Engineering Judgment (EJ) and Firestop Custom Detail (FCD) Request Guidance (Canada)

Fire compartmentation, a passive form of fire protection, is achieved using fire-resistant rated assemblies such as walls, partitions, or floors to separate building spaces. These barriers are designed to minimize the spread of smoke and fire from the area of origin to adjacent compartments. The effectiveness of a fire-resistant rated assembly is dependent on the inherent fire-resistance rating of the assemblies, construction methods, and other aspects such as openings that occur due to joints or penetrations.
Penetrations and joints in fire-resistance rated assemblies (gypsum walls, concrete floors, etc.) can be treated using tested firestop systems. These tested systems are documented and expressed in the form of listed or certified systems by nationally recognized independent testing laboratories, such as Underwriters Laboratories (UL), FM Global, and Intertek. As an example, a Hilti UL listing (W-L-1054) is shown in Figure 1. Listed/certified firestop systems should always be used instead of an engineering judgment when possible. A catalog of Hilti’s listed firestop systems can be found at Fire compartmentation, a passive form of fire protection, is achieved using fire-resistant rated assemblies such as walls, partitions, or floors to separate building spaces. These barriers are designed to minimize the spread of smoke and fire from the area of origin to adjacent compartments. The effectiveness of a fire-resistant rated assembly is dependent on the inherent fire-resistance rating of the assemblies, construction methods, and other aspects such as openings that occur due to joints or penetrations.
Penetrations and joints in fire-resistance rated assemblies (gypsum walls, concrete floors, etc.) can be treated using tested firestop systems. These tested systems are documented and expressed in the form of listed or certified systems by nationally recognized independent testing laboratories, such as Underwriters Laboratories (UL), FM Global, and Intertek. As an example, a Hilti UL listing (W-L-1054) is shown in Figure 1. Listed/certified firestop systems should always be used instead of an engineering judgment when possible. A catalog of Hilti’s listed firestop systems can be found at Hilti.ca/firestops. 

Figure 1: W-L-1054

When is an Engineering Judgment (EJ), or Firestop Custom Detail (FCD) Needed?

           “Firestop custom detail” is another term used for an engineering judgment in some provinces, such as British Columbia, Canada. When a listed firestop system is not available for the given field application, an EJ/FCD provides an alternative firestop solution to specifically address openings or voids within, or between, fire-resistance rated assemblies to meet code requirements. To help ensure accuracy and appropriateness of an EJ/FCD, the International Firestop Council (IFC) provides a list of guidelines regarding how to evaluate EJs/FCDs. Visit https://www.firestop.org/ to find the specific criteria. The Hilti Fire Protection Design Team uses data from tested and listed systems, as well as data from standardized fire test results that might not have a corresponding listing and applies them to the specific conditions using engineering principles. If there are any specific local code requirements that must be complied with that are different from the requirements of the National Building Code of Canada, communicate this requirement to the Hilti Fire Protection Design Team when requesting an FCD or EJ. 

Components of an Engineering Judgment:

           EJs/FCDs can be as simple as a wall with a penetration and sealant around the pipe, but they can also be complex and require multiple different views and firestopping materials. It is important to understand the major components of an EJ/FCD so the necessary information can be accurately and completely communicated to the Hilti Fire Protection Design Team, to better ensure the application and solution developed align.
 
For EJs/FCDs there are 6 major components that must be included when requesting an EJ/FCD. Engineering Judgments and Firestop Custom Details are contractor, project, and application specific:
1.    Job information (project name and contractor/designer);
2.    The F-rating (and FT-rating, if applicable) required;
3.    Details of the substrate(s) (e.g. wall, floor, floor-ceiling, or roof/ceiling assembly), including the assembly listing number if available;
4.    If applicable the penetrating item(s) (e.g., material, size, etc.);
5.    The dimensions of any spacings, gaps, material thickness, etc. (e.g. annular space around the penetrating item, joint width between two assemblies, etc.); and
6.    The firestop material you would prefer.
 

