Ul y634 Penetration with fastners

Question

Posted by Joseph D Kellyalmost 4 years ago

We have a 2 hour rated structural frame on a three story atrium. We need to attached cables for sway bracing of light fixtures. The only place we can attach the bracing is on an intumescent coated HSS 8x8 beam. We used UL Y634 as the design coating for the beam. Are we able to drill through the coating to install eyebolt's??

intumescent coating,Y634,Fasteners in intumescent

1 Reply

Posted by Perla Salcedoalmost 4 years ago

Hello Joseph, yes you are able to drill through the coating to install the eyebolts since these take up minor space on the HSS. If for any reason when drilling in the eyebolts in the intumescent is damaged, apply more product on the area to restore the required mil thickness. Finally, drilling through the intumescent will not affect the fire performance of Fire Finish 120 .Please let us know if you need more information.

Perla V. Salcedo, MS
Testing and Sales Support Engineer
Hilti North America
Irving Testing and Development Lab: 3701 W. Royal Lane, Suite 100, Irving, TX 75063
E: Perla.Salcedo@hilti.com
W: www.hilti.com

2 comments on this reply

Posted by Perla Salcedoalmost 4 years ago

Joseph, unfortunately there is not language on Y634 that address this. Our approval comes from internal testing. If the inspector were to need more information, please email us at usspeng@hilti.com and we can provide you a letter tailored to your project. Perla V. Salcedo, MS Testing and Sales Support Engineer Hilti North America

Posted by Joseph D Kellyalmost 4 years ago

Hello Perla, Thank you for the quick response. Is there any language in the UL Y634 that I could point to if the Inspector questions the drilling of the HSS beam? I have looked through the Y634 and did not find an general notes. I think it will not be a problem but if I had some back up for the IOR that would be helpful., Thank you again for your assistance,