What are the fire door and self-closing hardware requirements between a basement suite and the attached garage in a New Brunswick home?

Fire-rated doors and self-closing hardware are mandatory between basement suites and attached garages in New Brunswick to prevent carbon monoxide poisoning and fire spread. The NB Building Code requires a minimum 20-minute fire-rated door with self-closing hinges and proper sealing.

Fire Door Requirements
The door separating any basement living space from an attached garage must have a 20-minute fire rating minimum. This means the door assembly (door, frame, and hardware) can withstand fire exposure for 20 minutes before failing. The door must be solid core construction — typically steel-clad or solid wood with fire-rated core materials. Hollow core doors are not acceptable and will fail inspection.

The door frame must also be fire-rated and properly installed with fire-rated caulking around the perimeter. Any gaps larger than 3mm must be sealed with approved fire-stopping materials. The threshold must create a tight seal when the door is closed.

Self-Closing Hardware
Self-closing hinges or a door closer mechanism is mandatory — the door must automatically return to the closed and latched position from any open angle. This prevents the door from being accidentally left open, which would allow carbon monoxide from vehicle exhaust to enter the living space. Spring-loaded hinges are the most common solution for residential applications, though hydraulic door closers work as well.

Additional Safety Requirements
The door must swing into the garage (away from the living space) to prevent fire or smoke from pushing the door open into the basement suite. A carbon monoxide detector is required within 5 meters of the door on the basement side — this is critical because even properly sealed doors can develop gaps over time.

NB Climate Considerations
Maritime humidity can cause wooden fire doors to swell and warp, preventing proper closure. Steel doors with magnetic weather stripping perform better in NB's climate. The self-closing mechanism must be adjusted seasonally — humidity changes affect door weight and closing force. Test the door monthly to ensure it fully closes and latches automatically.

Installation and Inspection
This work requires a building permit and inspection in New Brunswick. The fire door assembly must be installed by someone familiar with fire-rated construction — improper installation voids the fire rating. The building inspector will verify the door rating, proper installation, self-closing operation, and carbon monoxide detector placement.

Common Mistakes
Never use a standard interior door for this application — it must be fire-rated. Don't install the hinges backwards or use non-fire-rated hardware. Avoid weather stripping that prevents the door from closing completely. The door must latch securely — magnetic catches are not sufficient.

Need help finding a contractor familiar with fire door installation? New Brunswick Basements can match you with basement renovation professionals who understand these critical safety requirements.