by Jerry Peck - Codeman on Wed Nov 04, 2009 8:18 pm
Brent,
That would be based on things other than code.
Here are two examples:
1) Presuming the "fire caulking" is being used to seal penetrations in a non-fire resistance rated assembly such as is used for separation between a dwelling unit and its private garage under the IRC, in which case the intent is not to create a UL fire stop design as would be used for a fire-resistance rated assembly but is simply "to resist the free passage of flame and products of combustion" (wording from the 2006 IRC, R309.1.2) - as long as the two different materials (brands) are not "mixed together" into a "new mixture", there should be nothing wrong with sealing a hole half way around with one brand, running out, then using another brand to finish sealing the rest of the way around. This is because you are not dealing with an approved UL fire-resistive rated firestopping design.
2) Presuming the "fire caulking" is being used as part of UL fire-resistive rated firestopping design in a UL design fire-resistive rated assembly, in which case no, you would not be allowed to start with one brand and finish with another brand as the UL design is manufacturer specific and provided by each manufacturer. Use two separate brands and you are not following the UL design provided by either manufacturer. Firestopping UL designs are very specific for fire-resistive rated assemblies.
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired