:| Do you allow friction fiberglass batts as fireblocking per this section? Do they fulfill the requirement to be "installed in suach a manner as to be securely retained in place"? Or do you require solid blocking, or kraft-faced batts?
So is wood. But wood is allowed.Builder Bob said:paper is combustible;hence kinda opposite of "fire" blocking........ .
If it is packed tight into a space and the kraft side is right against another material, then I guess it wouldn't matter. But the kraft facing may not be left exposed (as per instructions on the paper backing). That means exposed even within a cavity IMHO.Darren Emery said:Just curious - why (and per what section of the code) do you require the paper to be removed?
Its surface is exposed to the air. Installed so that another material is against (touching) the paper backing is not exposed (to an airspace).Mac said:If it is in a cavity then why is it exposed?
In the UBC the requirement that the batts be unfaced was worded more clearly, but I think it is still there in R602.8.1. The fact that R602.8.1.1 speaks of unfaced fiberglass implies that that is what is meant in R602.8.1. Beyond that, R602.8.1 list the materials that are allowed. Batts or blankets of mineral or glass fiber are listed. Paper is not listed, therefore it is not allowed.Darren Emery said:Just curious - why (and per what section of the code) do you require the paper to be removed?
Do you require the removal of paper from gypsum board when used as fire blocking too?EPrice said:In the UBC the requirement that the batts be unfaced was worded more clearly, but I think it is still there in R602.8.1. The fact that R602.8.1.1 speaks of unfaced fiberglass implies that that is what is meant in R602.8.1. Beyond that, R602.8.1 list the materials that are allowed. Batts or blankets of mineral or glass fiber are listed. Paper is not listed, therefore it is not allowed.
The paper used to stable it up with will be the first to go, then the batt better be stable on its ownhMac said:Does the full depth & width cavity insulation in an exterior wall cavity count as fireblocking? My point is that the paper doesn't matter - the code allows combustible material to be used as fireblocking. Friction-fitted insulation can come loose and sag or settle, and if concealed in an enclosed stud bay or cavity it willnot be seen, and won't perform its intended funciton. Stapled in place paper face FG has a better probability of staying put.