Do control joints in tilt-up concrete external walls require fire protection?

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This video describes how C3.1 Application of Part provides concession in Part C3 of the NCC.

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Do control joints in tilt-up concrete external walls require fire protection?

Of course we're talking about walls which need an FRL, like those on or close to a boundary which is a fire-source feature. Yes or no? Here's C3.1 Application of Part. And you can see there in (a)(i), that control joints between pre-cast concrete panel walls don't need to comply with Part C3, so long as they are not larger than necessary for the purpose. But then we turn to C3.16 Construction Joints. And C3.16 says if you have a construction joint like say a control joint, in a wall which needs an FRL for integrity and insulation, so that's the second and third numbers in the FRL rating of course.

Then you need to protect the construction joint, unless it's a joint in a fire-protected timber system which has cavity barriers. It might seem that the BCA has told me I don't have to do something, but then straight away tells me that I have to do it.

So which is it? Well, this is one of those times when it helps to remember that often a BCA clause is written to cover more than the situation that you are thinking of. Let me show you, here's what C3.16 is about. These are the sort of things that need to be protected. Control joints and things like that mentioned in the top box, which are in walls, beams, floors and so on, mentioned in the bottom box. It has to be in both things in order to be applied to C3.1.

Now, what C3.1(a) gives a concession for are: These things that are in green in both the top and bottom lists. And these things are a sub-set of what's listed in C3.16. If you have a control joint in a steel framed, clad external wall for instance, it needs to be protected. If you have a control joint in an internal concrete panel lift shaft wall, yes that needs to be protected as well.

But if it's anything that's green in both the top and bottom lists, like a control joint in an external, pre-cast wall, then under C3.1(a) you have a concession and you don't need to provide protection. So the answer's no, your external pre-cast concrete wall, or your external masonry wall for that matter, that wall needs to have an FRL, it doesn't need protection for the control joints, so long as they are not larger than necessary for the purpose.

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