As shown in
The joist hanger 1 has a seat 4 for receiving a portion of the bottom surface 5 of the I-Joist 2. The I-Joist 2 is made up of top and bottom chords 6 and 7 and a web 8 between them. The bottom chord 6 has a bottom surface 5, a top surface 9 and side walls 10.
As shown in
As shown in
As shown in
Preferably, only one such inwardly projecting guide 17 or 18 is formed in each side wall 11 or 12. Preferably, the joist hanger 1 is designed to be used with an I-Joist 2 and the inwardly projecting guides 17 and 18 both hold the I-Joist 2 away from the side walls 11 and 12 and down on the seat 4, without the use of additional fasteners, as shown in
As can be seen in
As shown in
As best shown in
As shown in
As best shown in
In a first form shown in
Flaring the embossment in this manner makes a stronger and stiffer inwardly projecting guide 17 or 18.
As shown in
In a similar form, shown in
In both forms, where an I-joist 2 is used, the point 24 where the embossment 19 projects inwardly the farthest lies just above where the top surface 9 of the bottom chord 7 of the I-Joist 2 would lie when the I-Joist 2 is sitting properly in the joist hanger 1. See
The dimple or embossment 19 in both forms can take a variety of shapes. As described above, and as shown best in
Shaping the inwardly projecting guides 17 and 18 in this manner aids in the installation of the I-Joist 2, while providing greater resistance to removal of the I-Joist 2. As shown best in
As shown in
As shown in
In the first preferred form of the invention, shown in
In the second preferred form of the present invention, shown in
Since I-Joists 2 are generally made from wood, the dimensions of the I-Joist 2 can change somewhat due to their relative moisture content. Further, I-Joists 2 from different manufacturers, although designed with the same nominal dimensions will vary in dimension somewhat. The inwardly projecting guide 17 or 18 of the present invention is able to accommodate I-joists 2 of varying bottom chord 7 dimensions because . . .
The preferred embodiments of the inwardly projecting guides 17 and 18 shown in
However, while it is preferred to primarily use a single embossment to form the inwardly projecting guides 17 and 18, other operations could be used to form the inwardly projecting guides 17 and 18.
In the preferred forms of the guides 17 and 18, which are formed primarily by embossing and has an opening 27, the point 24 farthest away from the side wall 11 or 12 is fairly sharp, which allows them to cut into the bottom chord 7 of the I-Joist 2 to better restrain it against uplift forces.
The embossing of the inwardly projecting guides 17 and 18 provides strength when the hanger 1 is made out of light gauge steel, as in the preferred form.
As shown in
In the preferred embodiment show in
In the preferred embodiment for use with an I-Joist 2, the inwardly projecting guides 17 and 18 preferably extend 0.3105 inches inwardly from the side walls 11 and 12 at points 24. The tabs 65 project inwardly 0.165 inches from the side walls 11 and 12. The projection 31 in the seat 4 projects 0.1 inches.
When installing an I-Joist 2, the force with which the side walls 11 and 12 spring back after the bottom chord 7 has bypassed the point 24 at which the guides 17 and 18 project inwardly the farthest, helps to push the I-Joist 2 down on the upwardly extending projection 31 in the seat 4. An alternate embodiment of the upwardly extending projection 31 in the seat 4 is shown in
Preferably, no nails are used to attach an I-Joist 2 to the joist hanger 1. This eliminates another opportunity for rubbing to occur between the nail and the I-Joist 2 or between the nail and the joist hanger 1.
The side walls 11 and 12 can also be kept away from the bottom chord 7 of the I-Joist 2 by spacing them from each other a selected distance, such that the only portion of the side walls 11 and 12 that is likely to come into contact with the I-Joist 2 or other type of joist member are the inwardly projecting guides 17 and 18 of the side members 11 and 12.
The joist 2 is formed with substantially parallel opposed side faces 56 defining a first selected width 57 for said joist 2, the opposed side walls 11, 12 of the hanger 1 are substantially planar members 11, 12 disposed in parallel relationship, and spaced from each other a selected distance that is greater than said first selected width 57 of the joist 2, wherein the inwardly projecting guides 17, 18 of the side walls 11, 12 are sufficiently rigid to hold the joist 2 of the first selected width 57 entirely away from the side walls 11, 12 except at the inwardly projecting guides 17, 18, when the side faces 56 of the joist 2 are substantially parallel with the side walls 11, 12 of the hanger 1.
Alternatively, and preferably as shown in
In the preferred embodiment, the bottom chord 7 of the I-Joist 2 is formed with substantially parallel opposed side walls 10 defining a first selected width for the I-Joist 2. These side faces 10 of the bottom chord 7 lie parallel to the side faces 10 of the top chord 6.
