Exterior Projections less than 4'

[Glorified Plumber 84]

Possibly dumb question, but when NFPA 13 references exterior projections requiring fire sprinklers greater than 4' in width, are they referring to literal width or depth? I've always thought this as the distance the overhang projects away from the building, but maybe this is a massive oversight on my end?

 

[skdesigner]

The width is always the lesser of the two horizontal dimensions. The longer dimension is the length.

You could have a combustible projection extending 100' out from the building, but if the other dimension is 4' or less, no sprinklers required.

Similarly, you could have a combustible projection that runs 100' along the building, but if it only projects 4' or less out from the building, no sprinklers required.

 

[Glorified Plumber 84]

Haha yea I feel dumb, but thank you, that answers the question.

 

[skdesigner]

Lol no worries. This forum is a ghost town compared to what it used to be, so it's nice to be able to take a stab at questions every now and again.

 

[TravisMack]

Yeah. There is not as much activity as we used to have. NFPA 13 in I believe the 2022 edition actually defined width just as noted above. It is the lesser of the 2 dimensions. Length is the greater.

Travis Mack, SET, RME-G,
MEPCad, Inc
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