Does the gable edge of an eave require fire rating?

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This video describes the application of Volume Two Part 3.7.2.4 to the gable edge of an eave.

Transcript

Does the gable edge of an eave require a fire rating?

What we're talking about is this bit shown in red, and when we're talking about the gable we're often thinking of a gable roof and gable end, but the question really is, is this part in red a wall, because the FRL of course is applied to a wall?

Well it is a wall, because it's an extension of that which commences at the ground level, and as the NCC definition of external wall says, it's the outer wall of a building, which isn't a separating wall. You can consider this to be a somewhat narrow definition, and it's relevant, we can satisfy ourselves further by looking at other sources of information. I like to keep a copy of a particular handbook with a titled glossary of building terms on my desk, and describes external walls as something enclosing the sides of a building, and that is exactly what those parts in red are doing.

They're enclosing the side of the building, in addition, they're in the same plane as the rest of the wall, it's therefore appropriate to consider these as part of the wall. So, the rest of the question about FRLs becomes the next thing to consider. 3.7.2.2 says that an external wall, which we've already established applies to these parts in red, must comply with 3.7.2.4, and 3.7.2.4 requires external walls to, among other things, have an FRL of 60/60/60 in certain circumstances. And note, in 3.7.2.4(a), it includes gables, and by extension the areas in red in our example.

Therefore, the areas formed by the eaves of the roof, and the gable end, are all part of the wall, and within 900 millimetres from the boundary, or 1800 millimetres from another building, on the same allotment, they of course require an FRL.

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