Total Dynamic Head (TDH) Calculator

Size pool and spa systems the way permitting authorities expect. Enter pool dimensions and piping — we auto-look up friction losses, recommend pipe sizes, flag velocity issues, and return the simplified TDH per the ANSI/PHTA/ICC-7 worksheet.

Inputs

Pool

Surface area (sq ft)Average depth (ft)Turnover time (hours)Feature demand (GPM)Spillways, waterfalls, etc.

Spa (optional)

Number of jetsGPM per jet

Piping

Suction pipe sizeSuction length (ft)Return pipe sizeReturn length (ft)

Equipment losses

Filter loss (ft)From filter data sheet, PSI × 2.31 = ftHeater loss (ft)Other losses (ft)Fittings, valves, elevation, etc.

Results

System designed for

27.4 GPM @ 14.2 ft TDH

Pool volume

9,873.6 gal

Turnover

360 min

Pool flow

27.4 GPM

System flow (pool + feat.)

27.4 GPM

Spa jet flow

0 GPM

Design flow

27.4 GPM

Recommended pipe sizes at design flow

Branch (≤6 fps): 1.5"
Trunk (≤8 fps): 1.5"
Return (≤10 fps): 1.5"

TDH breakdown

Suction (2", 60 ft × 0.027 ft/ft): 1.62 ft · 2.65 fps
Return (2", 70 ft × 0.027 ft/ft): 1.89 ft · 2.65 fps
Piping total: 3.51 ft
Filter: 0.7 ft · Heater: 10 ft · Other: 0 ft
Total TDH: 14.2 ft

Values within simplified TDH velocity limits.

Preliminary estimate per ANSI/PHTA/ICC-7 2020 & APSP/ICC-15 2011 simplified method. Not a substitute for a signed and sealed engineering worksheet. Contact Golden Key Developments for a stamped submittal.

Need a signed & sealed worksheet?

Golden Key Developments prepares stamped TDH submittals for permit review. Share your project and we'll get you a signed worksheet.

Contact Golden Key Developments