Substrates/Fire-Resistance Rated Joint Assemblies:

As mentioned above in item 3, important details to provide for the fire-resistant rated assemblies, or substrates, are as follows:

• The type of construction for each assembly, (e.g. gypsum wall, gypsum shaft wall, concrete floor, concrete floor over metal deck, etc.),
• The thickness of concrete, plaster, CLT, and heavy timber assemblies, (for concrete-metal-deck applications, concrete thickness is measured from the top of the flutes of the decking), and
• The width of studs being used in gypsum assemblies.

If applicable, please provide the fire-resistance rated design reference, manufacturer provided CAN/ULC-S101 reports, or other standard specific performance report for the assemblies in which the fire-resistant rated joint solution will be installed. These documents provide valuable information to the Hilti Fire Protection Design Team which will assist them in understanding the scope of the requested condition and requested fire resistance features.

Due to the unique design of most curtain walls, for perimeter joint (edge-of-slab) applications, the architectural details of the perimeter joint and the facade must also be provided. Be sure to note the slab edge thickness, the joint width and any unique, known conditions of the façade which may not be noted/visible within the photos or details.

To better facilitate the installation of the EJ/FCD solution, the details and limitations on accessibility should be provided. While most listed systems require sealant on both sides of a wall assembly or the top side of floor assemblies, single side and underside installation methods may be achievable in many cases.

Membrane or Through-Penetrations:

For through-penetrations per item 4 above, the following information is required:

• The material of the penetrating item(s) (e.g. steel, cast iron, copper, PVC, PEX, etc.);
• The maximum size of the penetrating item(s) (nominal pipe diameter or penetrant dimensions);
• The wall thickness of the penetrating item(s) (pipe schedule [sch] or the standard dimension ratio [SDR]) if applicable;
• The gauge of steel (for metallic items other than pipes);
• The types of cables, size of the cable bundles and the percentage of the cross-sectional opening or cable tray that they occupy;
• Any sleeve that may be installed (sheet metal sleeve, steel pipe sleeve, etc.), the extension of the sleeve, and the wall thickness of the sleeve (in gauge or sch);
• The insulation type (e.g. glass fiber, AB/PVC, cellular foam, etc.) and insulation thickness if applicable.
• Whether the piping system is an “open” (unpressurized) or “closed” (pressurized) system.

The information provided above will play a direct role in the solution the Hilti Fire Protection Design Team can offer. Within the construction industry, there are multiple types and varieties of piping. For combustible piping, small changes in the chemical make-up can drastically change the way pipes burn and degrade in fire testing. Therefore, it is critical to identify the specific piping material and/or insulating material (type, overall size and wall thickness) to help ensure the firestop solution provided is adequate and performs as expected. The National Building Code of Canada requires combustible pipe firestop systems to be tested at a 50-pascal pressure differential for combustible drain/waste/ventilation, water distribution, central vacuum, and polypropylene pipes. In some jurisdictions, there is an exception in the building code that allows for a 2.5-pascal pressure difference (U.S. standard) to be acceptable. Please consult the local building code for requirements regarding combustible pipe penetration firestop systems. For example, in Ontario only, confirm whether the provincial code exception waiving the 50Pa test pressure for penetration firestop testing for sprinklered areas is being used (and therefore 2.5Pa tests are appropriate for reference). The Authority Having Jurisdiction (AHJ) will have final determination of acceptance. 

Figure 2

Penetrant Spacing:

The opening size and annular space directly affect the type of firestop material for a given condition. Annular space is the distance from the penetrating item(s) to the edge of the opening in the fire resistance rated substrate/assembly. For multi-penetrant installations, annular space also applies to the spacing between individual penetrants within the same opening/installation. The UL Guide Info - Through Penetration Firestop Systems Certified for Canada clarifies when a penetrant is installed in a rectangular opening, annular space is to be measured from the nearest edge of the penetration to the side of the opening perpendicular to that edge, as shown in Figure 2. Annular space is not to be measured diagonally unless measuring the distance between two penetrants in the same opening. Both the minimum and maximum annular space must be established to determine if a given firestop solution would be expected to provide the needed fire-resistance rating. When the annular space or joint width becomes too large, additional firestopping measures need to be taken to protect the annular space around the penetration.

