmetrical.

Preferably, joists 40 are sized such that the ends 41 thereof may be abutted against the web portion 22 of a corresponding joist rim 20 such that the lower leg 46 of the 16 joist 40 is received on the lower leg 26 of the joist rim and the upper leg 44 of the joist 40 is under the upper leg 24 of the joist rim 20. To attach the end 41 of the joist 40 to the joist rim 20, conventional fasteners, such as for example, self-drilling screws are inserted through the holes 34 in the corresponding tab 30 and into the web portion 42 of the joist If desired, the lower leg-46 of the joist 40 may be fastened to the lower leg 26 of the joist rim 20 by conventional fasteners. Similarly, the upper leg 44 of the joist 40 may be fastened to the upper leg 24 of the joist rim by inserting conventional fastener screws through prepunched holes 25 in the upper leg 24.

To permit utility elements such as heating, ventilation and air conditioning ducts, wires, piping, etc. to pass through the joists 40, each joist 40 may be provided with at least one opening 50 through their respective web portions 42. As can be seen in Figure 1, openings 50 may be oval-shaped to accommodate a variety of differently shaped components. A plurality of openings 50 may be provided through each joist 20 40. The size, location and number of such openings 50 may be oo dependent upon considerations such as loading characteristics, and the location and the size of the ducts, pipes, etc. that S"must be accommodated. To provide the web portion 42 of the joist 40 with additional strength and reinforcement around ooo S 25 each opening 50, a rim 54 of material is formed around the circumference 52 of each opening 50. Rim 54 may be formed *oo around the opening 50 by a two progression, one hit, wipe bend draw process. For example, in a joist 40 that has legs (44,46) that are each 1.75" long, the rim 54 may also extend o 30 inwardly approximately 11/16" (distance See Figure Figure 6 depicts the floor system 10 described above wherein a section of duct work 60 extends through aligned openings 50 in the joists 40. We have found that the configuration and size of rim 54 permits relatively large openings to be provided through the joist web. For example, a joist manufactured from cold rolled galvanized steel and having a length of 16 feet 17 and that is supported at its ends and placed under a load of forty pounds per square foot can be successfully provided with up to eight equally spaced openings 50 that are approximately 6.25" wide and 9" long. We have also found that the rim 54 prevents the creation of sharp edges that are inherent to punched holes. Thus, rim 54 provides a safer work environment as well as reduces the need for protective devices such as grommets to be installed within such openings to prevent inadvertent damage to the ducts, wires, pipes, etc. that pass through the opening.

Also, to enable insulation 70 fiberglass batting, rigid foam, etc.) to be efficiently installed between joists the web portion 42 of each joist 40 may be provided with a plurality of retainer holes 62. As can be seen in Figure 7, the retainer holes 62 are adapted to receive the ends of Ushaped wire retainers 64 therethrough. Each end of the wire retainers 64 may be provided at an angle sufficient to retain it within the retainer hole 62 after it is inserted therein.

Other retainer configurations could also be used without 20 departing from the spirit and scope of the present invention.

However, in this embodiment, the retainer wires 64 are first installed and thereafter the insulation is placed over the retainers 64 from the upper side of the joists. After the insulation 70 is installed over the retainers 64, the floor sheathing material 100 may be installed. Such insulation installation method eliminates the need for installers to work from an often cramped crawl space to install the insulation.

Also, the unique U-shaped configuration of the retainers 64 enables insulation that is substantially as deep as the joists 30 to be easily installed while standing on the upper legs of the joists.

:The present floor joist system 10 may also comprise unique and novel preformed blocking members 80 that are installed between joists 40 to provide lateral support thereto. A blocking member 80 may be preformed from cold rolled galvanized steel or other suitable metal in a C-shape 11 utilizing conventional metal stamping methods. As can be seen in Figures 1, 6 and 7, a blocking member 80 may have a web portion 82 and two upstanding legs 84. A connection tab portion 86 that is substantially coplanar with the web 82 is formed at each end of the blocking member 80. At least one, and preferably two, fastener holes 88 are provided through each connection tab portion 86 -web to enable conventional fasteners such as sheet metal screws 90 to be inserted therethrough into the lower legs 46 of corresponding joists 40. As shown in Figure i, the blocking members 80 may be slightly staggered relative to each other to enable the connection tab portions 86 of each blocking member 80 to be attached to the corresponding lower joist legs 46 without interfering with each other. The skilled artisan will readily appreciate that such blocking members 80 do not interfere with the installation of insulation 70 between the joists 40 and/or with the passage of ducts, wires, pipes, etc. through the openings 50 in the joists 40. See Figures 6 and 7. Also, by utilizing preformed blocking members 80, the often time consuming task of cutting and notching the blocking members within the field may be avoided. Furthermore, the skilled artisan will appreciate that cuts made in the field with hand tools are often ragged which can be hazardous to the installation personnel and which can result in premature o 0 failure of the part. Thus, by preforming the blocking members 80,installation time is reduced, the blocking members are •co e safer to handle and are more structurally sound. In addition, by pre-punching fastener holes in the connection tab portions 86 of the blocking members 80, the installer is assured of 30 proper placement of fasteners through the connection tab portion.

