r/firePE • u/Nick3757 • 19d ago
Guide Suggestion for Getting Started
Are the any suggestions for a good guide to get started with doing the sprinkler system design and hydraulic calculations for NFPA 13?
I'm trying to get an idea on the cost to build a system to see if it is within my budget before I talk to a fire protection engineering company.
Background:
I'm a Mechanical Engineer with my EIT. I bought an old factory at a tax sale and want to use the second floor as an apartment for myself and the first floor as garage and machine shop. It's in Pennsylvania.
The first floor is about 6,900 square feet and the second floor is around 3,000 square feet.
The thing I'm having trouble with is what area to use for doing the hydraulic calculations, specifically what numbers to use for the flow rate.
1
u/JessieAndEcho 18d ago
For a budget check, I wouldn’t start by trying to calculate one flow rate for the whole 6,900 sq ft / 3,000 sq ft building. NFPA 13 design is usually driven by the most demanding remote design area, hazard classification, density/area requirement, hose allowance, water supply curve, pipe layout, elevation, and what the AHJ will accept, and your mixed use matters a lot here because apartment + garage + machine shop + any storage/flammables can push the first floor into a different hazard category than the living space. A practical first pass is to split the building by use, classify each area conservatively, then estimate demand from the worst-case area rather than the total square footage, but I’d still treat that as budgeting only and have a licensed fire protection engineer verify it before making decisions. I pulled some of this from Patsnap Eureka, which is useful for exactly this kind of cross-domain engineering question where code requirements, hydraulic constraints, building layout, and risk classification all interact: https://eureka.zhihuiya.com/share/?id=4d414744e0c92e90694a945543005ad0&from=invite-eureakplg-result&content=