Exit Capacity

In projects of Type II, III, IV or V construction, architects are often forced to balance the allowable area limits of lesser construction types and the added cost of higher construction types. A fire wall is an ideal solution, as it allows for the cost savings of a lower construction type while allowing the structure on either side of the fire wall to be considered independently from an allowable area standpoint.

On several recent projects, I have seen plan reviewers treat any door opening in the fire wall as a horizontal exit, even if that was not the design team’s intention. The reviewers then issued review comments regarding compliance with the horizontal exit code requirements. This has led me to the question: is an opening in a fire wall automatically a horizontal exit?

Before I get to my answer, you might be asking: why does this matter?

Horizontal exits come with several code requirements, but in the recent projects I mentioned, the plan reviewers were citing the following:

Exit Capacity

Per IBC 1026.1, a horizontal exit can provide up to one half of the total number of exits, total exit width and total egress capacity. So if the door in the fire wall is a horizontal exit, then it can not be providing more than half of the required number of exits or required exit width.If you have a single door in the fire wall and then an exit stair on either side, this is no problem. But once you have multiple doors in the fire wall, the horizontal exit can easily exceed one half of the total required exits/width.

Refuge Areas

Per IBC 1026.4, when a horizontal exit approach is used, a refuge area is required in the space on the other side of the horizontal exit. This refuge area must be large enough to accommodate the original occupant load of the space plus 3 square feet for each occupant entering into the refuge area from the horizontal exit.

Depending on the building arrangement and capacity, providing this refuge area may be a design challenge.

Standpipe Hose Connections

Per IBC 905.4.2, a standpipe hose connection is required on each side of a horizontal exit. An exception does exist if the floor areas adjacent to the horizontal exit are within 130’ of standpipe hose connection with an exit stair.

So if any door in a fire wall is a horizontal exit, each of these code requirements must be met, adding additional cost and design coordination.

Coming back to the original question:

Is an opening in a fire wall automatically a horizontal exit?

I believe the answer is no. A door opening in a fire wall can be a horizontal exit, but it is not required to be a horizonal exit.

My opinion is based on a few factors.

First, let’s look at the definition of fire wall (IBC Chapter 2):

A fire-resistance-rated wall having protected openings, which restricts the spread of fire and extends continuously from the foundation to or through the roof, with sufficient structural stability under fire conditions to allow collapse of construction on either side without collapse of the wall.”

This definition does mention or describe a horizontal exit at all.

Similarly, we can go to IBC Chapter 5, where the general requirements for building height and area are given. Per IBC 503.1:

For the purposes of determining area limitations, height limitations and type of construction, each portion of a building separated by one or more fire walls complying with Section 706 shall be considered to be a separate building.”

This statement indicates that a fire wall creates separate buildings for the purposes of allowable height/area and construction type, but again, it does not mention or describe a horizontal exit.

Finally, if we return to the horizontal exit section of IBC Chapter 10, we see in Section 1026.2 that a horizontal exit is permitted to be provided as either a fire wall or a fire barrier. No where in this section is a fire wall required; it is just given as one of two options. I have never heard of any AHJ requiring all fire barriers to be a horizontal exit, so why would we apply that logic to fire walls?

Icing on the Cake: An ICC Committee Interpretation

I am not the first person to ask this question, and fortunately, the ICC released a committee interpretation on this same issue a few years ago.

To summarize the committee’s interpretation, fire door openings in a fire wall are not required to be considered as a horizontal exit unless the design of the egress system intends to utilize the provisions of a horizontal exit.

Conclusion

While you would think that the code support described above, plus an ICC committee interpretation would be sufficient to persuade any AHJ, I have still experience pushback on this issue from plan reviewers.

Despite this, I believe the intent of the code is to allow a door in a fire wall to be used as a horizontal exit, but not require it. And if the design intention is not to utilize the horizontal exit provisions, then you do not need to be concerned about the exit capacity restrictions, refuge area requirements and additional standpipe hose connections that I described previously.

Have you encountered a similar issue before? If so, please comment below and let me know.

Dryer Exhaust Ducts in Multi-Family Residential Buildings

10/3/2022

I work on a variety of multi-family housing projects, including residential apartment buildings and senior living facilities, where each dwelling unit has its own washer and dryer. In the past, I have always seen the dryer exhaust duct routed through a wall and then into the cavity of a floor-ceiling assembly, but on a recent project, the local AHJ questioned the validity of this approach. This post is a summary of the code requirements and my suggestions for the most straight-forward way to handle the situation. All code references are the 2021 ICC Codes.

Challenge 1: No Dampers Permitted

The first challenge when approaching dryer exhaust ducts is that the International Mechanical Code (IMC) Section 504.2 specifically prohibits the installation of fire dampers or combination fire/smoke dampers.

If your dryer exhaust duct does not penetrate a rated wall or floor assembly, then you likely have no issue. However, since no one wants to look at a dryer exhaust duct running through their apartment, most designers choose to route the duct into the ceiling and then out of the building. This leads us to challenge 2.

Challenge 2: Dampers Required at Floor/Ceiling Penetrations

A duct that penetrates the ceiling of a floor/ceiling assembly and then runs horizontally through the floor cavity and out of the building would be considered a membrane penetration.

IMC Section 607.6.2 requires that duct membrane penetrations of a rated floor/ceiling or roof/ceiling assembly be protected with either a listed ceiling radiation damper or a shaft enclosure (there is a similar requirement in IBC Section 717.6.2).

We already know from our first challenge that a damper is not permitted, so that seemingly leaves a shaft enclosure as the only option. Again, it’s undesirable to building residents or designers to have a shaft enclosure simply to protect a dryer exhaust duct.

Solution

Fortunately, a straight-forward solution is found in IBC 717.6.2.2, Exception 2.

The exception here allows for the omission of a damper at the ceiling membrane penetration when the duct is protected in accordance with IBC Section 714.5.2, is located within the cavity of a wall and does not pass through another dwelling unit or tenant space.

Our situation meets the last two requirements, as the duct is first routed into a wall prior to running through the ceiling cavity, where it then is routed horizontally to the exterior, without passing through another dwelling unit. For the first requirement, IBC Section 714.5.2 states that membrane penetrations of horizontal assemblies must comply with 714.5.1.1 or 714.5.1.2, which give requirements for through-penetration firestop systems. This section also offers 8 different exceptions.

Detail showing the membrane penetration permitted by IBC 717.6.2.2, Exception 2.

Before we get into those exceptions, though, it’s important to point out that running the dryer exhaust duct through a wall and into the ceiling cavity presents us with another code question: how do we address the intersection of the wall and rated floor/ceiling assembly?

If the top of the wall is located completely below the ceiling membrane of the rated floor/ceiling or roof/ceiling assembly, there is no issue. However, this arrangement is difficult to construct, particularly in wood construction, as it would require a continuous ceiling running past the top of the wall.

Most of the time, the top of the wall interrupts the ceiling membrane, meaning the ceiling stops on one side of the wall and continues on the other side. This arrangement would itself be considered a membrane penetration of the floor-ceiling or roof-ceiling assembly, even without a dryer duct present. IBC Section 714.5.2 Exception 7 addresses this exact situation:

The ceiling membrane of a maximum 2-hour fire-resistance-rated horizontal assembly is permitted to be interrupted with the double wood top plate of a wall assembly that is sheathed with Type X gypsum wallboard, provided that all penetrating items through the double top plates are protected in accordance with Section 714.5.1.1 or 714.5.1.2 and the ceiling membrane is tight to the top plates.”

This exception allows for the wall to interrupt the ceiling membrane as long as it is provided with a double wood top-plate that is tight to the ceiling and sheathed with Type X gypsum board. Note that this section does not require the wall to be rated.

Additionally, the exception requires that the duct be protected in accordance with Section 714.5.1.1 or 714.5.1.2 (the same through penetration firestop sections referenced earlier).

For my specific project, the building is a wood-framed structure, so there was no issue in providing a double top plate for each wall. In buildings of Type I or II construction, this would still be a valid approach as long as the wall itself is not a bearing wall and fire-retardant treated wood is used for the double top plate (IBC Section 603.1, Item 1.1).

The final code section here, IBC Section 714.5.1.2, requires an approved through penetration firestop system with F and T ratings of at least 1 hour but not less than the rating of the floor itself. Exception 1 of this section eliminates the requirement for the T rating when the penetration is located within the cavity of a wall.