In the preferred embodiment, the opposed side walls 11 and 12 of the joist hanger 1 are substantially planar members disposed in parallel relationship, and spaced from each other a selected distance that is greater than the first selected width of the I-Joist 2. See
In the preferred embodiment, the inwardly projecting guides 17 and 18 of the side walls 11 and 12 are sufficiently rigid to hold the I-Joist 2 of said first selected width entirely away from the side walls 11 and 12 of the joist hanger 2 except at the inwardly projecting guides 17 and 18, when the side walls 10 of the I-Joist 2 are substantially parallel with the side walls 11 and 12 of the joist hanger 1.
As shown in
As shown in
In the preferred embodiment, an opening 37 is formed by punching the seat 4 in such a manner that the material of the seat 4 is drawn by the punch upward from the seat 4 and out of the plane of the seat 4. As the material is drawn upward, it breaks, causing sharp edges to be formed at the edge of the opening 37. The member 31 formed thereby, is preferably curled 90 degrees out of the seat 4.
Thus, none of the material of the seat 4 is removed from the hanger 1, but rather portions of the seat 4 around the opening 37 are bent out of the plane of the seat. The upwardly-curled, jagged edges of the member 31 have led the inventors to call the preferred form the starburst locator. The jagged edges of the starburst locator 31 grab onto the I-Joist 2 or other member as it is being installed, such that it is fixed in the seat 4.
While the upwardly projecting portion 31 is preferably formed as above, it could also be formed as triangular tab 31′ or any number of sharp projecting tabs known in the art.
The inwardly projecting guides 17 and 18 of the side walls 11 and 12, and the upwardly extending member 31 of the seat 4 cooperate during installation to hold the I-Joist 2 away from the side walls 11 and 12, such that it is seated properly, as shown in
As shown in
As shown in
In one emodiment, the joist hanger 1 is only attached to the header 3 or support member by means of fasteners 40 that run through the back flanges 38 of the hanger 1 and directly into the header 3. Another way to reduce floor squeak would be to form the hanger 1 such that it has no members or portions that were disposed above the top surface 42 of the header 3, when the hanger 1 is installed.
Joist hangers 1 are broadly classified into four categories, face-mount hangers, top-flange hangers, wrap-around hangers and saddle hangers, depending, primarily, on how they are attached to the header 3. The improvements of the present invention relating to the inwardly projecting guides 17 and 18 and the positioning of the I-Joist 2 can be used with all types of joist hangers 1.
Top flange hangers add a top flange 43 member to the typical face-mount hanger, this top flange 43 is formed to engage the top surface 42 of the header 3, such that the hanger 1 can hang from the header 3. A hanger with typical top flanges 43 is shown in
Wrap-around hangers are similar to top-flange hangers. They add another member to the top flange that engages the back surface of the header, to make an even stronger connection. Saddle hangers consist of two joist receiving members that are connected by a member that wraps over the top of a header.
The joist hanger 1 of the present invention can be formed with top flanges 43 that hook over the top of the header 3; however, the inventors have found that squeaking in the connection can be lessened if no top flanges 43 are present. Top-flange hangers generally rely substantially on the top flange 43 hooked over the top surface 42 of the header 3 to carry the load. The inventors have found that top-flange hangers, having only a few nails in the back flanges near the top of the hangers, tend to stretch over time. This stretching is partly a result of the top flange digging into the header or rounding off the edge of the header. This stretching is also due to the straightening of the bend in the top flange and back flanges. This stretching creates looseness in the connection that can lead to excess noise.
Furthermore, as shown in the Callies '248 and the Tschan '548 patents, with typical top flange hangers, the distance between the lowest nail in the back flange and the seat is quite far. This distance between the seat and the lowest anchor point of the hanger in the header allows the seat of the hanger quite a bit of play to pull away from the front surface of the header under load. This can also lead to squeaking.
In the present invention, by driving a plurality of spaced fasteners 40 through the back flanges 38 into the front surface 39 of the header 3, the opportunity for the hanger 1 or portions of the hanger 1 to stretch under load is reduced. See
However, the inventors have also found that with the preferred rigid, inward-projecting guides 17 and 18, the lowest fastener 40 in the back flange 38 cannot be too close to the seat 4. See
Another reason for removing the top flange is that top flanges generally lift the floor sheathing away from the top surface of the header. The inventors have found that a problem with the prior art is that using nails to attach the top flange of the hanger to the header lifts the floor sheathing or sub-flooring even higher above the surface of the header. This creates gaps or space between the top surface of the header and the bottom surface of the floor sheathing. Forming the floor with these gaps can lead to looseness of fit over time and rubbing of parts as the building settles. Using relatively green lumber further exacerbates this problem.
However, installers like to use hangers with top flanges, and the inventors have found a way to accommodate the needs of the installers with the needs to produce floors with minimal squeak.
