Sprinkler requirements for attic

[eatapeach]

NFPA states sprinklers are not required in concealed spaces filled with noncombustible insulation. I have an 18" attic/concealed space above the top floor (flat roof), so can I say this is a concealed space? or is it the attic, which I may not be exempt?

 

[cdafd]

Nfpa 13?

Nfpa 13R?

Were you going to fill it with non com insulation?

 

[eatapeach]

The design professional used 13, and yes, the contractor wanted to fill it with non-com insulation. It's an R-2 4 stories he could have designed it to 13R but I am not sure why he used 13 other than he just wanted to use the more stringent. Fir blocking every 1000 sq. ft has been installed on all floors with the exception of the attic is 3000 sq. ft., but the question came up does the top 18" (area between top ceiling and roof) have to be sprinkled since technically it's the attic, or could it be considered a concealed space and be filled with non-com insulation.

 

[cdafd]

I go with fill

Make sure it is non com

And the entire space must be filled!!!

Yes there is a two inch allowance

Most of the time I see blown in. We use to check to assure it was filled. Not easy and some of the installers do not understand the requirement.

Check back for what others think.

 

[TravisMack]

An attic is a concealed combustible space generally. There is not a distinction. If you have a shallow attic like you say, it is not uncommon to fill the space with noncombustible insulation so that you can avoid sprinklers.

There are many reasons why an R-2 occupancy 4 stories or less would require an NFPA 13 system. A few of them are the architect needed the area increase to get the building size he wanted, or maybe the municipality doesn't give a credit for fire flow if the building is protected by a 13R system vs 13.

This is something I have seen many contractors over the years have an issue with. Building and Fire code first. Sure, NFPA 13R says for residential buildings 4 stories or less, but that doesn't mean any residential building 4 stories or less. 13R is a lesser system than 13 and has good application. But, the building / fire code must be consulted first.

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