In NFPA 101, section 18.104.22.168 there is an allowance to install up to 6 sprinkler heads for the protection of a hazardous area without requiring a licensed sprinkler contractor and design. For many years we've provided this as an option when furnaces and boilers needed separation, but installing sheetrock on the ceiling is next to impossible. We'd provided all the criteria and required the installer to meet said criteria. What we found was that in most cases the math didn't work out for the required flow yet, plumbers would state they had met the criteria.
Wondering how many places see this option being used and how it is handled? For our municipal water system most residential building wouldn't be able to supply more than two heads using 22.214.171.124, thus requiring a smoke proof "enclosure" to reduce teh covered area. This also results in a major problem as the fuel burning appliance won't run cleanly or efficiently without adequate make-up air, resulting in doors being propped open.
Wondering what others have seen, done or required?