This requirement forces us to find a listed fire-stop assembly that matches out proposed conditions. There are numerous assemblies available, particularly through companies such as Hilti or 3M.

If you are tracking the code path through the mechanical code, the path is shorter, but the end result is the same. IMC Section 607.6.2, Exception 2 allows for the omission of a damper at the ceiling membrane penetration when the duct is protected in accordance with IBC Section 714.5.1.2, is located within the cavity of a wall and does not pass through another dwelling unit or tenant space. Note the subtle difference in section here compared to IBC Section 717.6.2.2 Exception 2 – the IMC takes you directly to the through penetration firestop requirement.

See the flow chart below comparing the code path through both the IBC and IMC.

Comparison of the IBC and IMC code paths.

Potential Challenge with Firestop System

On the recent project where this issue came up, every firestop assembly for this configuration that I found stated that the dryer duct could be located within a wall, but when the wall was used, it had to be a minimum 1-hour rated wall. This was a challenge because the proposed configuration for my project involved the dryer exhaust duct running through an interior dwelling unit wall which was not rated.

After a few hours of digging through the UL firestop database, I could not find a single listed firestop system that described a duct running through a non-rated wall and then into a 1-hour floor/ceiling assembly. This was a surprising result, as the IBC clearly does not require the wall to be rated when using Section 714.5.2 Exception 7. I ended up pursuing an Engineering Judgment to address the situation.

Conclusion

Both the IBC and IMC provide code paths to route a dryer exhaust duct through wall, into a rated floor/ceiling or roof/ceiling assembly, and then out of the building. A listed firestop assembly is required to address the penetration of the duct through the ceiling membrane. If you happen to be running your duct through a rated wall, there are numerous firestop assemblies readily available for this configuration. If you are running the duct through a non-rated wall, you will likely need an engineering judgement. If you have found a listed firestop assembly that allows for a non-rated wall in this scenario, please let me know!

Which Codes Apply to My Existing Building?

3/30/2022

As I have spent time in existing buildings over the years, whether surveying a building for potential renovations, reviewing existing conditions or doing inspections, the concept of the building “meeting code” often comes up. Building owners, building maintenance staff, or anyone that is concerned with the operation or maintenance of a building wants to know if their building is up to code. Or in some cases, where money for repairs or improvements is hard to come by, they don’t want to know.

Unfortunately, “meeting code” can mean several different things, and it is easy to lose track of which codes actually apply to an existing building.

In this post, we’ll explore the various building and fire codes that could apply to your existing building. There are many other codes (e.g. electrical, elevator) that we won’t specifically address, but the general thought process for those is similar. All references will be to the 2021 ICC codes, but many states and local jurisdictions modify these requirements, so be sure to verify the specific requirements for your area.

Note: If your building is a one or two family dwelling or a townhouse, the International Residential Code (IRC) is likely the applicable code. The IBC and IEBC typically do not apply to such buildings.

Existing Building Scenario 1: Normal Operations

If you have an existing, permitted, occupied building that is proceeding with normal operations (meaning there is no construction activity occurring and you are not changing the use or occupancy of the building from the original design), “meeting code” is fairly simple.

IBC/IEBC Compliance

First, the International Building Code (IBC) and International Existing Building Code (IEBC) generally do not apply to your building. The application of both codes is limited to situations where some level of work is occurring to the building.

For example, IBC 102.3.2 states:

The legal occupancy of any building existing on the date of adoption of this code shall be permitted to continue without change, except as otherwise specifically provided in this code, the International Fire Code or International Property Maintenance Code, or as is deemed necessary by the building official for the general safety and welfare of the occupants and the public.

In other words, the IBC does not require any change to your building unless there is a specific requirement in the International Fire Code (IFC), International Property Maintenance Code (IPMC), or the code official determines there is a required change necessary because of a threat to public safety. We’ll get to the IFC and IPMC shortly, but the final point is an important one to note. The code language does give the Building Code Official the authority to require a change to your building if they deem it is necessary for safety reasons.

In my experience, this authority is typically reserved for use when there is a clear danger to occupant safety. As a hypothetical example: if your building has an exit stairway that does not have any handrails, even though it was permitted that way from the beginning, the code official could deem the lack of handrails a big enough safety risk that they require you to install them. Assuming your building does not have any blatant safety risks, though, it’s unlikely that the code official would use this language to force a change in your building.

Similar to IBC Section 102.3.2, the IEBC has the exact same language in Section 101.4. Additionally, the overall scoping language in IEBC 101.2 states that the provisions of the IEBC apply to the “repair, alteration, change of occupancy, addition to and relocation of existing buildings.” So if you are not performing any of those actions on your building, the IEBC does not apply.

What about NFPA 101?

If you are in a jurisdiction that adopts NFPA 101, there are additional requirements you need to consider.

Unlike the ICC, which separates the IBC and IEBC into two different codes, NFPA 101 applies to both new and existing buildings. For example, NFPA 101 Section 7.1.1 states “Means of egress for both new and existing buildings shall comply with this chapter.” NFPA 101 Chapters 7-11 all apply to both new and existing buildings, so you’ll need to review these chapters for specific existing building requirements that could apply to your situation. After Chapter 11, NFPA 101 contains occupancy-specific chapters that only apply if those occupancies are in your building. These chapters alternate between new and existing occupancies (for example, Chapter 12 applies to new assembly occupancies and Chapter 13 applies to existing assembly occupancies). So the requirements found in any of the applicable “existing” chapters in NFPA 101 would also apply to your building.

IFC Compliance

Second, certain portions of the IFC will apply to your building. The application of the IFC is divided into two categories:

Construction and Design Provisions
Administrative, Operational and Maintenance Provisions

Let’s cover these one at a time:

IFC Construction and Design Requirements

Per IFC Section 102.1, the construction and design provisions of the IFC “apply to:

Structures, facilities and conditions arising after the adoption of this code.
Existing structures, facilities and conditions not legally in existence at the time of adoption of this code.
Existing structures, facilities and conditions where required in Chapter 11.
Existing structures, facilities and conditions that, in the opinion of the fire code official, constitute a distinct hazard to life or property.”

In our Scenario 1 case, Items 1 and 2 would not apply since we are an existing, permitted building.
Items 3 and 4 would apply, though. Item 3 sends us to IFC Chapter 11, and, Item 4, similar to the IBC, gives the code official authority to enforce the IFC on existing buildings if they deem there to be a distinct hazard to life or property.
IFC Chapter 11 primarily focuses on fire safety and means of egress requirements. A few examples include:

Standpipes in buildings with a floor higher than 50 feet
Smoke Alarms in Group R and I occupancies
Guards in the means of egress where the change in level is more than 30 inches
Handrails on at least one side of stairways

These requirements are fairly basic and typically are not difficult to achieve, but this would be a good section to thumb through to determine if they apply to your building. IFC Section 1103.1 details which sections of Chapter 11 apply based on the use and occupancy classifications in your building.

IFC Administrative, Operational and Maintenance Provisions

Per IFC Section 102.2, the administrative, operational and maintenance provisions of the IFC “apply to:

Conditions and operations arising after the adoption of this code.
Existing conditions and operations.”

In our Scenario 1 case, both of these items apply. This means you’ll need to review the IFC chapters that are relevant to the given system or component of your building under consideration to determine if there are any applicable requirements. For example, if you are working with a dry-cleaning facility, there are requirements in IFC Chapter 21 that would apply to how you operate the facility and equipment.

What about NFPA 1?

If you are in a jurisdiction that adopts NFPA 1 in lieu of the IFC, you’ll have a little more work to determine what applies to your building.

Similar to NFPA 101, NFPA 1 applies to both new and existing buildings and contains requirements for existing buildings throughout the code. You’ll need to review the chapters that are relevant to the given system or component of your building under consideration and then find the requirements for existing buildings located within those relevant chapters.

Existing Building Scenario 2: Changing an Existing Building

If you are performing work on your building, there are additional code requirements beyond those described for Scenario 1.

IEBC Compliance

The IEBC is your first stop for determining the applicable code requirements. IEBC Section 101.2 states that the provisions of the IEBC apply to the “repair, alteration, change of occupancy, addition to and relocation of existing buildings.” So you first want to review the definitions of each of these terms in IEBC Chapter 2 and determine which apply to the work you are performing in your building.