When a penetration is in contact with the opening (min. 0” annular space), a bead of firestop sealant is typically required to be applied at the interface of the pipe and the opening. It is important to note the point of contact to the periphery of an opening at a single point is not the same as continuous point of contact between a penetrant and the entirety of the opening (i.e. nominal 0” annular space). Continuous point of contact is only allowed by a few systems (ex. W-L-1054 or W-J-1067) which include a specific note stating, “pipe may be installed with continuous point of contact.” 

For systems involving multiple penetrations, there are requirements for the annular space between penetrants, and the annular space between penetrants and the opening. The Hilti Fire Protection Design Team needs this information to understand the needed fill material, or to account for any additional attachments required for penetrations (e.g. steel angles on a duct, a collar on a plastic pipe, etc.) to provide more relevant options for a given condition. 

Construction Joint Width:

The joint width is the measured space between two fire resistance rated assemblies, or in some cases a fire-resistance rated wall or barrier extending out to a non-fire resistance rated roof or wall assembly. In the case of gypsum wall assemblies (as shown in figure 3), the joint width is the measured dimension from the edge of the gypsum boards to the adjacent assembly.

For conditions with concrete over metal deck floor assemblies, it is important to note that the joint width is defined as the distance from the lowest point of the flutes, known as the valley of the flutes, to the top of the wall assembly underneath (as shown in figure 4). Providing the correct joint width is necessary because as the joint width becomes larger, additional protection measures may be required. For example, in a head-of-wall condition with a small joint width (typically 1” or less), this may be detailed to show a sealant only solution. Once the condition has exceeded the joint width capabilities of the sealant, the Fire Protection Design Team may need to add mineral wool and in extreme cases, steel cover plates.

The joint width is also a major variable when considering the movement of a joint system. The smaller the joint width, the smaller the available deflection. When the joint width is larger than the referenced system, the given linear deflection increases and the percentage of compression and extension decreases. 

Requested Firestop Material:

It is common for customers to request a specific type of firestop for a given condition based on the product they might have on-hand or may have preferred methods of installation. Our Fire Protection Design Team will try to meet them However, it is important to note that there are conditions where it is not possible to achieve a fire-resistance rating with a requested product due to a lack of testing, compatibility issues, or feasibility of installation. When one of these issues arise, an engineer on the Hilti Fire Protection Design Team will reach out to the customer to discuss any alternative solutions.

ADDITIONAL RATINGS BEYOND FIRE-RESISTANCE:

Through-penetration and joint firestop EJs/FCDs typically only address the fire-resistance rating, or F-rating, of an assembly. The CAN/ULC-S115 test standard allows for additional ratings when specifically tested. One additional rating which may be tested and recorded under CAN/ULC-S115 is an air leakage rating (L-rating). An L-rating is never required by code in Canada.

The temperature rating (FT-rating) is required to be tested and reported according to CAN/ULC-S115 but might not always be required for every application. Check your local building code for requirements and exceptions. The AHJ will have final determination of acceptance.

Where additional ratings are requested to be noted/specified on an EJ/FCD, the Hilti Fire Protection Design Team will evaluate the presented conditions and provide notes or ratings where possible. For EJs/FCDs where through-penetration firestop systems are required to have a stated FT-rating, the project location for the EJ/FCD (city and province) must be provided along with any accessibility issues surrounding the penetration. L-ratings are only listed on through-penetration and fire-resistance rated joint EJs/FCDs upon request. When required for a condition, please make this clear in your request to the Hilti Fire Protection Design Team. If the L-rating needs to be a specific value, please specify this in your request as well.

 The W-rating is a 24-hour water-leakage resistance rating that is detailed in US test method UL 1479. CAN/ULC-S115 does not include testing for W-ratings. This may cause some confusion because there are Hilti firestop listings that indicate they are tested to CAN/ULC-S115 and include a W-rating. The W-rating is included on these systems because the system was tested to the U.S. test standard, which does include testing for W-ratings. The W-rating is only applicable for the UL 1479 testing certification.

REQUESTING AN ENGINEERING JUDGMENT OR FIRESTOP CUSTOM DETAIL:

This article has identified the essential information that needs to be included in an EJ/FCD request to the Hilti Fire Protection Design Team. Providing the necessary information in a request to the Hilti Fire Protection Design Team allows the engineer working on the EJ/FCD to provide a more efficient and more accurate solutions.

To request an EJ or FCD please visit: Hilti.ca/ej