Determining of Design Area in Hotel Building

Discussion created by alisaif2012 on Dec 4, 2016
Latest reply on Sep 2, 2020 by lswanson


      i need expert opinion on subject mentioned, I m working in MEP contracting company as a mechanical engineer, I need to perform fire sprinkler hydraulic calculation for one of our project "Hotel Building". i am facing issue to determining the design area in Hotel floor, as Sprinklers are distributed Room by Room. which make uneven distribution pattern of sprinklers.

Each Hotel Room is consist of following sprinklers:


Side wall sprinkler - Quick Response Extended Coverage Side Wall for Living and bedroom spaces

Pendent Sprinkler-  Standard response standard spray in Room entering lobby and corridors outside the room.

See attachment for better clarification.


According to NFPA -13

"For extended coverage sprinklers, the minimum design area shall be that corresponding to the hazard in Figure or the area protected by five sprinklers, whichever
is greater".


I need clarification on following in using Density/Area method.


Should i consider only 5 nos of Extended coverage quick response sprinklers irrespective of the rooms bounding. in this case flow and pressure requirement can easily find from selected data sheet.


Should i consider all type of sprinklers in room and adjacent corridor part. in this case then what will be the procedure to calculate flow and pressure requirement.