For repair work, the requirements of IEBC Chapter 4 apply. The general intent of this chapter is to maintain the existing level of code compliance in the building (at a minimum), though there are some specific additional requirements depending on the system or component undergoing repair.

For relocated building, the requirements of IEBC Chapter 14 apply.

For the other IEBC work classifications: alterations, changes of occupancy and additions, there are three potential compliance paths:

Prescriptive Compliance Method (IEBC Chapter 5)
Work Area Compliance Method (IEBC Chapters 6 through 12)
Performance Compliance Method (IEBC Chapter 13)

Prescriptive Compliance Method

The prescriptive compliance method essentially requires the work being performed to comply with the requirements of the IBC, with a few exceptions involving situations where IBC compliance is unfeasible for an existing building.

For many existing buildings, the requirements of the current edition of the IBC have progressed substantially since the building code that was in effect at the time of original construction, making any attempt to comply with the current IBC requirements difficult.

Work Area Compliance Method

The work area compliance method is the most-commonly used compliance method in the IEBC and generally the most flexible from a technical requirement standpoint. This method applies varying requirements to the work area in the building based on the classification of work that is being performed. When the work area compliance method is used, the scope of work must comply with one or more of the applicable chapters:

Alterations – Level 1 (Chapter 7)
Alterations – Level 2 (Chapter 8)
Alterations – Level 3 (Chapter 9)
Change of Occupancy (Chapter 10)
Additions (Chapter 11)
Historic Buildings (Chapter 12)

For any building alteration, the requirements of Chapter 7 would apply. If the alteration includes “the addition or elimination of any door or window, the reconfiguration or extension of any system, or the installation of any additional equipment,” (IEBC Section 603.1), the requirements of Chapter 8 would also apply for a Level 2 alteration. If the work area exceeds 50% of the building, the requirements of Chapter 9 would also apply for Level 3 alteration.

Changes of occupancy and additions using the work area compliance method must comply with Chapters 10 and 11, respectively.

Finally, if you have a historic building, be sure to reference IEBC Chapter 12 first, as it modifies several the requirements found in Chapters 7-11.

Performance Compliance Method

The performance compliance method involves the evaluation of a variety of building systems and components (including height/area, compartmentation, vertical openings, means of egress, and fire protection systems). These systems are each assigned a score based on the evaluation criteria found in IEBC Chapter 13. These scores are then added to determine a total building score. If the score is high enough for the occupancy classifications involved, the work is deemed to be in compliance with the IEBC.

The performance compliance method is a good option when one aspect of a proposed scope of work cannot conform to the other compliance methods, but the remainder of the building is generally compliant. For example, if an existing building work areas has excessive dead corridor lengths, compliance with the prescriptive compliance method or work area compliance method may be impossible. But the performance compliance method may be a viable option, assuming the building scores well in the other assessment areas.

IBC Compliance

As described above in Scenario 1, compliance with the requirements of the IBC is only required when specifically referenced by the IEBC (or potentially in the IFC and IPMC).

That said, if your work complies with the requirements of the current edition of the IBC adopted in your jurisdiction, this will inherently satisfy the requirements of the IEBC prescriptive compliance method.

What about NFPA 101?

NFPA 101 Chapter 43 applies to any building rehabilitation work, including repairs, renovations, modifications, reconstruction, changes of use/occupancy and additions. Any of these actions would trigger a requirement to comply with NFPA 101 Chapter 43, which then brings in requirements to comply with other portions of NFPA 101, depending on the scope of work.

Generally, NFPA 101 Chapter 43 requires compliance with all requirements found in the applicable existing occupancy chapter (Chapters 13,15,17,19, etc.) plus some additional requirements that vary based on the type of work being performed.

IFC Compliance

As described in Scenario 1, application of the IFC is divided into two categories:

Construction and Design Provisions
Administrative, Operational and Maintenance Provisions

Let’s cover these one at a time:

IFC Construction and Design Requirements

Per IFC Section 102.1, the construction and design provisions of the IFC “apply to:

Structures, facilities and conditions arising after the adoption of this code.
Existing structures, facilities and conditions not legally in existence at the time of adoption of this code.
Existing structures, facilities and conditions where required in Chapter 11.
Existing structures, facilities and conditions that, in the opinion of the fire code official, constitute a distinct hazard to life or property.”

Just as in Scenario 1, Items 3 and 4 would also apply to Scenario 2. Additionally, Item 1 would also apply to the work being performed in the building (since it is creating a new condition). Therefore, any requirement found in the IFC that is applicable to a system or component within the work being performed is applicable. This means you’ll need to review the IFC chapters that are relevant to the given system or component of your building under consideration to determine if there are any applicable requirements.

IFC Administrative, Operational and Maintenance Provisions

Per IFC Section 102.2, the administrative, operational and maintenance provisions of the IFC “apply to:

Conditions and operations arising after the adoption of this code.
Existing conditions and operations.”

Similar to our Scenario 1 case, both of these items apply to Scenario 2.

What about NFPA 1

There are requirements throughout NFPA 1 that would apply to Scenario 2, so again you’ll need review the chapters that are relevant to the given system or component of your building that will be changed and find the requirements for existing buildings within those chapters.

Conclusion

The phrase “meeting code” is used frequently in the A/E/C world but depending on the nature of your building and the work being performed, it can mean many different things!
For an existing building, you likely fall under one of these two scenarios:

Scenario 1: Normal Operation of an Existing Building
Scenario 2: Changes to an Existing Building

Scenario 1 typically requires compliance only with certain portions of the IFC. Scenario 2 requires compliance with the IEBC and the IFC. If you are in a jurisdiction enforcing NFPA 1 and 101, there are also requirements from these codes that apply to both scenarios.

Three Approaches to Mixed Occupancy Buildings

2/18/2022

The IBC offers 3 approaches to mixed occupancy buildings: accessory, nonseparated and separated. Any building with two or more occupancy types must choose one or more of these approaches for compliance. In this post, we will cover all three of these approaches and the specific requirements related to each.

Many urban buildings are mixed occupancy buildings and use one of these described approaches.

Nonseparated Mixed Occupancy

In a nonseparated occupancy approach, there is no requirement for a fire-rated separation between adjacent occupancies. However, the key requirement in a nonseparated occupancy approach is that the most restrictive requirements for the allowable height, area and number of stories, as well as the most restrictive fire protection requirements must be applied throughout the entire building. For example if your building has two occupancy types and one of them requires a voice fire alarm system, a nonseparated occupancy approach would mean that you need to provide a voice fire alarm system throughout the building.

If your building falls within the allowable height and area for the occupancy types involved and you can meet the fire protection requirements of the most restrictive occupancy, a nonseparated mixed occupancy approach is the easiest from a design standpoint because there is no additional requirements for rated separations.

The general approach for code compliance in a non separated mixed occupancy building is:
1. Determine the maximum allowable height, area and number of stories for each occupancy involved and verify that your building meets the most restrictive requirements.
2. Determine the fire protection requirements from IBC Chapter 9 for each occupancy involved and apply the most restrictive requirements throughout the building. If the building is a high-rise, the requiremetns of Section 403 would also apply throughout.
3. Apply all other code requirements, such as means of egress, to each individual occupancy classification individually for that portion of the building.

Note that even if you are taking a nonseparated occupancy approach there are specific requirements for buildings containing Groups H, I and R for a rated separation between those occupancies and adjacent building spaces you can review those requirements in IBC Chapter 4.

Separated Mixed Occupancy

The separated mixed occupancy approach is typically provided when the non-separated approach is not an option. With a separated mixed occupancy approach, a fire-rated separation is typically provided between each occupancy type. IBC Table 508.4 is referenced for the specific rating requirement, though a rated separation may not be required between occupancies of a similar hazard level.

The allowable height and number of stories is applied for each individual occupancy type. For example, if your construction type limits a Group A occupancy to 4 stories, your building could be taller as long as the Group A occupancy is not located above the fourth story.

The allowable area is based on the sum of the ratios of the actual floor area for each occupancy divided by the allowable floor area of that occupancy. The sum of these ratios cannot exceed one for any given story. Requirements for egress and fire protection systems are applied invidivualy to each separated occupancy in the building.

