Sizing Up Fire Doors and Rated Hardware

Sept. 1, 2006
It's the responsibility of locksmiths to understand all components of steel fire doors. All hardware mounted to fire doors must be properly rated.

When locksmiths are involved with new construction, door and locking hardware is specified by knowledgeable sources such as: architects, architectural hardware consults, or other agents of the architect. Most of the time, the proper hardware has been specified for the fire rated openings.

It's the responsibility of locksmiths to understand all components of steel fire doors. All hardware mounted to fire doors must be properly rated.

When in doubt, the locksmith should always consult available resources from the Steel Door Institute, the door manufacturer and the local authority having jurisdiction (LAHJ). Never degrade fire protection integrity.

The majority of retrofit and installation requests do not involve new construction; and usually are ordered by customers responding to LAHJ inspections or other complaints.

While the customer is always king, it is important to note that in these instances, the customer may not always be right. Customers are not knowledgeable sources, especially in regards to fire rated openings and the fire door hardware callouts, which can often misinterpret the LAHJ requests.

Regarding orders motivated by non-inspection complaints, the customer may be reacting from outside sources, remarks by employees, associates, and/or patrons.

For instance, a complaint to a facility manager might be that doors are being opened too quickly and persons are being hurt by flying doors. A suggestion is made to install window lites and the locksmith is called out to do so.

This is when it is extremely important that the locksmith has a full understanding of the proper hardware that can be mounted onto doors and frames in fire rated openings.

It is tough when the locksmith has to say no to the customer when requests are in conflict with code. The alternative requires the locksmith to accept liability if cited or if catastrophe occurs.

In the case of window lites, there may be alternatives such as wire and glass lite assemblies, smaller and less aesthetic than the customer requests but accommodate the code(s).

Fire Rated Doors

Besides serving as regular doors, fire rated doors must also provide egress during the fire, keep the fire from spreading, and protect people and property. Fire rated doors are available in a variety of materials including wood and metal. Metal fire rated doors can have a much higher fire rating than a wood door.

The fire protection rating of fire rated doors is for the most part relative to the rating of the wall onto which it is mounted. In most case the doors will be 75 percent of the fire protection of the wall.

The hardware mounted to these types of doors must be equally (or better) rated. For this reason locksmiths must know how to recognize a fire rated opening and the rating of the door in order to provide proper hardware with similar ratings.

Fire Door Labels

Every fire-rated door leaves the factory with a fire label securely attached to the door. The fire rated door label must indicate the time (hours or minutes) rating and either: the latch throw for single-point locks; or a notation: "Fire door to be equipped with fire hardware". Labels may indicate the temperature rise.

Fire door labels are made from metal or mylar. The fire protection rating of the door is imprinted on the door label along with a serialized number. The fire protection rating is specified in time (hours or minutes) and may be followed by an industry standard letter classification.

Door labels are not to be removed or painted over. Only a factory or UL representative may remove or apply a door label. However, remember that painters do not know this regulation.

The door label shown in Figure 1 also includes a specification relating to the minimum latch throw that is needed to match the fire protection of the door.

The label is the only means to validate the rating of the door. When missing or obscured, the rating may not be able to be validated.

Frames may be affixed with a frame fire label.

Frames may be separately purchased from doors but must be rated to the level of the door or wall.

The Relationship Of Walls And Doors

Doors are classified and rated by the amount of fire protection they provide.

The fire rating of the door is dependent on the rating of the wall on which the door and frame are mounted. The fire rating of the wall is determined by its location and how it serves the building.

Walls that separate buildings or divide large buildings into segmented and separate fire areas are rated at four hours and fire doors mounted on these walls are rated at three hours.

Walls that protect stairwells, refuges, or vertical enclosures in a building are rated for two hours and doors mounted to these walls are rated for 1-1/2 hours of fire protection.

The walls to boiler rooms and exterior walls where fire exposure is high are rated for two hours. The doors mounted to these types of walls are rated for 1-1/2 hours.

Walls between rooms are usually rated for one hour and so are the doors mounted to them.

Corridor and room partitions must have walls rated for one hour and doors rate at 45 minutes (3/4 hour).

Where fire exposure to an exterior wall is moderate, the wall rating can be one hour and the doors rating 45 minutes.

Openings between living quarters and corridors fire exposure are moderate where smoke and draft control is the primary concern. Codes generally require walls rated for one hour and doors rated for 20 minutes (1/3 hour).

Figure 2 provides a general idea of how the fire opening should be rated. It should not be used to determine ratings rather to spot when a lesser rated door was installed or improper hardware is installed on a fire door.