As shown in
Recognizing this, the inventors have adopted a compromise solution by providing low-profile, top flanges 43 on the hanger 1 that are relatively thin and narrow, such that in some situations they can actually be pushed into and become flush with the top surface 42 of the header. See
The top flanges 43 can be formed so that they are small enough to be pushed into the top surface 42 of headers 3 made from such lumber as Douglas Fir-Larch and Southern Pine. In some instances, the top flanges 43 may be pushed into the top surface 42 merely by installation of the sub-flooring 46. The installer could also pound the top flange 43 into the top surface, such that the top flange is flush with the top surface 43 of the header 3. See for example
The dimensions of the top flanges 43 or self-jigging tabs is dependent on a combination of factors, including the strength and thickness of the material from which the hanger 1 is made. As stronger materials are used to make the hanger 1 and the top flanges 43, the top flanges 43 can be made smaller.
If desired, nail prongs could be added to the top flanges 43. These nail prongs could be used to more securely fasten the hanger 1 to the header 3 while the joist hanger 1 is being connected to the header 3 with nails 40 or other fasteners. The nail prongs would be formed out of the metal of the top flanges 43. The nail prongs would be driven into the header by striking them with a hammer.
Nail prongs 51 can be added to the back flanges 38 of the hanger 1. See
In some embodiments of the invention, after the joist hanger 1 has been attached to the header 3, the top flanges 43 can be bent away from the top surface 42 of the header 3 so that no portion of the hanger 1 extends above the top surface 42 of the header 3. The top flanges 43 could be bent back with a screw driver or pliers, or even removed. If this is done, the top surface 42 of the header 3 is uncovered, presenting a completely flat surface for the installation of the sub-flooring 46 or other spanning members. The inventors realize that installers are usually time pressured and may not take the time to bend the top flanges 43 back.
Notches 52 as shown in
In the preferred embodiment, the back flanges 38 are formed with triangle-shaped openings 53 to indicate that extra fasteners may be added where additional loading of the joist hanger 1 is expected.
In the preferred embodiment, at the tops of the side walls 11 and 12 of the joist hanger 1, upper bend tabs 54 are formed that help guide the I-Joist 2 between the side walls 11 and 12. The upper tabs 54 at the tops of the side walls 11 and 12 flare outwardly to form a funnel for receiving the bottom 5 of the I-Joist 2.
In the preferred form, notches 55 are made between the bend tabs 54 and the back flanges 38 and portions of the side walls 11 and 12 and the back flanges 38 to allow the bend tabs 54 to more easily give, making it easier to initially slip the I-Joist 2 into the joist hanger 1 at a skewed angle.
In the preferred form of the invention, the seat 4 of the joist hanger 1 is 2 inches deep to provide an appropriate bearing surface for a typical light-frame I-Joist 2.
Preferably, the joist hanger 1 is constructed in a manner that allows it to be produced from a single strip of light gauge sheet metal bent and embossed at appropriate locations to form the completed joist hanger 1. This process is preferably accomplished on an automated, progressive die.
Preferably, the joist hangers 1 are die-formed from No. 18 gauge galvanized steel. The galvanizing and steel comply with ASTM A 653-97, G 60 specification or better. The steel has a minimum yield strength of 28,000 psi or better and a minimum tensile strength of 38,000 psi or better.
In use, the joist hanger 1 is mounted on the header 3 by appropriate fasteners 40. In light frame wood construction this would generally be nails 40 driven through openings 41 provided in the back flanges 38 for attaching the joist hanger 1 to the header 3. Thereafter, the I-Joist 2 is simply pressed into place onto the seat 4 and between the side walls 11 and 12 and the guides 17 and 18 on the side walls 11 and 12.
If the joist 32 is made from solid-sawn lumber, it will generally need to be further fastened to the joist hanger 1 for resisting uplift forces by appropriate fasteners 35. Again, in light frame wood construction, these would generally be nails 35 or screws. Again, openings 34 would generally be provided in the guides 17 and 18 to make this attachment more easily.
In the preferred embodiment, the joist hanger 1 is used to secure an I-Joist 2 to a solid-sawn wood header 3. The joist hanger 1 is first positioned on the header 3 by selecting where along the header 3 the I-Joist 2 is to be set and then hooking the top flanges 43 of the joist hanger 1 onto the top surface 42 of the header 3. The nail prongs 51 are then driven into the front surface 39 of the header 3. Nails 40 are then driven through openings 41 provided in the back flanges 38 of the joist hanger 1 and into the header 3.