The general approach for code compliance in a separated mixed occupancy building is:

Determine the minimum required fire resistance rating between adjacent occupancies.
Determine the actual area and allowable area for each occupancy involved.
Verify that the sum of the actual to allowable area ratios is not more than 1 for any story and not more than 3 for the entire building (assuming an NFPA 13 sprinkler system).
Verify that the locations of occupancies do not exceed their allowable height or number of stories based on the type of construction.

All other code requirements such as means of egress or fire protection are applied to each individual occupancy where it is located in the building. Note that Chapter 9 may require sprinkler protection throughout the building, even with separated occupancies, so be sure to review the requirements that apply to your specific situation.

Accessory Occupancy

The final option is an accessory occupancy approach. This method is applicable where there is a small portion of a building or space that is subsidiary to the main occupancy. When that smaller space is 10% or less of the total area of a story, an accessory occupancy approach can be used.

There is no required separation between the accessory and main occupancy, and the building height, area and number of stories are based on the main occupancy, not the accessory occupancy. If the building contains a Group H, I or R occupancy, those separation requirements found in Chapter 4 would still apply.

Within the accessory occupancy, other code requirements such as egress and fire protection systems are based on the accessory occupancy classification, not the main occupancy. This is crucial point that confuses many people. Essentially, the accessory occupancy designation allows you to ignore the height, area and number of stories requirements for the accessory occupancy, but all of the other code requirements for the accessory occupancy still apply.

For example, a large conference room located within an office building could be considered an accessory occupancy, so the limitations for height, area and number of stories for Group A-3 occupancies would not apply. But all of the other code requirements for Group A-3, including means of egress and fire protection requirements would still apply!

Bonus: Fire Walls

One final option - if you are able to separate multiple occupancies using a fire wall, you create two separate buildings from a code application standpoint and you can consider each building indvidually. A fire wall is the most robust separation option available though, so its likely to be the most disruptive from a design standpoint.

Conclusion

In summary, there are three approaches to mixed occupancy buildings: non separated, separated and accessory. All buildings with multiple occupancies must use one or more of these approaches. If your building contains three mor more occupancy types, it's possible to use a combination of the approaches, such as designating an accessory occupancy and then taking a nonseparated approach for the remaining occupancies.

Using Frontage to Increase Allowable Building Area

1/21/2022

5 Comments

If you have designed a building of Type II, III, IV or V construction, you probably considered the allowable building area, which depends on the construction type, occupancy classifications, presence of fire sprinkler systems, and a few other criteria.

One common way to increase the allowable area for a building is to use a frontage increase. The frontage increase provision in the IBC, found in Section 506.3, recognizes the safety benefits of having open space directly adjacent to a building. When a fire department or other emergency responders arrive to a site, there is an increased level of effectiveness when those personnel can access a large portion of the building exterior.

A public way, such as a street that is at least 20 feet wide, counts towards the frontage increase.

Using Frontage to Increase Allowable Building Area

There is no requirement for a building to use the frontage increase provisions of IBC Section 506.3, but when used, the following requirements apply:

A minimum of 25% of the building perimeter must be adjacent to a public way or open space
To count as frontage, the open space must be either on the same lot or a dedicated public space. Open space on an adjacent lot does not count.
The width of the open space must be at least 20 feet, measured at right angles from the building exterior wall to: (1) the closest interior lot line, (2) the entire width of the public way, or (3) the exterior face of a building on the same property.
The open space must be accessed from a street or fire lane

Performing the Frontage Calculation

The frontage calculation can be performed by hand, but I recommend the building frontage calculator. If you want to do the calculation on your own, here are the steps. Note that this method is valid through the 2018 IBC. Starting in 2021, the method has changed, which I will cover in a future update.

1. Determine the weighted average of the width of open space (W).

This value, W, is determined by the following equation:

W = (L₁ x W₁ + L₂ x W₂...)/F

Where:
L_n and W_n are the length of wall segment and width of open space adjacent to that wall segment. Remember that W has to be at least 20 feet. If the width of the public way or open space is greater than 30 feet, you are required to use a maximum value of 30 feet for the calculation.

F is total building perimeter fronting a public way or open space with a width of 20 feet or more.

2. Determine the total building perimeter, P.
3. Solve IBC Equation 5-5 to determine the frontage increase factor.

I_f = [F/P - 0.25] W/30

The frontage increase factor can then be used with IBC Equations 5-2 or 5-3 to determine the allowable area the building. In these equations, the frontage increase factor is multipled by the "NS" allowable area value from IBC Chapter 5.

Notice that with Equation 5-5, the maximum possible frontage increase factor is 0.75. In order to achieve this maximum value, the entire building perimeter has to front an open space or public way with width of 30 feet or more. If the width at any point is less than 30 feet, or if a portion of the building perimeter does not have any frontage, the frontage increase factor will be reduced.

You can also directly input the frontage increase factor into the allowable area calculators below:

Link: Separated Mixed Occupancy Area Calculator
Link: Nonseparated Mixed Occupancy Area Calculator

Conclusion

Using the frontage increase provisions of IBC 506.3 is a common way to increase the allowable area of a building. There is no requirement to use these provisions, but when you do, the requirement described above do apply.

When working with architects, I frequently see code summary sheets with a frontage calculation for Type I buildings that have an unlimited allowable area. Since there is no requirement to take a frontage increase, I typically remind architects they don’t need to perform the frontage calculations if the building already has an unlimited allowable area. This saves time and also prevents possible permit review comments on a code provision that wasn’t needed in the first place.

5 Comments

NFPA 285: An Overview

1/7/2022

NFPA 285 is the “Standard Fire Test Method for Evaluation of Fire Propagation Characteristics of Exterior Wall Assemblies Containing Combustible Components.” How’s that for a title? Despite the lengthy name, the goal of the test is quite simple – to understand how fire will spread on an exterior wall. In this article, we’ll briefly review the history of NFPA 285, discuss the criteria for the rest, and then review when compliance with NFPA 285 is required in the IBC.

Many high-rise buildings require NFPA 285-compliant exterior wall assemblies.

NFPA 285 History

The NFPA 285 standard was first published in 1998 and is currently on it’s 4th edition, published in 2019. But the origins of NFPA 285 go all the way back to the 1970s, when foam plastic insulation became a popular choice for energy conservation in (or on) exterior walls. Based on work by the Society of Plastics Industry, the first test for flammability characteristics of an exterior wall was developed. This test was named UBC 17-6 and was first adopted by the Uniform Building Code (UBC) in 1988. This same test was later renamed as UBC 26-4 [1].

UBC 17-6/UBC 26-4 was a massive, full-scale test, consisting of a two-story exterior wall, totaling 24 feet in height (12 feet for each story). The test evaluated both vertical and lateral flame spread on nonload-bearing exterior walls containing foam plastics. Several wall assemblies containing foam plastics passed the test and, starting with the 1988 UBC, could be used as exterior wall assemblies in Type I, II, III and IV construction. A few years later, a modified test, using a smaller scale was adopted as UBC 26-9.

10 years after the first adoption UBC 26-4, NFPA released the first edition of NFPA 285, entitled “Standard Fire Test Method for Evaluation of Fire Propagation Characteristics of Exterior Non-Load-Bearing Wall Assemblies Containing Combustible Components.” This version of NFPA 285, published in 1998, is the same as the UBC 26-9 test.

Notice the difference in the name between the 1998 version of NFPA 285 and the 2019 version. The “nonload-bearing” restriction has been removed, now allowing load-bearing walls to be tested (although the standard itself does not require the application of a live load during testing).

NFPA 285 Test Criteria

The NFPA 285 testing criteria is nuanced, with variations based on the materials used in the wall assembly and the thickness of certain components in the wall assembly. For a full explanation of the acceptance criteria, review Section 10.2 of the 2019 edition of NFPA 285.

Generally, the acceptance criteria involves the following:

Flame propagation on the exterior face of the wall assembly

Vertical flame spread of less than 10 feet above the window opening in the test
Lateral flame spread of less than 5 feet from the centerline of the window opening
Temperature less than 1000 F at a point 10 feet above the window opening

Flame propagation through combustible components and insulation
Depending on the materials used in the exterior wall assembly, there are various temperature requirements that must be met. These include:

Limitations on temperature within exterior wall panels containing combustible components
Limitations on temperature within the air cavity between exterior wall panels and the wall itself

These temperature requirements apply both vertically and laterally and are measured by thermocouples placed above and to the side of the first story window opening.

