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Spatial Separation

Plumb-bob

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Joined
Aug 31, 2022
Messages
298
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BC
I have a duplex with a limiting distance that is requiring the exposing building face to have a 45 min FRR.

The proponent is proposing to use fire rated windows that conform to the CAN4-S106M standard in the affected wall. Would these windows be acceptable? I have seen fire shutters used in the past but not windows.

Does anybody have experience with these type of rated windows? I believe the frames will not have any insulation, will this cause condensation concerns?
 
Yes, they work from a fire perspective, but getting compliance with energy code could be more challenging.

Fire shutters might be easier (but ugly). Another option would be for an alternative solution for sprinkler protection of the opening. This is a relatively common solution that a fire protection engineer could provide and depending on the size and number of the windows, the heads could probably be served off the domestic line instead of a fully sperate sprinkler system.
 
The CAN4-S106M standard is NOT referenced in any part of NBC 2015, or NBC 2020, and therefore, you can't rely on it prescriptively.

Take note that 9.10.14 allows wired glass or glass block, OR a fire-rated closure to eliminate unprotected openings but this would would only apply if you have an "over-under" duplex; a side-by-side would fall into 9.10.15.

9.10.15 does not allow wired glass or glass block OR rated closures; the only way to get there is to invoke Part 3 [via 9.10.3.1(1)(a)], which allows safety glass/glass block [but be mindful of 3.2.3.5(2)] or rated closures [3.2.3.1(10)] - otherwise the only avenue is a wall assembly that meets CAN/ULC-S134 by testing (referenced in Part 9)

So as I see it: unless there's something in a CMHC equivalence document for your specific product allowing it to be treated as a rated closure under Part 3 with Code-referenced tests/standards [perhaps one of the referenced standards like Can/ULC S101 allows glazing to be rated by reference to CAN4-S106M?? Of this I am uncertain, and it would be the designer's job to show this], you're in Alternative Solutions proposal terrain, and in any event, the glazing must meet 9.36 prescriptively or the designer must show the end result of a prescriptive trade-off that meets 9.36.
 
The CAN4-S106M standard is NOT referenced in any part of NBC 2015, or NBC 2020, and therefore, you can't rely on it prescriptively.

Take note that 9.10.14 allows wired glass or glass block, OR a fire-rated closure to eliminate unprotected openings but this would would only apply if you have an "over-under" duplex; a side-by-side would fall into 9.10.15.

9.10.15 does not allow wired glass or glass block OR rated closures; the only way to get there is to invoke Part 3 [via 9.10.3.1(1)(a)], which allows safety glass/glass block [but be mindful of 3.2.3.5(2)] or rated closures [3.2.3.1(10)] - otherwise the only avenue is a wall assembly that meets CAN/ULC-S134 by testing (referenced in Part 9)

So as I see it: unless there's something in a CMHC equivalence document for your specific product allowing it to be treated as a rated closure under Part 3 with Code-referenced tests/standards [perhaps one of the referenced standards like Can/ULC S101 allows glazing to be rated by reference to CAN4-S106M?? Of this I am uncertain, and it would be the designer's job to show this], you're in Alternative Solutions proposal terrain, and in any event, the glazing must meet 9.36 prescriptively or the designer must show the end result of a prescriptive trade-off that meets 9.36.
CAN4-S106M is just the old name for CAN/ULC-S106. It is only referenced by Part 3 though.

In an objective based code, I think you would have a hard time not accepting the argument that a properly rated window does not contribute towards the aggregate area of glazed openings.

Remember, settled law in Canada is that code enforcement must include discretion. If you fail to utilize discretion in enforcement, you are infringing on an individual's Charter rights.
 
I have a duplex with a limiting distance that is requiring the exposing building face to have a 45 min FRR.

The proponent is proposing to use fire rated windows that conform to the CAN4-S106M standard in the affected wall. Would these windows be acceptable? I have seen fire shutters used in the past but not windows.

Does anybody have experience with these type of rated windows? I believe the frames will not have any insulation, will this cause condensation concerns?
If this is a duplex under 9.10.15, the windows are considered as glazed openings, not unprotected openings.
 
If this is a duplex under 9.10.15, the windows are considered as glazed openings, not unprotected openings. Windows with fire resistance rating are still glazed openings.
 
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