Thereafter, the I-Joist 2 is pressed onto the seat 4. As the bottom chord 7 of the I-Joist 2 passes by the guides 17 and 18 in the side walls 11 and 12, the side walls 10 of the bottom chord 7 push on the guides 17 and 18, and the guides 17 and 18 push the side walls 11 and 12 outward, allowing passage of the bottom chord 7. When the upper surface 9 of the bottom chord 7 passes by the points 24 on the guides 17 and 18 where they extend inwardly the farthest, the side walls 11 and 12 of the hanger 1 spring back inwardly toward each other. The points 24 of the guides 17 and 18 push on the top surface 9 and the edge between the top surface 9 and side walls 10 of the bottom chord 7, which in turn pushes the bottom surface 5 of the bottom chord 7 onto the seat 4 and the upward projection 31 of the seat 4. This spring-action has led the inventors to refer to the joist hanger 1 as a snap-in hanger. The connection of the I-joist 2 to the joist hanger 1 is then complete. Sub-flooring 46 or other materials to finish the floor diaphragm are then added.
During the making of the preferred connection of the present invention no nails are driven into the I-Joist 2.
Preferably, the joist hanger 1 is attached to the header 3 with 10d common nails.
The joist hangers 1 are preferably intended for use in conjunction with I-Joists 2. The I-Joist 2 is preferably made with either laminated veneer lumber top and bottom chords, dimension lumber flanges or laminated strand lumber top and bottom chords.
The preferred I-Joists 2 manufactured by Trust Joist MacMillan Corporation, include model numbers TJI®/Pro™ 150, 250, 350, representing different sizes. The dimensions of the joist hanger 1 are modified to accommodate each different model of I-Joist listed above.
The header 3 is preferably made from Douglas Fir-Larch or Southern Pine lumber or structural composite lumber.
The preferred form of the present invention has been described in terms of a standard joist hanger 1 wherein the seat 4 lies at what is substantially a right angle to the front surface 39 of the header 3, and the side walls 11 and 12 also lie orthogonally to both the seat 4 and the front surface 39 of the header 3. However, the formations of the present invention have application also in slope and skew hangers.
The most preferred embodiment of the blank 64 of the present invention are shown in
The pair of diagonally offset tabs 65 provide additional restraint against upward forces.
All four sizes of the most preferred embodiment include a pair of strengthening embossments 36 that traverse the seat 4 from the first opposed side wall 11 to the second opposed side wall 12, both continuing farther up the side walls 11 and 12 than the guides 17 and 18. The embossment 36 closer to the back flange 38 is preferably longer than the other embossment 36, and is preferably straight, while the other embossment 36 is shorter and preferably angled in the side walls 11 and 12. The embossments 36 are preferably embossed down 1 times the metal thickness. In all four of the most preferred embodiments, the first and second opposed side walls 11 and 12 are preferably bent up at 90 degrees from the seat 4, and the back flanges 38 are bent down at 90 degrees from the side walls 11 and 12. In all four of the most preferred embodiments, there is an additional pair of strengthening embossments 66 that run from the side walls 11 and 12 into each of the top flanges 43. These embossments 66 are preferably embossed down 0.75 times the metal thickness. Finally, in all four of the most preferred embodiments, the upper bend tabs 54 for funneling the joist 2 are bent down 30 degrees from the side walls 11 and 12. Bend lines are shown broken.
In the largest size of the most preferred embodiment, the seat 4 is preferably 2.4375 inches from the first opposed side wall 11 of the joist hanger 1 to the second opposed side wall 12 of the joist hanger; the first and second opposed side walls 11 and 12 are preferably 15.9688 inches from the seat 4 to the top flanges 43 of the hanger 1; and the top flanges 43, the first and second opposed side walls 11 and 12, and the seat 4 preferably total 37.25 inches. The inwardly projecting guides 17 and 18 are preferably 1.5938 inches from the seat 4.
In the next largest size of the most preferred embodiment, the seat 4 is preferably 3.625 inches from the first opposed side wall 11 of the joist hanger 1 to the second opposed side wall 12 of the joist hanger; the first and second opposed side walls 11 and 12 are preferably 13.9688 inches from the seat 4 to the top flanges 43 of the hanger 1; and the top flanges 43, the first and second opposed side walls 11 and 12, and the seat 4 preferably total 34.4375 inches. The inwardly projecting guides 17 and 18 are preferably 1.5938 inches from the seat 4.
In the third largest size of the most preferred embodiment, the seat 4 is preferably 2.4375 inches from the first opposed side wall 11 of the joist hanger 1 to the second opposed side wall 12 of the joist hanger; the first and second opposed side walls 11 and 12 are preferably 11.8438 inches from the seat 4 to the top flanges 43 of the hanger 1; and the top flanges 43, the first and second opposed side walls 11 and 12, and the seat 4 preferably total 29 inches. The inwardly projecting guides 17 and 18 are preferably 1.5938 inches from the seat 4.
Finally, in the form shown in