Temperatures in the second story

The temperature in the second story room cannot rise more than 500 F above the temperature at the start of the test, measured 1-inch from the interior side of the wall assembly

Flame Propagation to second story

Flames cannot spread to the inside of the second story room

Flame propagation to adjacent horizontal spaces

Flames cannot spread horizontally beyond the side walls of the test

When is NFPA 285 Compliance Required?

In the 2021 IBC, there are a number of triggers for NFPA 285 compliance. If you are using an earlier version of the code, the requirements are fairly similar, but refer to the corresponding sections in the applicable code edition for the specific details.

Water Resistive Barriers (IBC 1402.5)
Exterior walls in buildings of Type I, II, III or IV construction that are greater than 40 feet above grade plane must comply with NFPA 285 if they contain a water-resistive barrier. There are two key exceptions:

If the water-resistive-barrier is the only combustible component in the exterior wall and the wall has a brick, concrete, stone, terra cotta, stucco or steel covering meeting the thickness requirements in IBC 1404.2.
If the water-resistive-barrier is the only combustible component and it:
1. Has a peak heat release of less than 150 kW per square meter, a total heat release of less than 20 MJ per square meter and an effective heat of combustion of less than 18MJ/kg when tested per ASTM E1354 with an incident heat flux of 50 kW per square meter.
2. Has a flame spread index of 25 or less and a smoke-developed index of 450 or less as determined by ASTM E84.

For this section, fenestration products, flashing of fenestration and water-resistive-barrier flashing are not considered to be part of the weather-resistive-barrier. If any of these materials are combustible, the exceptions above do not apply.

Metal Composite Materials (MCMs) (IBC 1406.10.3)
Exterior walls containing MCMs in buildings of Type I, II, III or IV construction that are greater than 40 feet above grade plane must comply with NFPA 285. Note that the 2021 IBC has removed several exceptions that existed in previous editions regarding the height of the MCM panels and the area of wall covered by the panels.

High-Pressure Laminates (HPLs) (IBC 1408.10.4)
Exterior walls containing HPLs in buildings of Type I, II, III or IV construction must comply with NFPA 285. There are two key exception for when HPLs are installed 40 feet or less above grade plane:

When the fire separation distance is 5 feet or less and the area of HPLs does not exceed 10% of the exterior wall surface area.
When the fire separation distance is greater than 5 feet. In this case, the area of HPLs is not limited.

Mechanical Equipment Screens (IBC 1511.6.2)
Compliance with NFPA 285 is one of three possible code paths for providing combustible mechanical equipment screens on the roof decks of buildings of Type I, II, III or IV construction.

Foam Plastic Insulation (IBC 2603.5.5)
Exterior walls containing foam plastic insulation in buildings of Type I, II, III or IV construction of any height must comply with NFPA 285. There are several exceptions:

One story buildings where the foam plastic has a flame spread index of 25 or less, smoke-developed index of not more than 450 and is covered by at least 0.032” of aluminum or 0.015” of corrosion-resistant steel and the building is fully sprinkler protected per NFPA 13. This exception only applies to foam plastic insulation with a thickness of 4” or less.
When the foam plastic insulation is covered on each face by minimum 1” of masonry or concrete and one of the following conditions is met:
- No airspace between the insulation and concrete/masonry cover.
- The insulation has a flame spread index of 25 or less per ASTM E84 and the maximum airspace between the insulation and concrete/masonry cover is 1”.

Fireblocking (IBC 718.2.6, Exception 3)
Fireblocking is not required in exterior walls when the exterior wall covering complies with NFPA 285.

Key Items to Know

Wall Assembly vs. Wall Components
NFPA 285 tests wall assemblies as a whole. Individual components of the wall are not considered, rather the entire exterior wall assembly is evaluated for compliance with the standard.

Deviation from NFPA 285 Assemblies
The use of Engineering Judgements (Ejs) for NFPA 285 compliance is a well-debated topic in the design industry. On one hand, it can be impractical to test an exterior wall assembly with every possible variation of material and component (remember that NFPA 285 is a full-scale test of a specific wall assembly). But on the other hand, it can be difficult to judge how variation from a tested assembly will impact performance.

While there are many exterior wall assemblies that have passed the NFPA 285 test, in my experience, many designers choose an assembly that has not been specifically tested. Many manufacturers of exterior wall products will obtain a testing report from ICC Engineering Services (an ICC ES Report, or something similar from another testing agency) that claims the product would pass NFPA 285 if tested. These reports, which essentially amount to a generalized EJ, are typically based on substituting one or more products into a wall assembly that has passed NFPA 285.

If the EJ route is chosen, the EJ should be provided by a qualified design professional, such as a licensed fire protection engineer with experience in the evaluation of exterior wall assemblies.

NFPA 285 vs. ASTM E119
NFPA 285 is different from ASTM E119, the test most commonly used to establish fire-resistance ratings for wall assemblies. This means that if your exterior wall is required to have a fire resistance rating, it also needs to have been tested per ASTM E119. Unfortunately, there are many walls that have a fire-resistance rating per ASTM E119 but do not pass NFPA 285. Similarly, there are walls that comply with NFPA 285 but may not be tested to ASTM E119.

This means that if your exterior wall is required to have a fire resistance rating and comply with NFPA 285, there are at least four potential code paths available:

Provide an exterior wall assembly that has been tested to ASTM E119 for the required fire-resistance rating and has also passed NFPA 285
Provide an exterior wall assembly that achieves the required fire-resistance rating using the prescriptive fire resistance method (IBC 721) or calculated fire resistance method (IBC 722) and has also passed NFPA 285.
Provide a wall that uses an IBC ESR report (or similar) to achieve compliance with one or both of the testing requirements.
Obtain an Engineering Judgement (EJ) to achieve compliance with one or both of the testing requirements.

Note that the acceptance of the last two items will vary by jurisdiction. In my experience, most AHJs are satisfied by an ICC ESR report, but the acceptance of EJs can vary greatly. See the section below for more on Ejs.

Finding NFPA 285 Wall Assemblies
To my knowledge, the best place to find wall assemblies that have been tested to NFPA 285 is the UL database. You can search “FWFO” in the UL directory to find the list, or checkout the database below of all UL-listed assemblies.

As mentioned earlier, many designers use the Engineering Judgement route to demonstrate NFPA 285 compliance. Wall assemblies using this code path are not listed in the above UL database.

Changes to the 2019 Edition
The 2019 edition has been updated with a new title, now allowing for load-bearing walls, but has also been updated with a few key technical changes. A few notable changes:

Wood stud wall assemblies are now permitted in the test
Protection of the window head, jamb and sill are now specifically described in the test (previously there was no requirement on how to detail these areas in the test)
Joint locations – the new test now requires a vertical joint within 1 foot of the center of the window and a horizontal joint between 1 and 3 feet from the window.

It’s crucial to note that the 2019 testing requirements are in many ways more rigorous than past editions. Wall assemblies that have passed earlier editions of NFPA 285 may not comply with the 2019 edition.

Guide to Locking Egress Doors

11/11/2021

In almost every building, owners or tenants have a need for some level of security or access control. The IBC covers a wide range of door locking and control techniques, but the shear number of sections and underlying requirements can be tough to digest. Many folks have trouble knowing which code sections apply, and even if the correct section is identified, it can be a challenge to understand the requirements.

In this post, I take a number of these door locking requirements and translate them into (hopefully) more clear and concise language. I also provide some general commentary on my experience in using each type of door/locking arrangement. References are provided to the last 3 editions of the IBC.

Click one of the door/lock types in table below to jump to that section.

