Building Codes and Inspections/fire doors


I am working on a residential 3 story 3 unit building in
salisbury mass. that has a sprinkler system in it.The
doors are in the inside staircase ways to each unit.
the architect is telling me that we have to use 90 min
doors in 90 steel jambs is this the code,we were going to
use 20 min fire doors does this comply.

Hi Jim -

The Mass State Building Code (8th edition) requires exit enclosures to have a 2-hour fire resistance rating when connecting 4 stories or more (including the basement) and 1 hour when connecting less than 4 stories:

1022.1 Enclosures required. Interior exit stairways and interior exit ramps shall be enclosed with fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 712, or both. Exit enclosures shall have a  fire-resistance rating of not less than 2 hours where connecting four stories or more and not less than 1 hour where connecting less than four stories. The number of stories connected by the exit enclosure shall include any basements but not any mezzanines. Exit enclosures shall have a fire-resistance rating not less than the floor assembly penetrated, but need not exceed 2 hours. Exit enclosures shall lead directly to the exterior of the building or shall be extended to the exterior of the building with an exit passageway conforming to the requirements of Section 1023, except as permitted in Section

According to Table 715.4, a 2-hour exit enclosure requires a 90-minute door, and a 1-hour exit enclosure requires a 1-hour door.  The price difference between 90-minute and 1-hour doors is minimal.

I hope this helps.  Here's a link to the table:

- Lori

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Lori Greene


I can help with code questions related to doors and hardware. I am familiar with the IBC, NFPA 80, NFPA 101, NFPA 105, ADAAG, and ICC/ANSI A117.1. My expertise is specific to door openings.


I have worked in the door and hardware industry since 1986. I have conducted countless presentations on code requirements for doors and hardware, and maintain a blog related to doors and hardware (

Door & Hardware Institute (DHI) Construction Specifications Institute (CSI) National Fire Protection Association (NFPA) International Code Councel (ICC)

Doors & Hardware Magazine

Vermont Technical College, Associate Degree in Architecture and Building Engineering Technology - 1986

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