An example of this is when the locksmith is called out by the customer to replace or repair an exit device. The locksmith recognizes that the exit device is rated for life-safety but not for fire doors.

The locksmith in this circumstance cannot replace it with an exact equivalent. An exit device that is matched with the fire-rating of the door must be retrofitted.

Fire Door Assembly

All components of the door -- frames; locks; hinges; closers; latches; gaskets; lites; glazing materials; and other hardware items -- constitute the fire assembly. For the assembly to be effective, all items must be labeled accordingly.

The locksmith must pay attention when substituting non-rated components as the result will be a loss of fire protection rating in its entirety.

An example of this might occur when retrofitting an exit device to an electric latch-retracting exit equivalent. The existing exit device as well as the electric equivalent might be equally labeled, but a change of hinge could corrupt the entire rating of the assembly.

Many concealed electric hinges are UL rated for applications where low-voltage current is to be carried through the hinge but may not be necessarily be rated for use on fire rated opening.

As components to the fire door assembly, all hinges must be fire-rated. The retrofit of one non-rate (electric) hinge voids the fire-protection rating.

A locksmith might be called out to replace a non-rated electric hinge with a rated concealed electric power transfer (EPT) recommended by the manufacturer of the existing exit device. This creates another problem as cutting out the frame for the EPT will most likely void the fire protection of the frame.

In this case the proper retrofit requires the frame be changed and a frame specified for the rating of the door and EPT cut out.

Another alternative is to carry the voltage across the door and frame by using a surface-mounted power transfer. These devices are not as aesthetic as a concealed transfer but they do not degrade the integrity of fire protection. Remember: Before making any modification to a fire rated opening, contact the authority having jurisdiction.

Fire-Rated Hardware Locations

The location of fire-rated hardware on the door is strictly controlled. All manufacturers of steel fire doors follow the standards of the Steel Door Institute (SDI). This is an organization that reconciles and keeps track of all statutes and standards and is provided as an aid to architects and manufacturers regarding steel doors. The manufacturers of fire-rated hardware also adhere to SDI guidelines.

In this manner, everyone is on the same page. Sometimes an expert locksmith finds more efficient methods to install fire-rated hardware on steel doors. The locksmith wonders why these methods are not shown in the installation instructions. Where it might seem the manufacturer is missing something, it is important to understand that the manufacturer deliberately guides the installation process in steps that might seem redundant but guarantee (as much as possible) that the hardware will be installed properly.

Hardware Reinforcements

One requirement when ordering fire rated doors is to specify the type of hardware that will be mounted on the door. The manufacturer can then reinforce the door in precise areas so that hardware can be adequately fastened. Figure 6 identifies the different reinforcement thicknesses that the manufacturer installs inside their doors.

While installing hardware, if a locksmith sees that there is no internal reinforcement for the fasteners, the locksmith should know the door may not have been intended to support that hardware.

I had a personal experience where a facility manager at a relatively new shopping mall asked me to look at the mall doors as exit devices were always falling of the doors. Even when rivet nuts were used, the exit device would eventually fall off.

I examined the exterior doors and found that all doors either had no labels or had the labels removed. Without the label, the rating could not be validated. I noticed the doors seemed light in weight and seem to flex too much when I deliberately applied force on the top of the door while lodging the door with my foot at the bottom. Using a dial caliper, I measured the thickness of the door skin and found it to be too thin for any type of fire-rated door.

I examined the stripped-out fastener locations and arrived at the determination that the hardware was falling off the doors because the wrong types of doors were installed.

I researched the existing Division 8 specifications and found 18-gauge doors were called for and 20-gauge doors were installed. The records reviewed who was responsible for providing the doors and that person was contacted. The facility manager was delighted when the contractor (when caught) agreed to replace all the doors for free.

This example highlights the need to understand the relationship of doors and hardware.

Glaring Problems

While researching this article, a question I asked door manufacturer resources is what if any points they would like to convey to installers of hardware on steel fire doors. The glaring problems that were commonly cited were:

Fire protection is often degraded when door props are installed. Under no condition should door props be installed on fire rated doors. Especially in office complexes over years of occupation, door props proliferate.

Door closers are mounted improperly. Sometimes door closers are improperly installed on the outside of a door where it can't be protected during a fire. The arms of door closers are improperly installed so the door cannot latch correctly.

Add-on surface mounted hinges are not the answer. When hinge straps break or fail, it is due to door abuse or corrosion issues. Both need to be directly addresses versus slapping on a non-rated hinge support (as in Figure 9).