Seismic Restraint of Sprinkler Systems

[Builder Bob]

This questions is geared towards "ye gentlemen of great knowledge and wisdom".

When seismically restraining a sprinkler system in a low rise building using bar joists or trusses for the roofing system, where should the seismic restraint cables or struts be anchored on the bar joist/truss?

Top chord or lower chord?

Would any addition bracing be required for the joist -

i.e. vertically within the joist/truss to tie the chords together;

and/or

bridging to resist overturn?

I have an opinion(from a good ole' country boy's perspective) and would like to see if my opinion is similar to what the scholars of today's society believe.

SDC of D

Cat II or Cat III Seismic Use Group

(Multiple answer may be required based upon the seismic use group)

 

[Builder Bob]

Re: Seismic Restraint of Sprinkler Systems

Here is part of my opinion - top chord. The top chord is designed for compression while the bottom chord is in tensile. (simple truss/bar joist)

Am I on track so far?

 

[mtlogcabin]

Re: Seismic Restraint of Sprinkler Systems

Agree top cord is what the engineers spec. Questioned the attachment to the bottom of a 12"

I-joist floor system. The engineer made them remove them and block in between the I-joist and connect to the blocking

Do you verify they are pre-drilling the anchor holes in the wood as required per anchor manufacture?

 

[Builder Bob]

Re: Seismic Restraint of Sprinkler Systems

Not typically, If we are on a job site, we may spot check an installation if we happen to be there....We tend to let this be covered Chapter 17 inspections.

(PS MTLOG Thanks for the response......Lots of questions little formal training provided at a state or local area in this regard)