Is it true that fire doors are restricted in size?

Yes – fire doors are restricted in size, and for good reason. Their fire performance is only guaranteed if installed within the exact dimensions tested and certified by the manufacturer.

Why Size Matters

Fire doors are tested under strict conditions, and the fire rating (e.g., 30, 60, 90 minutes) only applies to the specific sizes used during testing. Using a door outside of these approved sizes risks non-compliance and failure in a fire.

Testing, Certification & Compliance

Only doors installed to the tested size and configuration are compliant. Councils and certifiers require documentation proving the door matches its approved fire rating. Incorrect sizing may lead to failed inspections or costly replacements.

Safety Comes First

Beyond the paperwork, the real concern is safety. Fire doors are a critical part of a building’s passive fire protection system. Using incorrect sizes or assuming “close enough” is good enough could lead to catastrophic failure during a fire, endangering lives and property.

Key Takeaways

  • Fire door sizes must match tested and certified specs.
  • Check manufacturer documentation before ordering or installing.
  • Incorrect sizes can lead to compliance issues and safety risks.

Stick to the specs—fire safety depends on it.

 

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