Component	2015 IBC	2018 IBC	2021 IBC
Revolving Doors	1010.1.4.1	1010.1.4.1	1010.3.1
Power-Operated Doors	1010.1.4.2	1010.1.4.2	1010.3.2
Special Purpose Horizontal Sliding, Accordion or Folding Doors	1010.1.4.3	1010.1.4.3	1010.3.3
Educational Occupancies	-	1010.1.4.4	1010.2.8
Security Grilles	1010.1.4.4	1010.1.4.5	101.3.4
Group I-1 and I-2 Controlled Egress	1010.1.9.6	1010.1.9.7	1010.2.14
Delayed Egress	1010.1.9.7	1010.1.9.8	1010.2.13
Sensor Release of Electrically Locked Doors	1010.1.9.8	1010.1.9.9	1010.2.12
Electromagnetically Locked Doors	1010.1.9.9	-	-
Door Hardware Release of Electrically Locked Doors	-	1010.1.9.10	1010.2.11
Correctional Facilities	1010.1.9.10	1010.1.9.11	1010.2.15
Stairway Doors	1010.1.9.11	1010.1.9.12	1010.2.7
Panic and Fire Exit Hardware	1010.1.10	1010.1.10	1010.2.9

Revolving Doors

Many designers don't realize that a revolving door can be used in an egress path, as long as certain requirements are met.

All revolving doors must meet the following requirements, but be sure to check out the paragraph below this one for additional requirements for egress/non-egress doors.

Comply with BHMA A156.27 and the manufacturer's instructions.
Each revolving door must have "breakout" capability per BHMA A156.27 and have an aggregate width of at least 36 inches.
A revolving door must be at least 10 feet from the top or bottom of stairs and escalators. A dispersal area must be provided between the stair/escalator and the revolving doors.
The revolving door speed (in RPMs) cannot exceed the maximum rpm as specified in BHMA A156.27. Manual revolving doors must comply with Table 1010.1.4.1(1). Automatic or power-operated revolving doors shall comply with Table 1010.1.4.1(2).
An emergency stop switch is required near each entry point of power or automatic operated revolving doors within 48 inches of the door and between 24 inches and 48 inches above the floor. The activation area of the emergency stop switch button must be at least 1 inch in diameter and red in color.
Each revolving door must have a side-hinged swinging door that complies with IBC 1010.1 in the same wall and within 10 feet of the revolving door.
Revolving doors cannot be part of a required accessible route.

Manual Revolving Doors
Max Door Speed

Door Diameter (Feet)	Max Speed (RPM)
6	12
7	11
8	10
9	9
10	8

Auto/Power Revolving Doors
Max Door Speed

Door Diameter (Feet)	Max Speed (RPM)
8	7.2
9	6.4
10	5.7
11	5.2
12	4.8
12.5	4.6
14	4.1
16	3.6
17	3.4
18	3.2
20	2.9
24	2.4

Revolving Doors in Egress Components must meet the following requirements:

Count towards no more than 50% or required egress width or capacity.
Each door counts towards a maximum of 50 occupants when performing egress calculations.
Maximum breakout force of 130 pounds.

Revolving doors that are not egress components must have a breakout force of 180 pounds or less. A breakout force of more than 180 pounds is permitted if the breakout force reduces to 130 pounds or less under one of the following conditions:

Door power failure
Sprinkler system activation
Smoke detector activation with 75 feet of the revolving doors
Activation of a manual control switch in a clearly identified location

Power-Operated Doors

Power operated doors are common in building entrances, as well as in occupancies where people may struggle to open a door by themselves, such as a Group I-2 nursing home.

Horizontal sliding doors, like you might see an an airport, are an example of power operated doors.

Any egress door that is operated or assisted by power must have the capability to be manually opened or closed. The forces required to open the doors must comply with IBC 1010.1.3 door opening force requirements, except the force to set the door in motion must not exceed 50 pounds. The door must have the capability to open from any position to the full width of the opening when a force is applied on the egress side.

Power-operated swinging doors, power-operated sliding doors and power-operated folding doors must comply with BHMA A156.10. Power-assisted swinging doors and low-energy power-operated swinging doors must comply with BHMA A156.19. (2018 and Beyond): Low-energy power-operated sliding doors and low-energy power-operated folding doors must comply with BHMA A156.38.

Exceptions to the above requirements:

Group I-2 occupancies
Special purpose horizontal sliding, accordion or folding doors (see related section in this article)
For a biparting door in the emergency breakout mode, a door leaf located within a multiple-leaf opening is exempt from the minimum 32-inch single-leaf requirement, provided that a minimum 32-inch clear opening is provided when the two biparting leaves meeting in the center are broken out.

Special Purpose Horizontal Sliding, Accordion or Folding Doors

Special purpose doors, such as horizontal sliding doors, are most commonly used in situations where a fire door is needed in an egress path but there is a desire to have the door normally open, or perhaps concealed. A sliding or folding fire shutter would fall into this category. These are the only type of doors in this article that specifically require an integrated standby power supply, typically provided as a battery pack above the door.

A horizontal sliding fire door with egress functionality (image courtesy of Won-Door).

Horizontal sliding, accordion or folding doors can be used in all occupancies except Group H when allowed by Exception 6 of IBC 1010.1.2. Use of these doors requires the following:

The doors are power operated and are capable of being operated manually in the event of power failure.
The doors are openable by a simple method from both sides without special knowledge or effort.
The force required to operate the door cannot exceed 30 pounds to set the door in motion and 15 pounds to close the door or open it to the minimum required width.
The door must be openable with a maximum force of 15 pounds when a force of 250 pounds is applied perpendicular to the door adjacent to the operating device.
The door assembly must comply with the applicable fire protection rating and, where rated, must be:
1. Self-closing or automatic closing by smoke detection in accordance with IBC 716.2.6.6.
2. Installed in accordance with NFPA 80.
3. Comply with IBC 716.
The door assembly must have an integrated standby power supply.
The door assembly power supply must be electrically supervised.
The door must open to the minimum required width within 10 seconds of the operating device.

Locking Arrangements in Educational Occupancies

Locking of egress doors in educational occupancies has been a hotly-debated topic in recent code cycles. Some argue that being able to lock a classroom door from the inside is necessary to protect occupants during certain emergency situations. Others argue that this actually poses a greater risk to occupants inside the classroom. The requirements for such locking arrangements are provided below.

In Group E occupancies, Group B educational occupancies and (2021 only) Group I-4 occupancies, egress doors from classrooms, offices and other occupied rooms with locking arrangements designed to keep intruders from entering the room are permitted with the following requirements:

The door is capable of being unlocked from outside the room with a key or other approved method. Remote door unlocking is permitted in addition to the key.
The door is openable from within the room per IBC 1010.2
Modification are not permitted to listed panic hardware, fire door hardware or closers.
(2021 only) Modifications to fire doors assemblies must be in accordance with NFPA 80.

Security Grilles

Secutiry grilles are an important part of building security systems, particularly in retail spaces such as a shopping mall. The IBC allows security grilles in Group M occupancies, as well as Groups B, F and S.

In Groups B, F, M and S, horizontal sliding or vertical security grilles are permitted at the main exit and must be openable from the inside without the use of a key, special knowledge or effort when the space is occupied. The grilles must remain secured in the full-open position anytime the space is occupied by the general public. Where two or more means of egress are required, no more than half of the exits or exit access doorways can be equipped with security grilles.

Group I-1 and I-2 Controlled Egress Doors

Group I-1 and I-2 occupancies include assisted living facilities, nursing homes, hospitals, psychiatric treatment centers, all facilities where people receiving care may require some level of containment. There are many situations where allowing a care recipient to freely exit may actually endanger that person or others. The IBC recognizes this risk and provides an avenue to provide locking control on egress doors in such occupancies.

Electric locking systems are permitted in Group I-1 and I-2 occupancies where the clinical needs of the care recipient require their containment. In order to use this code provision, the building must be either fully sprinkler-protected or equipped throughout with smoke detectors and meet all of the following requirements:

The door must unlock upon actuation of the sprinkler or smoke detection system.
The door must unlock upon power loss.
The door must have an unlocking switch, located at the fire command center, nursing station or other approved location, that directly breaks power to the lock.
No more than one controlled egress door before reaching an exit
Door unlocking procures must be included and approved in the required Fire Code emergency planning (see IFC Chapter 4).
All clinical staff must have a key or other means to operate the locked door
Emergency lighting is required at the door.
The door locking system must be UL 294 listed.

Exceptions: Items 1-4 above do not apply to the following situations:

Areas where persons require restraint or containment as part of the function of a psychiatric treatment area or (2021 only) cognitive treatment area.
Where a listed egress control system is used to reduce child abduction risk from nursery and obstetric area of a Group I-2 hospital.

