Below the ceiling line the rated separation is intact, but in the attic the framers stopped the assembly at the top of the ceiling joists and left the space above open across the unit line. What should the inspector require?
- ANothing, because the attic space above the ceiling line falls outside the required separation
The attic is expressly inside the required separation. The rating is not allowed to stop at the ceiling line.
- BDraftstopping material only, because a rated assembly is not required above a ceiling
Draftstopping limits the spread of fire within concealed spaces and carries no fire-resistance rating. It is not a substitute for continuing a rated assembly.
- CThat the opening be closed with unfaced batt insulation packed tight against the framing
Insulation of any type provides no fire-resistance rating and will not close the assembly. Packing the gap gives the appearance of a seal with none of the performance.
- That the rated separation be continued from the foundation to the underside of the roof sheathing
Why D is correct
A townhouse separation has to be continuous, running from the foundation all the way to the underside of the roof sheathing, with the joint between the wall and the deck closed. An attic that is open over the top of the wall gives fire an unobstructed path from one unit into the next, which defeats the entire separation regardless of how well the wall below was built.
What this question is testing
The item tests whether the candidate understands that a fire-resistance-rated separation must be continuous through concealed spaces, and whether the candidate can distinguish draftstopping from a rated assembly.
On the job
Attics are inspected last, poorly lit, and full of trusses that make sighting down the wall line difficult. This is where separation walls get abandoned, especially where the truss profile changes or a mechanical unit sits over the party wall. Carry a light and walk the full length of the wall on both sides of the unit line. The other frequent finding is a properly built wall with a two-inch gap at the roof deck that nobody thought to close.
Memory technique
Fire goes over the top. A wall that stops at the ceiling is a wall with a door in it.
Exam tip
Follow a rated wall with your finger from the footing to the roof deck. Wherever it stops, that is the answer.
Where to look it up
IRC Chapter 3, Section R302.2 for townhouses, and R302.12 for draftstopping, which is a separate requirement.