Question 1

What is Total Dynamic Head (TDH) and why does it matter for sump pumps?

Accepted Answer

Total Dynamic Head (TDH) is the sum of the vertical lift (elevation gain) and the friction loss caused by the water flowing through the pipes, elbows, and valves. It is the most critical metric in choosing a sump pump because a pump's ability to move water decreases significantly as the head increases.

If you ignore TDH, you risk choosing a pump that cannot handle the resistance of your specific plumbing configuration, leading to slow water removal, overheating, and premature pump failure. Calculating this value accurately ensures your system operates within its efficiency curve.

Question 2

How do pipe diameter and pipe length affect sump pump performance?

Accepted Answer

Pipe diameter and total run length are the primary contributors to friction head loss. Smaller diameter pipes create significantly more resistance for water to travel through, which effectively reduces the pump's performance capacity. Conversely, larger pipes decrease friction but can increase the volume of water that backflows into the pit when the pump cycles off.

Our tool uses standard Hazen-Williams principles to estimate these losses based on common pipe materials like PVC or galvanized steel. By inputting your specific pipe run configuration, you can see exactly how much pressure is being lost, allowing you to optimize your system for better flow rates.

Question 3

What is the recommended Gallons Per Hour (GPH) for a typical home?

Accepted Answer

For most residential basements in moderate climates, a standard 1/3 HP to 1/2 HP pump is sufficient, typically providing between 2,500 and 4,000 GPH at 10 feet of head. However, homes in areas with high water tables, frequent heavy rainfall, or larger square footage may require higher capacity pumps to keep up with the inflow rate.

To determine the correct GPH, you should estimate the inflow rate during a storm event and ensure your chosen pump can clear that volume at your calculated TDH. Never rely on the 'maximum GPH' advertised on the box, as that value is usually calculated at zero feet of lift, which is almost never the reality in a functioning home system.

Question 4

Does this calculator save my data to my computer?

Accepted Answer

No, this tool does not save or store any data on your device. It operates entirely within your browser's active memory for the duration of your session. When you refresh the page or close your browser, all inputs and calculations are cleared for your privacy and security.

This architecture is intentional to ensure compatibility with strict sandbox environments and to respect user privacy. You can perform as many calculations as you need, and the system will remain clean and ready for the next user without tracking or data persistence.

Free Sump Pump Head Lift & GPH Sizing Calculator