I’ve got a building inspector telling me that I can’t use unfaced fiberglass or mineral wool batts or blankets for draftstop material. The IRC 2006 definition of a draft stop in R202 is “a material, device or other construction installed to restrict the movement of air with in open spaces of concealed areas of building components such as crawl spaces, floor-ceileng assemblies, roof-ceiling assemblies and attics.”
The inspector points to section R502.12.1 Materials [Draftstop] which requires that “draftstopping materials shall not be less than 1/2-inch (12.7 mm) gypsum board, 3/8-inch (9.5 mm) wood structural panels, 3/8-inch (9.5 mm) Type 2-M-W particleboard or other approved materials adequately supported. Draftstopping shall be installed parallel to the floor framing members unless otherwise approved by the building official. The integrity of all draftstops shall be maintained.” He feels that because it doesn’t make mention of fiberglass or rock wool that those materials aren’t approved draftstops(although he’ll accept foam or caulk neither of which are specifically mentioned).
Section R502.13 “Fireblocking required” which is on the same page as the above setion just after it, makes reference to section R602.8 which deals with fireblocking.
In Section R602.8.1.1 Unfaced fiberglass, it states that among other things “When piping, conduit or similar obstructions are enocuntered, the insulation shall be packed tightly around the obstruction.”
If tightly packed fiberglass batt is good enough for fireblocking shouldn’t it also be good enough for draftstopping?
Section R502.12.1 makes reference to “other approved materials adequately supported.” What are these other materials?
How can I submit this question to IRC/IBC officals?
Replies
Unfortunately for you, the IBC won't be able to/won't care to help you in your situation. Each Building Official will interpret the code as he/she sees fit. The operative word here is "interpret". The guys and gals who put the code book together do only that. It is the responsibility of each area Official to make sure that the building projects conform to his/her interpretation of the code. The term "interpretation" and it's definition/application was explained to me by our local B.O. after I had a similar question about point loads. Your B.O. is the boss, and I would hesitate going over his head, becuase you won't get the satisfaction you want, and because he is the guy who gives out C.O.s. Don't poop where you eat! :D
Don't poop where you eat! :DGot it.G2
>If tightly packed fiberglass batt is good enough for fireblocking shouldn't it also be good enough for draftstopping?
Not really. Stopping smoke and stopping fire can be different. FG is not an air barrier.
I just had to deal with a draft stopping question, and made a drawing that showed the appropriate steel joist faced with gypsum with all penetrations sealed with caulk. They accepted that drawing, which considering it was Clark County NV (Las Vegas), is a significant accomplishment, as they are the nit-pickiest place I've yet encountered.
The draftstopping sounds similiar to the law here in Mass for some buildings that require an air infiltration barrier.
Unfaced FG batts will not do the trick. There is no solid continuous surface. The trick is you need a solid continuous surface that wind will not blow through. Caulk or foaming the cracks on the plywood or sheetrock makes it all continuous and seals the air leaks.
Stu
Could he caulk the holes in the FG? <G>
If I indicated that I'm way more of an *ssh*le then I get credit for!I meant he could seal up outer sheathing shell with caulk of weather sealant (first choice) or the inner sheetrock. Stu
It was a joke!
you mean FG is a joke? Sorry to miss the point!
The caulk is used to fill gaps, of course, so I just had this silly image in my head of using caulk to fill the millions of gaps between the fibers in fg to allow it to be used as a draft stop.
It's that time of year again.... I have to get that clear caulk out to winterize my screen door. TIP: only use clear, not the white on the screen holes if you want to see anything!