ROOF DRAINS

VERSION

V1

STATUS

Stable

STANDARD

NONE

DESCRIPTION

TESTING

Storm Drainage Runoff Calculator

Roof drainage · Florida Building Code — Plumbing, 8th Edition (2023). Enter the applicable design rainfall and roof area. Roof drains and scuppers receive preliminary size references without product data. Final inlet capacity and allowable water depth require design verification.

Project name

Client

Location

Project type

Rainfall source / design basis

Enter the applicable intensity in each zone. Location alone does not determine rainfall. Confirm the adopted edition and local requirements with the jurisdiction.

Roof drains / scuppers: preliminary estimates only. The stated required flow is the capacity to verify for the selected inlet at the permitted water depth. A reference pipe diameter or opening size does not establish inlet capacity. Collectors fed by these estimates remain preliminary.

Drainage Zones

Roof mode uses C = 1. Area is horizontal roof projection; enter applicable contributing wall area in the row details. Quantities assume equal flow distribution. Primary and secondary drainage remain independent. Displayed flows are rounded; selection comparisons use unrounded values.

Zone name / ID	C	I [in/h]	Roof area [ft²]	Total Q [gpm]	Qty	System type	Slope	Reference / status	Proposed selection	Act.

Combined Areas (Collectors / Mains)

Select contributing zones. Totals use unrounded runoff, not displayed values. A zone may appear in several independent checks; do not count a catchment twice in the same physical flow path.

Collector name	Contributing zones	Total Q [gpm]	Qty	System type	Slope	Reference / status	Proposed selection	Act.

Complete the inputs to calculate. Reports are unavailable while results are pending or invalid. Project inputs can be saved as a draft.