13R - Non-residential Sprinklers in Suites

[Haldorson]

Hello,

I have a 3-storey wood framed residential building with no common areas. Each unit has direct access to grade. The building will be sprinklered to NFPA 13R.

The issue is the upper level of the suites has a ceiling slope of 12:12 and therefore residential sprinklers are not permitted and standard sprinklers must be installed.

Is the hydraulic calculation still the most demanding 4 sprinklers in a compartment with LH density because of the standard sprinklers, or does it become a area/density calculation up to 1500 square feet?

 

[TravisMack]

You need to be careful. I believe that 13R limits the amount of non-residential sprinklers in a dwelling unit to no more than 4. If you are going to exceed 4 non-residential sprinklers, then it is my understanding that you have to go to NFPA 13 for the building design.

6.2 Use of Sprinklers.
6.2.1 Inside Dwelling Units.
6.2.1.1 Listed residential sprinklers shall be used unless another type is permitted by 6.2.1.3 or 6.2.1.4.
6.2.1.2 Residential sprinklers shall not be used on systems other than wet pipe systems unless specifically listed for use on that particular type of system.
6.2.1.3 Listed quick-response sprinklers shall be permitted to be installed in dwelling units meeting the definition of a compartment, as defined in Section 3.3, where no more than four sprinklers are located in the dwelling unit.
6.2.1.3.1 Where quick-response sprinklers, including extended coverage quick-response sprinklers, are used, the density/area requirement shall be a minimum of 0.1 gpm/ft2 (4.1 mm/min) over the entire dwelling unit.
6.2.1.3.2 Where extended coverage quick-response sprinklers are used, the flow shall be sufficient to meet the listing of the sprinklers at the spacing for which they are being used.
6.2.1.4 Quick-response sprinklers discharging a minimum of 0.1 gpm/ft2 (4.1 mm/min) shall be permitted to be used in mechanical closets.



Travis Mack
MFP Design, LLC

http://www.mfpdesign.com