Determining Combined Supply Pipe Size
Determining Combined Supply Pipe Size
(OP)
Hello,
I have a project - 6,000 square foot industrial building - where I have been asked to confirm the required incoming combined supply pipe size. I have completed the sprinkler design and calculations and I can make it work adequately with a 4" incoming.
The domestic system requires a 3" pipe size.
Am I okay specifying a 4" incoming or should it be 6"?
Is there a rule-of-thumb that would be useful for me?





RE: Determining Combined Supply Pipe Size
is this in the US??????
RE: Determining Combined Supply Pipe Size
The incoming is combined domestic and fire.
This project is in Canada.
RE: Determining Combined Supply Pipe Size
RE: Determining Combined Supply Pipe Size
What are your flow requirements? Sprinkler = _?___ GPM. Domestic = __?__ GPM? If you're combining Spkr & Domestic in the same lateral (check with your AHJ), then:
Total Flow = Spkr + Domestic. Select a lateral pipe size that gives a reasonable velocity at your peak flow. Then, see if you can live with the resulting pressure drop in the lateral. Repeat the process until you achieve an optimum. It's called: Hydraulic Calculations.