Fire Flow Calculator

How much water does the building need? Two classic pre-planning estimates — compare them and you'll see why "it depends" is the honest answer.

Method

National Fire Academy quick-calc for structural attack planning.

Building length (ft)

Building width (ft)

Percent involved

Floors involved

Typical line flow (for line count)

Turns the estimate into a deployment answer: how many lines like yours it takes.

Enter values above to see the result.

Reference flow targets (training discussion)

Structure	Reference flow
Single-family residential	300 GPM
Apartment	300 GPM
Strip mall	500 GPM
High-rise fire floor	500 GPM

Sanity-check your estimate against these common training targets — they are discussion anchors, not a determination for any specific building or department.