To install the floor system illustrated in Figure 1, the joist rims 20 are supported on the upper wall tracks 14 of the corresponding wall structures 12. Fasteners are inserted through the lower legs 26 of the of the joist rims 20 to attach the joist rims 20 into the upper wall tracks 14 as 19 shown. Thereafter, the joists 40 are installed between the joist rims 20 at desired intervals. It will be appreciated that because the joist rims 20 are provided with the integrally formed attachment tabs 30 at predetermined intervals, the installers do not have to "layout" each joist rim 20 at the construction site, thus, reducing the amount of time required to install the floor system 10. The end 41 of each joist 40 is abutted against the corresponding joist rim adjacent the appropriate corresponding attachment tab and the attachment tab 30 is attached thereto by conventional fasteners inserted through holes 34 in the attachment tab If desired, the lower legs 46 of each joist 40 may be attached to the lower leg 26 of the corresponding joist rim with fastener screws. Similarly, the upper legs 44 of the joists 40 may be fastened to the upper leg 24 of the corresponding joist rim 20 through the preformed holes After the joists 40 have been installed, blocking members may be installed as described above at appropriate intervals.

Thereafter, the U-shaped retainers 64 may be installed in the 20 holes 62 in the joists 40, if insulation is desired. The insulation 70 is then installed on the retainers 64. To complete the floor structure 10, conventional sheathing material 100 such as plywood may be screwed to the top legs 44 of the joists and the joist rim. If desired, ductwork, piping, wiring may be inserted through the openings 50 in the joists 40 and through the openings 36 in the joist rims .The skilled artisan will also appreciate that the floor system of the subject invention may be used in multiple story applications as shown in Figure 8. As can be seen in that 30 Figure, after the sheathing 100 is attached to the joists and joist rim 20, an additional C-shaped "lower" wall track 110 may be attached to the sheathing 100 by fastener screws.

An appropriate collection of vertical C-shaped wall studs 114 may be affixed to the lower track 110 in a known manner to form a wall structure 120. It will be further appreciated that the wall structure 120 may be fabricated from 20 I I conventional wood studs in a known manner.

Figure 9 illustrates use of a floor system 10 of the present invention in connection with a wall structure 200 that has an opening 210 for a door or window therein. In this embodiment, a C-shaped header 220 is placed over the top track 202 of the wall structure 200 and is attached to the wall studs 204 that are arranged in-back-to-back fashion adjacent the window or door opening 210. A plurality of fasteners, preferably screws, are employed to attach the header member 220 to the studs 204. Header member 220 may be fabricated from cold rolled galvanized steel or other suitable metal and have a web portion 222 that is sized to fit over the upper wall track member 202 and two legs 224 that may extend, for example, 8" from the web 222.

The floor system 10 of the present invention is wellsuited for use in connection with support structures of dissimilar construction. For example, as can be seen in Figure 10, a joist rim 20 may be supported on a standard wall structure 12 that is fabricated from metal tracks 14 and metal studs 16. The joist rim 20 may be attached to a top track 14 of the wall structure 12 by conventional fastener screws and techniques. In addition, a second joist rim 20' may be supported on a wall structure 300 that comprises a series of concrete blocks 302. The skilled artisan will appreciate that S 25 the joist rim 20' is attached to the wall structure utilizing conventional fasteners and construction techniques. After the *oee joist rims (20, 20') have been installed, a series of joists 40 are suspended therebetween and attached thereto in the above-described manners. Blocking members 80 may also be S 30 installed between the joists 40. If desired, retainer members and insulation (not shown) may be installed between the joists as described above and conventional sheathing material 100 may be affixed to the joists Figure 11 depicts the floor system 10 of the present invention wherein one of the joist rims 20 is attached to the side of a wall structure 300 that is fabricated from concrete 21 blocks 302. Those of ordinary skill in the art will appreciate that the joist rim 20 may be attached to the wall structure 300 utilizing conventional concrete screws 304 or other suitable fasteners.

