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Re: Joist Modification
- To: <seaint(--nospam--at)seaint.org>
- Subject: Re: Joist Modification
- From: "Richard Fennell @ DSI" <rpfennell(--nospam--at)doingsteel.com>
- Date: Mon, 21 Jul 2003 17:23:45 -0500
Title: Joist Modification
I would try and contact a joist fabricator and
talk with them about it.
Probably any joist manufacturer would be able to
give you some ideas.
----- Original Message -----
Sent: Monday, July 21, 2003 2:54 PM
Subject: Joist Modification
I have encountered a situation where a joist bottom
chord prevents proper head room clearance. The joists (24LH 09 - Bottom of
metal deck ~30' AFF) are in a controlled atmosphere building built in the
60's. A platform was installed to provide a means of egress from the upper
walkways in the building. This platform is partially hung from the roof steel
and supported by the existing columns and the exterior tilt-up wall panels.
Joists span 45 feet and support the roof (EPDM, insul & metal deck). As
fate would have it there is only 6'-0" clear below the joist to the platform
(min required is 6'-8") One suggestion is to weld a beam to the bottom of the
top chord for a distance of 8 feet at the end of the joist. Then cut the
joist bottom chord and attach it via members sloped to tie into the bottom
flange of the beam and the bottom chord of the joist. The webs would also be
modified to attach to the beam.
I have never tried such a modification nor seen one
like this, which leads me to believe that it has rarely (if ever) been done. I
am not enthusiastic about such a modification, but I would like to ask if
anyone has ever designed anything similar or seen such an animal. If so I
would appreciate your input. If anyone has any suggestions for modifying the
end of a joist I would also be interested in hearing them. Thanks for any
advice that you may provide.