Fire Hydrant Network (Loop / Single Line)

External fire hydrant network point by point: design values from KMK 2.04.02 / SP 8.13130, NFPA, DVGW W 405 or the Turkish regulation, loop or single line, friction per standard, local losses fitting by fitting, automatic worst case, residual pressure at every hydrant, required supply / pump pressure and take-off.

1 · Standard and design values

Standard

System

Basic fire protection (DVGW W 405)

Building hazard class (BYKHY)

Region risk (hydrant spacing, Madde 95/3)

Building (ShNQ 2.04.02-19 Table 7)

Number of floors

Building volume (thousand m³)

Total fire flow (L/s)

Simultaneous hydrants

Flow per hydrant (L/s)

Fire duration (h)

Minimum pressure at the hydrant (m)

Highest point of the building (m)

Hose diameter

Hose resistance S (per 20 m) ShNQ 8.16⁶ formula: h = 0.00385·q² per m (S = 0.077)

Hose length (m)

Nozzle pressure (m)

2 · Pipe and line

Pipe material

SDR

Main size (OD mm)

Friction formula

Line type

Start point (supply tee)

Ground level at the supply tee (m)

3 · Points in order from the supply tee

#	Point	Distance from previous (m)	Ground level (m)	Elbow 90°	Elbow 45°	Elbow 22.5°	Valve	Hydrant	Branch L (m)	Branch Ø	Branch 90°	Branch 45°	Branch valve	Outlet height (m)	Main Ø (if different)
↩	Back to start

Distance = pipe length from the previous point (the first point: from the supply tee). Elbows and valve = fittings on that pipe. For a hydrant point the tee is on the main and the branch leads to the hydrant; branch Ø empty = main size. Outlet height = hydrant outlet above ground (0 for underground hydrants).

Schematic

Numbers follow the table rows - check the order here. Red = hydrant, filled red = active in the worst case.

4 · Supply

Supply pipe size

Supply pipe length (m)

Level of the pump / city connection (m)

Calculate

Available pressure at the supply (m)

Worst case search

⚙️ Local loss coefficients and limits

K elbow 90° (-)

K elbow 45° (-)

K elbow 22.5° (-)

K isolation valve (open) (-)

K tee, straight through (-)

K tee, into the branch (-)

Maximum velocity (warning) (m/s)

Water temperature (°C)

Hazen-Williams C (-)

Pipe roughness (mm)

🚒

Fire Hydrant Network

Step 1 - design values
• Choose the standard: KMK 2.04.02 / SP 8.13130 (low- or high-pressure system), NFPA (IFC Appendix B/C, NFPA 24), DVGW W 405 or the Turkish regulation.
• Suggested simultaneous hydrants, flow per hydrant, duration and minimum pressure can be changed - changed values are marked as user input in the report.
• High-pressure system: Hmin = building height + hose loss (L/20·S·q²) + nozzle pressure.

Step 2 - points
• Start = supply tee. Each point: distance from the previous point, elbows, valve, ground level.
• Hydrant point: branch length and size, branch elbows and valve, outlet height.
• Loop: the last point joins the start. Paste the rows from Excel.

Hydraulics
• Gradient (Newton) solver - loops without manual flow split.
• Local losses fitting by fitting at each pipe's own velocity.
• Worst case automatically; residual pressure and velocity everywhere; required supply pressure or check of the available pressure.

Key Points:

KMK 2.04.02, SP 8.13130, NFPA, DVGW W 405, Turkish regulation
Loop or single line, point by point
HDPE PE100 by default - PE80, PVC, steel, ductile iron
Friction per standard: KMK formula, Hazen-Williams, Darcy-Weisbach
Local losses fitting by fitting
Worst case found automatically
Numbered live schematic
Take-off: pipes, tees, elbows, valves, hydrants
PDF and CSV report

Calculation Steps:

Enter all required parameters
Click "Update Calculation"
Review results and analysis