Estimate simultaneous fixture flow, determine required pressure increase, then confirm the pump curve reaches that operating point with margin.
Start with simultaneous demand
List the fixtures likely to operate at once. A shower, dishwasher and garden tap create a different peak demand than one bathroom used at a time.
Use realistic simultaneous flow rather than adding every fixture in the house.
Convert pressure into head
Pump curves are often expressed in metres of head. Roughly, 10 metres of water head is close to 1 bar of pressure.
The system must overcome elevation plus pipe friction and still deliver the target pressure at the fixture.
Check the source side
A booster cannot fix an inadequate supply indefinitely. Confirm inlet pressure, suction conditions and that the source can provide the required flow.
For tank or rainwater applications, suction depth and priming architecture matter.
Why variable-speed pumps are useful
Variable-speed systems such as DAB Esybox adjust motor speed as demand changes, helping maintain more constant pressure and reducing unnecessary full-speed operation.
That convenience comes with higher electronics complexity and purchase cost.