Bridging is an integral component of the open-web steel joist system that braces the joists against unanticipated horizontal movement during erection, the placing of construction loads, and to permanently restrain the joist chords from out-of-plane or lateral movement when other means are not present. The purpose of this paper is to provide the Specifying Professional a clear understanding of the Steel Joist Institute’s bridging requirements as given in the Standard Specifications [SJI, 2005 and 2007] In the paper, these three distinct bridging functions will be
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What is joist bridging?
INTRODUCTION Bridging is an integral component of the open-web steel joist system that braces the joists against unanticipated horizontal movement during erection, the placing of construction loads, and to permanently restrain the joist chords from out-of-plane or lateral movement when other means are not present.
What is meant by bridging in construction?
Bridging. The term 'bridging' refers to a brace, or an arrangement of braces, that is fixed between floor or roof joists to keep them in place, prevent joist rotation, and distributing loads over more than one joist. Solid bridging involves joist-depth timber being installed perpendicular to and between the joists.
When are bridging rows required on steel joists?
Where the span of the steel joist is over 100 feet through 144 feet as indicated by the GRAY shading, all rows of bridging are considered ERECTION BRIDGING and must be completely installed. The bridging row(s) must be anchored to prevent lateral movement of the joist (see Section 105).
Can steel bar joists support design load?
Steel bar joists are an engineered product and can only support their required design load if the “system” is designed and installed properly.
What is bridging in steel joists?
Bridging provides lateral restraint either permanently or until other means of restraint are provided. When deck is attached this provides the lateral restraint to the joist top chord. \continuous and anchored at both ends. Limit the magnitude and placement of construction loads.
What is the purpose of bridging joists?
During construction, the bridging keeps joists vertical so they can't twist out of place. After construction, for the life of the house, the bridging helps stiffen and strengthen the joists by tying them together so that some of the load on one transfers to neighboring joists.
What is steel bridging installed with?
Our steel bridging system is installed to joists by (4) #8-1¼” long coarse threaded drywall screws for excellent hold down power.
Are joist bridging required?
According to the IRC, joist blocking is only necessary if your joists have a depth greater than 12”. Therefore, for most houses, you are not required to have blocking or bridging if you have traditional lumber joists that are 2” in thickness and up to 12” in width as long as both ends are fastened properly.
How do you install a bridging metal joist?
1:292:55EZ-X Bridging: The One Piece Floor Bridging Solution! - YouTubeYouTubeStart of suggested clipEnd of suggested clipOr he forgot to install them flip them over put them into the joist. Screw em in and you're doneMoreOr he forgot to install them flip them over put them into the joist. Screw em in and you're done even if you forget or you have an existing building that has floor joists.
How do you bridge between joists?
Nail bridging on all joists Start by making sure the original bridging is tightly fastened; add nails or screws if necessary. Then measure the span of the joists (the distance between walls or beams that support the joists). Divide the span by three and add rows of bridging at both of the one-third points.
Is bridging or blocking better?
We think that metal bridging is much easier to install and accomplishes the same thing as solid blocking. Also, solid blocking seems more likely to cause squeaks because of all the extra joints and nails required for installation.
Do you need blocking between floor joists?
There must be blocking where joists overlap over a center beam and every eight feet for 2×10 and taller joists. A good rule of thumb is to think if the distance between any two rows with blocking is more than eight feet, you must add some more blocking there.
Does blocking strengthen floor joists?
As incremental parts of a building's structure, joists are not easily replaced. You can, however, strengthen the joists by securing another length of wood to the existing joist, called "sistering," or reduce wobbly floors with block inserts between the joists, called "blocking."
Does bridging stiffen a floor?
Bridging, or “X-bracing,” allows joists to share weight. As a footstep falls on one joist, some of the force is transferred to neighboring joists. Even if your joists already have a row of bridging at the center of the span, adding a row on each side of the existing bridging will stiffen the floor.
How do I block between I-joists?
To make the blocks, I cut sections of I-joist 1½ inches smaller than the space between the joists, then nail a scrap of ¾-inch subfloor material to each end of the block [1]. This creates two large nailing fins. Calvin Cutts works from a ladder to install the blocks.
How do you reinforce floor joists?
The best way to strengthen floor joists from underneath is to make a supporting mid-span beam or wall beneath the wobbling joists. Using jack posts or 6×6 posts and 2×10 or 2×8 beams perpendicular to the joists will solve any wobble and ensure your joists never move again.
What is bridging in steel joists?
Bridging is an integral component of the open-web steel joist system that braces the joists against unanticipated horizontal movement during erection, the placing of construction loads, and to permanently restrain the joist chords from out-of-plane or lateral movement when other means are not present. The purpose of this paper is to provide the Specifying Professional a clear understanding of the Steel Joist Institute’s bridging requirements as given in the Standard Specifications [SJI, 2005 and 2007] In the paper, these three distinct bridging functions will be
What are joists in columns called?
Joists located at or near column lines (see Figure 3) are referred to as OSHA Column Joists, tie joists, strut joists or “OC” joists. The current OSHA Safety Standards for Steel Erection, 29 CFR Part 1926 require that, where columns are not framed in at least two directions with solid structural steel members, joists at column lines shall be field bolted and the joist bottom chords must be restrained by a vertical stabilizer plate [OSHA, 2001]. The bearing seats of Column Joists will always be provided with slotted holes so that bolts can be inserted at the time of joist placement. Where constructability does not allow a steel joist to be installed directly at the column, the OSHA Safety Standards state that an alternate means of stabilizing the tie joists shall be installed on both sides near the column.
What is OSHA for steel?
Since 1984, representatives of the steel community have worked with the Department of Labor and the Occupational Safety and Health Administration (OSHA) to establish new rules for the safe erection of structural steel and as part of that rule, safe erection standards for Open Web Steel Joists. As stated in the Federal Register [OSHA, 2001],