Delayed Egress

Using a delayed egress system is one of the most common approaches to achieve some level of access control on an egress door. They provide a deterrent to occupants using the door unless there is a true need (e.g. a fire emergency), but still allow for full egress use after the delay period. A key limitation of delayed egress systems is they are limited by occupancy , for example, Group A spaces cannot use delayed egress systems, regardless of the occupant load.

Where permitted:

2015:
Delayed egress locking systems are permitted in any occupancy except Groups A, E or H when the building is fully sprinkler protected per NFPA 13 or provided with smoke/heat detection throughout.

2018 and Beyond:
Delayed egress locking systems are permitted in the following situations when the building is fully sprinkler protected per NFPA 13 or provided with smoke/heat detection throughout.

Group B, F, I, M, R, S and U
Group E classrooms with an occupant load less than 50
In courtrooms, on other than the main exit doors, when the building is fully sprinkler protected per NFPA 13.

The delayed egress locking system must meet all of the following requirements:

The delay electronics must allow immediate and free egress upon actuation of the sprinkler system or fire detection system.
The delay electronics must allow immediate and free egress upon power loss.
The delay electronics must have the capability to be deactivated from the fire command center or other approved location.
When an effort is applied to the egress door hardware for not more than 3 seconds, an irreversible process must star that allows for the egress door to open in 15 seconds or less. The irreversible process must activate an audible signal near the door. Once the delayed egress door has been deactivated, the door can only be rearmed by manual means.
1. Exception: Where approved by the AHJ, a delay of not more than 30 seconds is permitted.
The egress path cannot pass through more than one delayed egress locking system.
1. 2015 Exception: In Groups I-2 or I-3, the egress path can pass through up to two delayed egress locking systems if the combined delay is 30 seconds or less.
2. 2018 Exception: In Groups I-2 or I-3, the egress path can pass through up to two delayed egress locking systems if the combined delay is 30 seconds or less. In Groups I-1 or I-4, the egress path can pass through up to two delayed egress locking systems if the combined delay is 30 seconds or less and the building is fully sprinkler protected per NFPA 13.
3. 2021 Exception: In Groups I-1 Condition 2, I-2 or I-3, the egress path can pass through up to two delayed egress locking systems if the combined delay is 30 seconds or less. In Groups I-1 Condition 1 or I-4, the egress path can pass through up to two delayed egress locking systems if the combined delay is 30 seconds or less and the building is fully sprinkler protected per NFPA 13.
A sign must be provided on the door and located above and within 12 inches of the door exit hardware:
1. For doors swinging in direction of egress, the sign must read “PUSH UNTIL ALARM SOUNDS. DOOR CAN BE OPENED IN 15 [30] SECONDS.”
2. For doors swinging in against the direction of egress, the sign must read “PULL UNTIL ALARM SOUNDS. DOOR CAN BE OPENED IN 15 [30] SECONDS.”
3. The sign must comply with the visual character requirements in ICC A117.1.
4. Exception: Where approved in Group I occupancies, the sign is not required where care recipients have a clinical needs requiring restraint or containment as part of the function of the treatment area.
Emergency lighting must be provided on the egress side of the door.
The delayed egress systems must be UL 294 listed.

Sensor Release of Electrically Locked Doors

Electrically locked doors using a sensor release are frequently used in situations where it is helpful to have an egress door unlock prior to an occupant physically reaching the door. Note that this type of door release functionality can be used in conjunction with an electromagnetic locking mechanism (Mag Lock).

Sensors must be mounted such that the door unlocks as an occupant is approaching.

Where Permitted:

2015:
Sensor release locks are permitted on any egress door in Groups A, B, E, I-1, I-2, I-4, M, R-1 or R-2 occupancy.

2018 and Beyond:
Sensor release locks are permitted on any egress door except in Group H occupancies.

Sensor release locks must be installed and operated per the following requirements:

Sensor installed on egress side of door to detect an occupant approaching the door and cause the electric lock system to unlock.
Door unlocks upon loss of power or signal to the sensor.
Door unlocks upon loss of power to the lock or locking system.
Doors can be unlocked from a manual device located 40” to 48” above the floor and with 5 feet of the doors. The unlocking device must be readily accessible and be clearly identified with a “PUSH TO EXIT” sign. The unlocking device must directly interrupt power to the lock independent of other electronics and keep the door unlocked for at least 30 seconds.
Door unlocks upon activation of the building fire alarm system and remain unlocked until fire alarm system is reset.
Door unlocks upon activation of the sprinkler system or fire detection system and remain unlocked until the fire alarm is reset.
Door lock system must be UL 294 listed.
(2021 Only) Emergency lighting must be provided on the egress side of the door.

Electromagnetically Locked Doors

Electromagnetically locked egress doors, commonly referred to as “Mag Locks” are permitted in Group A, B, E, I-1, I-2, M, R-1 and R-2 occupancies. Use of such locks requires a built-in switch on the door and compliance with the following:

Hardware is affixed directly to the door leaf and has an obvious method of operation under all lighting conditions.
Hardware can be operated with one hand.
Operating the door hardware immediately interrupts power to the Mag Lock and unlocks the door immediately.
Door unlocks upon lows of power to the locking system.
Where panic or fire exit hardware is required, operation of that hardware also releases the Mag Lock.
Lock system must be UL 294 listed.

Door Hardware Release of Electrically Locked Doors

Starting in 2018, the Mag Lock section above was expanded to any electric locking system with a door hardware release. The requirements here are essentially the same as the Mag lock requirements from 2015.

Door hardware release of electric locking systems on egress doors is permitted in all occupancies except Group H and requires compliances with the following:

Hardware is affixed directly to the door leaf and has an obvious method of operation under all lighting conditions.
Hardware can be operated with one hand and meets IBC unlatching requirements.
Operating the door hardware immediately interrupts power to the lock and unlocks the door immediately.
Door unlocks upon lows of power to the locking system.
Where panic or fire exit hardware is required, operation of that hardware also releases the lock.
Lock system must be UL 294 listed.

Correctional Facilities

Correctional and detention facilities are permitted to have locked egress doors when occupants are required to have controlled movements for security purposes. Such doors must have an egress control devices that unlocks the door manually and by at least one of the following means:

Activation of the building sprinkler system
Actvaition of a manual fire alarm pull station
A signal from a constantly attended location.

In the 2015 IBC, use of this provision is limited to Groups A-2, A-3, A-4, B, E, F, I-2, I-3, M and S occupancies within correctional and detention facilities. In 2018 and beyond, use of this section is permitted in any building within a correctional and detention facility.

Stairway Doors

In some cases, stair doors can be locked from the inside, but never in the direction of egress.

Generally, interior stair doors must be openable from both sides without the use of a key or special knowledge, though the following exceptions allow you to lock the stair door:

Stair discharge doors can be locked from the outside (must be unlocked in direction leaving the stair).
Stair doors in high rise buildings complying with IBC 403.5.3 (see section below).
(2015 Only): In stairs serving 4 stories or fewer, stair doors can be locked from the inside provide they have the capability of being simultaneously unlocked (without unlatching) by a signal from the fire command center or location inside the main entrance of the building.
(2018 and Beyond): Stair doors can be locked from the inside provide they have the capability of being simultaneously unlocked (without unlatching) by a signal from the fire command center or location inside the main entrance of the building.
Stair doors in Group B, F, M and S occupancies where the only interior access to a tenant space is from the exit stair can be locked from the inside of the stair (must be unlocked in direction of egress).
Stair doors in Group R-2 dwelling units where the only interior access to the unit is from the exit stair can be locked from the inside of the stair (must be unlocked in direction of egress).

In high rise buildings, stairway doors can be unlocked from the stairway side provided they have the capability of being unlocked (without unlatching) by a signal from the fire command center. when this provision is used, a telephone or other two-way communication system connected to a constantly attended location is required on every fifth floor in every stairway with locked doors.

Panic and Fire Exit Hardware

Panice and fire exit hardware itself does not involve locking a door. Rather, panic or fire exit hardware can be used in conjunction with one of the locking arrangement described in this article.

New Calculator: Fire Resistance for Wood Walls

5/21/2021

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I recently helped an architect design a wood-framed wall assembly with different membrane arrangements on each side of the wall. We used the calculated fire resistance approach from IBC 722 to achieve a one-hour rating for the wall. This project led me to create a new tool that calculates the fire resistance of the wall assembly based on the materials that you choose for each side. Check it out at the link below!