Figures 12 and 13 depict an alternative blocking member 400 of the present invention which can be used tc provide lateral support to the joists 40. As can be seen in those Figures, the blocking member 400 is essentially C-shaped and has a web portion 402 and two leg portions (404, 406) that are integrally formed with the web portion 402. An attachment tab 408 is provided at each end of the blocking member 400 such that each attachment tab 408 is substantially perpendicular relative to the web portion 402. In addition, to provide the blocking member 400 with additional strength, reinforcing rims 410 are formed on each leg (404, 406). To facilitate easy installation, a series of attachment holes 412 may be provided through the attachment tabs 408. Also, the web 402 of each blocking member 400 may have one or more holes 414 therein to permit wires, piping, etc. to pass therethrough. The blocking 20 members 400 are then affixed to the joists as shown in Figure 13 by conventional fasteners 420.

.Thus, from the foregoing discussion, it is apparent that the present floor system solves many of the problems associated with prior floor systems. The unique and novel aspects of the present floor system components provide many advantages over prior floor system components. For example, i the joist rim of the present invention provides improved load distribution and structural integrity characteristics when compared with prior header arrangements. This improvement may 30 eliminate the often tedious task of vertically aligning each joist over a wall stud. Also, in some applications, the overall strength of the joist rim may negate the need for headers at window and door openings. Furthermore, as was discussed above, the various components of the present invention provide a safer floor system that is more economical and easier to install than prior floor systems. In addition, 22 the present floor system is particularly well-suited for use in connection with a variety of different floor structure configurations and constructions. Those of ordinary skill in the art will, of course, appreciate that various changes in the details, materials and arrangement of parts which have been herein described and illustrated in order to explain the nature of the invention may be-'made by the skilled .artisan within the principle and scope of the invention as expressed in the appended claims.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that that prior art forms part of the common general knowledge in Australia.

o* 00 0°°°99 e *e 23

Claims (9)

1. A member for supporting a plurality ofjoists, said member comprising: a C-shaped rim member fabricated from metal and having a web and two leg portions; a plurality of joist attachment tabs integrally formed in said web, said joist attachment tabs being provided at predetermined distances on said web relative to each other; and at least one reinforcing rib corresponding to each said tab and provided in said web adjacent said corresponding tab.

2. The joist support apparatus of claim 1 wherein at least one said reinforcing rib is oriented at an angle relative to at least one said tab.

3. The joist support apparatus of claim 2 wherein said angle is approximately t ,,forty-five degrees.

4. The joist support apparatus of claim 2 wherein at least two said reinforcing ribs 15 intersect each other. The member of claim 1 wherein each said tab has a plurality of fastener holes therethrough.

6. The member of claim 1 further comprising at least one opening through said web.

7. A member for supporting at least one joist on a support structure, said member ::comprising: a C-shaped rim member fabricated from metal and having a web and two leg portions; means for attaching a plurality of joists to said web, said means for attaching being integrally formed in said web and being provided at predetermined distances on said web relative to each other; and reinforcing means in said web adjacent each said means for attaching. P:OPER\DHi62679-99 diI.doV-O0201

8. A floor joist system, comprising: at least two metal joists, each said joist having two ends and being substantially C-shaped such that each said joist has a central web portion and an upper and lower leg portion protruding from said central web portion, each said central web portion having at least one opening therethrough having a circumference and a reinforcing lip extending around said circumference; at least one metal joist rim, each said joist rim being substantially C-shaped and having a rim web and an upper and lower rim leg protruding therefrom, said rim web sized such that said end of a corresponding metal joist can be abutted substantially perpendicularly to said rim web of said corresponding joist rim and be received between said upper and lower rim legs thereof, said rim web of each said joist rim further having at least one attachment tab integrally formed therein corresponding to each said end of each said corresponding joist and being substantially parallel to said corresponding end for attachment thereto, said rim web further having at least one reinforcing rib therein adjacent 0* 15 to eachtab; and at least one blocking member having a body portion sized to extend between two said joists, said blocking member having a body portion and two opposing end tabs o S• integral with said body portion, each said end tab corresponding to one of said joists for attachment thereto.

9. The floor joist system of claim 8 further comprising a sheathing attached to said joists. $0 The floor joist system of claim 8 wherein each said joist has at least one hole o. therethrough to accept a corresponding end of a retainer therethrough that extends between oo• two said joists to retain an insulating medium therebetween.

11. A member for supporting a plurality of joists, substantially as hereinbefore described with reference to the drawings. DATED this 31 st day of January, 2001 Dietrich Industries, Inc. By DAVIES COLLISON CAVE Patent Attorneys for the applicant