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Re: Steel Roof Deck Attachment Question

[Subject Prev][Subject Next][Thread Prev][Thread Next] Thanks Stan!

"Caldwell, Stan" wrote:



If you are trying to transfer diaphragm shear forces with fasteners installed through the open web steel joist chord angles from below, the most likely failure mode is tearing of the steel roof deck around the fastener, not shear failure within the fastener itself.  Accordingly, the most important property of the fastener is it's ability to reliably clamp the roof deck to the joist chord.  Pop-rivets only create a small spherical bulb above the deck, and will not clamp it firmly to the joist chord.  For this reason, we are doing our massive repair using fasteners that I like to describe as "industrial strength molly bolts", which have sleeves with collapsing splines.  Two such fasteners are Camcar Textron Fabco FAB-LOK and Gesipa Olympic Bulb-Tite.  Neither of these product lines has ICBO certification, but both have been tested and shown to reliably provide clamping forces in excess of 800 pounds.  The splines in the sleeves collapse into a relatively wide zone that pries against or into the vertical walls of the deck flutes, providing some degree of mechanical interlock in addition to clamping.  For more information, you can refer to my previous posts on this subject, or contact Bob Harding at Western Fastener Companies in Denver at (303)534-0661 or (888)534-0661.

Hope this helps!

Stan Caldwell in Dallas

-----Original Message-----
From: Joseph R. Grill [mailto:jbotch(--nospam--at)]
Sent: Thursday, June 29, 2000 6:05 AM
To: seaint(--nospam--at)
Subject: Re: Steel Roof Deck Attachment Question

I have been watching this thread as I have a project coming up which may
require extensive retrofit in this area.  have you any idea where we can
get information on these fasteners such as manufacturers, suppliers, etc.
Joseph R Grill, PE

"Philip T. Hodge" wrote:

> There is a product used in aviation commonly referred to as cherry
> rivets.  They are installed from one side, similar to a pop rivet, and
> have published shear values.  Can't think of any reason (other than
> cost, perhaps) they wouldn't work here.
> Phil