Sheet LS-130
Fire-Resistance & Assembliesinsight
Matched penetrations and continuity of fire separations
One-line orientation
A rated assembly works only when its openings and joints use the required protection and its construction remains continuous as required by the wall type and listed assembly.
Key points
- Protect every penetration at its code-assigned rating. A 2-hour wall requires every penetration — ducts, pipes, doors, joints — to be protected: firestop and joint systems match the wall (F-rating ≥ 2 hr), while doors and dampers carry their own listed ratings (a 90-minute door, a 1½-hour fire damper). Protecting the whole assembly is the rule.
- Protection methods by penetrant:
- Ducts: rated duct penetrations generally require a fire damper, smoke damper, or combination damper. Use the protection required for that assembly and condition, including any listed exception.
- Pipes / small penetrations: firestopping — rated sealant, collars, putty.
- Doors: rated opening protective (see doors card).
- Wall-to-deck / movement joints: fire-rated caulk + backer rod head-of-wall detail.
- Follow the required termination. When a wall type and listed assembly require deck-to-deck construction, it cannot stop at a dropped ceiling. Other rated walls may terminate at a tested rated ceiling.
- Movement is accommodated, not ignored. Joints use backer rod + fire-rated caulk so the assembly can expand/contract while keeping the barrier intact.
- Weakest-link principle. The labeled rating is a system rating; one unprotected opening drops real performance below the label.
Confusions / comparison
| Penetration / breach | Protect it with | Failure if omitted |
|---|---|---|
| Duct | Fire, smoke, or combination damper as required | Fire or smoke can pass through an unprotected duct |
| Pipe / small opening | Firestopping (sealant, collar, putty) | Open path through the wall |
| Door | Rated opening protective (IBC 716) | Unrated opening defeats wall |
| Wall-to-deck / movement joint | Head-of-wall fire-rated caulk + backer rod | Gap at top of wall |
| Wall termination | Follow the wall type and listed assembly | An incorrect termination breaks the protected construction |
Related
→ Fire-rated walls (this module): the assembly being kept continuous · Fire-rated doors (this module): the door as a protected penetration · Fire-resistance ratings / Table 601 (this module): the required rating the penetrations must match.
Spotted an issue with this card? Tell us →
Related units
Prompt recall the answer, then reveal
Reveal & check —
1 / 5
ratings update your review schedule ·
Round complete