Is a TEK5 In 22 or 24 Gage Reasonable / Possible?

[BSVBD]

Please see my previous thread, "Fasteners to Round Top Chord of OWSJ"

(How do i link to another thread? I tried the "Help" button, but, did not find applicable instrcutions - Thank you!)

Unless i find a practical solution to anchoring to round top chord OWSJ's, i am considering anchoring to the roof deck.

Research discovered that TEK3 (TEK screws with a #3 drill point and threads at 14 tpi) are only available at limited lengths of 4" max. Since we need to travel through 4" of rigid insulation, I need 6-8" screws to bite into the existing roof deck. The TEK screws at 6-8" length are TEK5 with 28 tpi. There are no load tables that i can find that allow a TEK5 to anchor to a steel gage thinner than 16 gage.

Is there a way to calculate pullout of a 28 tpi in 22 or 24 gage roof deck?

Other suggestions?

Thank you!

 

[JedClampett]

An alternative is to use a Nailable Insulation (Atlas makes it, among others) of the thickness required. The nailable insulation has its own attaching criteria, and attaching the steel deck is just the same as attaching to OSB.

 

[BSVBD]

Jed,

This is an existing roof... The insulation and steel deck are already in place.

I'm inquiring about attaching "to" the steel deck.

 

[j19]

Check out the Ultra-Z fastener from Atlas. Their product data sheet shows that it is available in various drill points with lengths up to 8".

http://www.atlasfasteners.com/images/Ultra-Z-TechData.pdf

 

[KootK]

Are you in a position to know if the existing deck to joist connections can do the job once you successfully connect the new stuff to the deck?

Also, will there be shear coming into the fasteners from the new structure? If so, how will that be dealt with? At the roofing level?

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.