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Explaining Fire Resistance vs. Fire Protection Ratings for Opening Protectives

5/14/2021

In the A/E world, there is much confusion regarding the definition of fire protection rating and fire resistance rating when designing doors, windows, transoms, sidelights and other openings in rated construction. These terms are often used interchangeably by mistake, but they represent two very different types of assemblies. A third term, "fire rating", is often used as well, making the distinction even more confusing. In this article, we'll review the differences between fire resistance ratings and fire protection ratings and show you how to determine the requirements for your specific situation. All code references are to the 2018 IBC.

Before distinguishing between fire-resistance-rated assemblies and fire-protection-rated assemblies, it's important to note that both of these are types of fire-rated assemblies. So if someone refers to a fire-rated glazing assembly, they could be potentially referring to either a fire-resistance-rated assembly or a fire-protection-rated assembly. The majority of the requirements for either type of assembly come from IBC Table 716.1(2).

Fire Resistance Rating

Fire-resistance-rated assemblies are those that have been tested to ASTM E119 or UL 263. This is the same test that is used for rated wall, floor and ceiling assemblies. Therefore, if you have a door, window, shutter or any other type of openings protective that is tested to ASTM E119 or UL 263, it is treated no differently than a rated wall or floor. There are no limitations to the area or location where you can provide such opening protectives.

Functionally, these tests measure an opening protective's ability to stop the transmission of smoke/flames AND to limit the transmission of radiant heat. In order to pass ASTM E119 or UL 263, assemblies must limit the temperature rise on the non-fire side of wall/floor to 250 degrees or less.

Any fire-rated glazing assembly, whether a fire-resistance-rated assembly or fire-protection-rated assembly, is required to be labelled per IBC 716.1.2.2. The markings for these assemblies are shown in IBC Table 716.1(1) and replicated in the table provided below. For fire-resistance-rated glazing, you are looking for markings containing either a "W" or "F". If the marking does not contain either of these letters, the assembly is not fire-resistance-rated. Fire doors are required to be labelled per the requirements of NFPA 80.

Test	Marking	Definition
ASTM E119 or UL 263	W	Meets wall assembly criteria
ASTM E119 or UL 263	F	Meets floor/ceiling assembly criteria.
NFPA 257 or UL 9	OH	Meets fire window assembly critiera including host stream
NFPA 252 or UL 10B or UL 10C	D	Meets fire door assembly criteria.
NFPA 252 or UL 10B or UL 10C	H	Meets fire door assembly hose stream test.
NFPA 252 or UL 10B or UL 10C	T	Meets 450 degree temperature rise criteria for 30 minutes.
-	XXX	The time in minutes of the rating of the glazing assembly.

Fire Protection Rating

Fire-protection-rated assemblies are those that have been tested to one of the following:

NFPA 252, Standard Methods of Fire Tests of Door Assemblies
NFPA 257, Standard on Fire Tests for Window and Glass Block Assemblies
UL 9, Standard for Safety Fire Tests of Window Assemblies
UL 10B, Standard for Fire Tests of Door Assemblies
UL 10C, Standard for Positive Pressure Fire Tests of Door Assemblies

Functionally, these tests measure an opening protective's ability to stop the transmission of smoke/flames but do not test for the transmission of radiant heat. There are a number of limitations on the size and use of fire-protection-rated assemblies.

Area Limitations
Fire-protection-rated openings have area limitations as indicated in the table below. Remember that these apply only to fire-protection-rated assemblies. Fire-resistance-rated opening protectives are treated no differently from the wall itself and are not limited in area.

Type of Opening Protective	Type of Wall	Area Limitation	Exceptions	IBC Reference
Fire Door	Fire Wall	156 SF per opening 25% of the length of the wall	Not limited to 156 SF when both buildings are fully-sprinklered per NFPA 13	706.8
Fire Door	Fire Barrier	156 SF per opening 25% of the length of the wall	Not limited to 156 SF when both buildings are fully-sprinklered per NFPA 13; No area limitations for fire doors serving rated stairs/ramps	707.6
Fire Window	Fire Barrier	156 SF per opening 25% of the length of the wall	Not limited to 25% of the wall when used in atrium separation walls	707.6
Fire Window	All	25% of the wall area	-	716.3.2.1.2

Fire Doors
In interior fire doors that require a 1-hour rating or greater, fire-protection-rated glazing is permitted in the door vision panel up to 100 square inches. The glazing in the door vision panel is required to pass the hose stream test and bear the "D" and "H" markings. The duration (in hours) of the required rating depends on the type and rating of the wall itself - specific requirements are provided in IBC Table 716.1(2). If a vision panel greater than 100 square inches in area is desired, the vision panel must be fire-resistance-rated glazing and bear the "W" marking. Additionally, vision panels exceeding this area in exit stairways, ramps and passageways must meet the maximum temperature rise criteria of 450 degrees after 30 minutes and bear the "T" marking. There is an exception for this temperature rise criteria if the building is fully-sprinkler protected in accordance with NFPA 13 or 13R. Finally, sidelights and transoms adjacent to fire doors that require a 1 hour rating or greater are required to have a fire-resistance-rating equal to that of the wall itself; fire-protection-rated glazing is not permitted in these.

If the fire door requires a 45 minute rating or less, fire-protection-rated glazing is permitted in the door vision panel up to the maximum size tested. There is no requirement for fire-resistance-rated glazing in such doors. Sidelights and transoms adjacent to these doors are required to have a fire protection rating of either 20 or 45 minutes depending on the location. Refer to IBC Table 716.1(2) for the specific requirements.

Fire doors in rated exterior walls have slightly different requirements. If the exterior wall has a rating greater than 2 hours, the fire door is required to have at least a 90-minute rating and a fire-protection-rated vision panel is permitted up to 100 square inches in area. Any sidelights and transoms are required to have a fire-resistance-rating the same as the wall itself.

Exterior walls rated 2 hours or less are permitted to have fire-protection-rated glazing in the door vision panel, sidelight and transom. The rating requirement for these elements is the same as the door itself.

Fire Windows
Fire-protection-rated glazing is permitted in certain fire windows in interior wall assemblies, up to a maximum rating of 45 minutes. Fire windows in fire walls and fire barriers (excluding atrium separation, incidental use separations and occupancy separations) are required to have fire-resistance rated glazing. Refer to the table below, based on requirements form IBC Table 716.1(3). Note that walls allowing fire-protection-rated glazing can be provided with fire-resistance-rated glazing as indicated, but this is not required.

Type of Wall Assembly	Required Wall Rating	Minimum Fire-Protection-Rating Glazing	Minimum Fire-Resistance-Rated Glazing
Fire Wall	All	Not Permitted	Same as wall rating
Fire Barriers*	All*	Not Permitted	Same as wall rating
Atrium Separations, Incidental Use Separations, Mixed Occupancy Separations	1	45 minutes	1 hour
Fire Partitions	1	45 minutes	1 hour
Fire Partitions	30 minutes	20 minutes	30 minutes
Smoke Barriers	1	45 minutes	1 hour

*except those noted in the next row

Fire-protection-rated glazing is permitted in all fire windows in exterior walls, as described in the table below. IBC Table 705.8 provides requirements for opening protectives in exterior walls, so be sure to refer there as well. Depending on the fire separation distance, you may be permitted to have unprotected openings in a rated exterior walls. Conversely, if the fire separation distance is less than 3 feet, you are not permitted to have any openings in the exterior wall, even if they have a fire protection rating. Fire-resistance-rated glazing is always permitted since it must meet the same test criteria as the wall itself.

Type of Wall Assembly	Required Wall Rating	Minimum Fire-Protection-Rated Glazing	Minimum Fire-Resistance-Rated Glazing
Exterior Walls	Greater than 1	1.5 hours	Same as wall rating
Exterior Walls	1 hour	45 minutes	1 hour
Exterior Walls	30 minutes	20 minutes	30 minutes

Summary

There are two types of fire-rated openings protectives: fire-resistance-rated and fire-protection-rated assemblies. Fire-resistance-rated assemblies have to meet the same test criteria, ASTM E119 or UL 263, as a rated wall or floor assembly. Since the test is the same, there are no size or location limits for where you can provide fire-resistance-rated protectives. Fire-protection-rated assemblies are tested to lesser criteria and are limited in size and location. Full requirements for both types of assemblies are found in IBC Table 716.1(2).