Fire Doors: Repair or Replace?
- Feb 16
- 5 min read
A common problem building owners face is defective or damaged fire doors in their buildings, which are now increasingly being identified during annual IQP inspections or BWOF audits. While basic adjustments to fire doors are possible, in some relatively simple situations, the typical response from manufacturers, fire engineers and Councils is that the whole doorset must be replaced. This can cost building owners tens or even hundreds of thousands of dollars when multiple doors must be replaced.
So we asked ourselves: Surely there's a better way?
This is the last topic in our three-part series, where we have discussed the problems with Fire Door tags and common defects in fire doors.
Our intention with this post is not to claim that full replacement is necessarily wrong, but to provide a better understanding of why this course of action is commonly taken and to open the discussion to a more reasonable approach that could save millions for the industry without reducing the building's life safety.
Fire door repair: Is it possible?
Damage to fire doors may result from normal wear and tear or from modifications made by a building occupant or contractor (e.g., adding hardware to the door - often related to security requirements).
While there are NO allowances in NZS 4520 for undertaking repairs or replacing a single part of a door, clause 4.2 refers to AS1530.4 for permitted variations to a fire-rated doorset without a formal assessment, which could be utilised.
For example, an additional surface-mounted self-latching lockset for security is acceptable in residential occupancies when it meets the conditions of AS1530.4:2014 clause 7.9.7:
This clause also limits the diameter of the hole drilled through the door leaf to Ø32mm and the connecting bar to Ø15mm.
The cylinder assembly is to be fixed to the door leaf by steel screws through a steel mounting plate
This clause also allows variations to hardware, including:
reduction of push-plate, metallic plate for a hold-open device, or kickplate;
Alternative closers from the same manufacturer under certain conditions;
variation to the location of the latchset or door set up to 80mm vertically
changes to the latchset or lockset that do not require modification to the door leaf or door frame
However, the problem usually starts when the fire door hardware is removed, leaving the door slightly damaged (e.g., with holes but sometimes no further damage). The main problem is that the standard does not provide a solution, and, by interpreting clause 7.9.2 of AS1530.4, one may conclude that the only "Standard solution" is to replace the entire doorset.
So, that's it? There are no other options? Let's see:
When the fire door is properly identified:
For this first analysis, we start by confirming that it is a fire door and identifying the manufacturer. More detail on identifying the fire door is presented in our first post in this series about fire door tags.
Proposed solution: As the manufacturer is known and the fire door serial number can be obtained, the best approach is to contact the manufacturer and request the fire door model.
The manufacturer can also provide a list of approved hardware for the fire door.
With this information at hand, the easiest solution is to reinstall/replace the hardware with approved hardware.
Alternatively, for the hole created, it may be possible to install an additional approved lockset if the hole is up to Ø32mm, as per clause 7.9.7 of AS1530.
When the fire door cannot be confirmed:
Unfortunately, if the fire door manufacturer is not identified, there are no compliant solutions or best practices to apply at the moment, and the door must be replaced.
Note: This problem is likely affecting all fire doors installed prior to 1988, many of which were installed up to 1997, and possibly a number of newer fire doors.
However, there are some other possible solutions that could be considered.
For example, if it is likely that a large number of identical fire doors need to be replaced in a building because their fire resistance rating cannot be confirmed, it may be more economical to pay for a full fire test (starting at approximately $25,000) to confirm that an exemplar fire door (removed from the building) meets the required fire resistance rating.
While this would require replacing at least 1 fire door (which may cost around $7,000), if it succeeds, all other doors may not need to be replaced. A proper assessment of the door by a suitably qualified professional (i.e. a Chartered Engineer) is required, as in some cases it may be required to upgrade the door (installing smoke seals and intumescent strips) before the test.
This would mean that all other doors would require the same modifications to be compliant.
While this approach would solve the problem of a single building, achieving a generic solution for all noncompliant buildings (and there are many) would require an industry-wide movement to develop a safe, best-practice guideline.
Fire door repair: Are there alternative approaches?
The following question is: What about holes that are larger than Ø32mm or additional damage caused to the door leaf or door frame that cannot be retrofitted in a compliant manner?
Our first thoughts were: "If holes in a firewall can be rectified with tested solutions, why not holes in a fire door? Isn't that just a different substrate? Do we need to replace the door?"
Let's analyse a possible solution for a Ø50mm hole:
While the current standard doesn't specify it, AS/NZS 1905.1:1997 clause 4.2.3 specifies that any timber used in a doorset may be replaced with timber with equal or greater density.
Now, let's suppose the fire door is repaired with a "plug" of Ø50mm hardwood (same or greater density than the fire door), and this plug is overlapped on both sides with a stainless steel plate fixed as per standard requirements (steel mounting plate). Does it seem like a reasonable solution?
Then, if we submit this solution to the test, could we extrapolate it to all other fire doors with similar construction?
This approach is no different from all passive fire solutions used for service penetrations, where the wall (substrate) achieves a certain rating, and the penetration in isolation also achieves a certain rating. If we can use this approach on a firewall, what's the difference in using it in a fire door leaf?
If that's the approach to be applied, we may also need to run separate full-scale tests (one for each fire door type), with the remaining tests conducted on a pilot-scale furnace. But there is still a cost involved.
Further questions:
Considering the best for society, how far could we go with tested/approved repairs to existing fire doors, given the societal benefits of reduced costs and increased safety?
Can this principle be applied to door frames (i.e., cable penetrations for locking devices)?
What's the maximum size of the hole?
How far can this hole be from the edge of the door leaf/frame?
How many "repairs" in a door are considered acceptable?
Can a normal sturdy door be converted into a fire door (i.e. FRR 30 minutes) by installing new seals?
Nelligan Consulting Engineers has a great Fire Engineering team, including an in-house Chartered Passive fire protection consultant with expertise in Fire Doors and the knowledge to assist you with your project at various stages, ensuring the installation is appropriately specified, compliant, cost-effective, and delivered with minimal delays.
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