Fire Door Ratings
Complete Guide
Last updated:
A fire door rating is the time a complete door assembly (door, frame, hardware and glazing) has withstood standard fire testing under NFPA 252 or UL 10C positive pressure. Typical ratings are 20 minutes for corridors and smoke barriers, 45 minutes for most 1-hour fire barriers, 60 or 90 minutes for 1-hour and 2-hour stair and shaft enclosures, and 3 hours for 3-hour fire walls and barriers. NFPA 80 governs installation and requires fire door assemblies to be inspected at least once a year.
Fire Rating Classifications
The required door rating depends on the type of wall and its fire-resistance rating under Section 716 of the Florida Building Code, and is often lower than the wall rating. Doors in interior exit stairway enclosures may also need a temperature-rise rating. Always confirm requirements with the design professional and the authority having jurisdiction.
20 Minutes
Wall Type
Corridor walls (fire partitions) and 1-hour smoke barriers
Common Applications
Glazing Limit
Fire-protection-rated glazing (D-20 marking) up to the maximum size tested and listed
45 Minutes
Wall Type
Most 1-hour fire barriers and fire partitions
Common Applications
Glazing Limit
Fire-protection-rated glazing (D-H-45 marking) up to the maximum size tested and listed
60 Minutes
Wall Type
1-hour shaft, exit stairway and exit passageway enclosures
Common Applications
Glazing Limit
100 sq in of fire-protection-rated glazing, unless listed fire-resistance-rated glazing is used
90 Minutes
Wall Type
2-hour fire barriers, fire walls, shaft and exit stairway enclosures
Common Applications
Glazing Limit
Typically 100 sq in of fire-protection-rated glazing, unless listed fire-resistance-rated glazing is used
3 Hours
Wall Type
3-hour and 4-hour fire walls and fire barriers
Common Applications
Glazing Limit
Fire-resistance-rated glazing (D-H-W-180) to the maximum size tested; fire-protection-rated glazing only in horizontal exits, up to 100 sq in
Fire Door Assembly Components
A fire door is only as strong as its weakest component. Every part of the assembly must be labeled or listed for fire door use and properly installed.
Fire Door
Must bear a permanent label from an approved testing and listing agency
Fire Frame
Must be labeled with a rating equal to or greater than the door it serves
Hardware
Latches, closers and fire exit hardware must be listed for fire doors; hinges must meet NFPA 80 (steel, ball-bearing) or be listed
Glazing
Must be listed for use in fire doors at the required rating; safety glazing rules also apply
Gasketing
Smoke and draft control gasketing where required, plus any edge seals the door's listing calls for
Fire Door Inspection Checklist
NFPA 80 requires fire door assemblies to be inspected and tested at least annually, with written records. Use this checklist to prepare for inspections or self-audit your facilities.
Annual Inspection Items (NFPA 80)
Planning an installation? See our installation services and the Florida Building Code door guide.
Common Fire Door Violations
Avoid these frequent inspection failures that compromise life safety and result in code violations.
Missing or illegible labels
Consequence:
The rating cannot be verified; the opening may need field inspection and relabeling by the listing agency, or replacement
Prevention:
Keep labels legible and mask them during field painting
Door fails to latch
Consequence:
Must be corrected; swinging fire doors need an active latch to stay closed during a fire
Prevention:
Regular maintenance and hardware adjustment
Unapproved modifications
Consequence:
Changes beyond those NFPA 80 permits can void the listing and require evaluation or replacement
Prevention:
Check with the manufacturer or listing agency (such as Intertek) before modifying a fire door
Excessive clearances
Consequence:
Smoke and fire protection compromised; requires correction
Prevention:
Install and adjust per NFPA 80 and the manufacturer's instructions
Blocked or wedged open
Consequence:
Fire code violation that defeats the purpose of the fire door
Prevention:
Use listed hold-open devices that release on fire alarm or smoke detection
Fire Door Rating FAQs
What fire rating does a commercial door need?
The required rating depends on the wall the door is in. Typical ratings are 20 minutes for corridor walls and smoke barriers, 45 minutes for most 1-hour fire barriers and fire partitions, 60 minutes for 1-hour stair and shaft enclosures, 90 minutes for 2-hour walls and enclosures, and 3 hours for 3-hour and 4-hour fire walls and fire barriers.
How often do fire doors have to be inspected?
NFPA 80 requires fire door assemblies to be inspected and tested at least annually by a person with knowledge of the door's operating components, with written records kept for the authority having jurisdiction. New installations also require acceptance testing.
What is positive pressure fire testing?
Positive pressure testing under NFPA 252 or UL 10C places the furnace's neutral pressure plane no higher than 40 inches above the sill, so heat and flame push through the door edges as they would in a real fire. The Florida Building Code requires it for side-hinged and pivoted swinging fire doors, which is why many assemblies use intumescent edge seals.
What is a temperature-rise fire door?
A temperature-rise door limits the heat transmitted to the unexposed side during the first 30 minutes of the fire test, and its label shows the maximum rise, such as 250°F, 450°F or 650°F. Doors in interior exit stairway and exit passageway enclosures generally need a maximum 450°F rise, except in buildings equipped throughout with automatic sprinklers.
Can a fire door be modified in the field?
Only in limited ways. NFPA 80 permits certain jobsite work, such as holes for surface-applied hardware and installing labeled viewers or protection plates. Other modifications need approval from the manufacturer or listing agency and may require field inspection and relabeling.
Products for Fire-Rated Openings
- Fire-Rated Doors & FramesEvery door and frame we supply with a fire rating, 20 minutes to 3 hours.
- Hollow Metal DoorsSteel doors for heavy-use, fire-rated and hurricane-rated openings.
- Wood DoorsCustom architectural and prehung wood doors, fire-rated to 90 minutes.
- Standard Welded FramesFactory-welded frames fabricated in Orlando for new construction.
- Glass Light Kits & Vision LitesVision lites and light kits factory glazed into hollow metal and wood doors.
- Exit Devices & Panic HardwareRim, vertical rod and mortise devices, including UL listed fire exit hardware.
- Commercial Door ClosersSurface, concealed and floor closers plus low-energy operators.
- Commercial Door HingesBall bearing, continuous, swing clear and power transfer hinges.
Specification, Fabrication and Installation Services
Related Articles
- Door HardwarePemko Fire Door GasketsPemko adhesive fire door gaskets meet Category G and Category H seal requirements to prevent fire and smoke transfer around commercial door assemblies.
- Door FramesThe Role of Hollow Metal Frames in Commercial ConstructionHollow metal frames give commercial doors strength, fire resistance, and security. Learn their benefits, applications, customization, and code requirements.
- Commercial DoorsChoosing the Right Commercial Doors for Schools and Educational FacilitiesSelecting commercial doors for schools means coordinating doors, frames, hardware, fire ratings, accessibility, and security for high-traffic learning spaces.
Need Fire-Rated Doors for Your Project?
Mills & Nebraska provides Intertek certified labeling for fire and wind in-house, and supplies labeled fire doors, frames and listed hardware with documentation for your Florida projects.