Continuous flow (tankless) hot water installation in NZ costs $1,800–$4,500. Electric units run $1,800–$2,800 installed; gas units cost $2,200–$4,500. The unit itself is $500–$2,500 with labour making up the rest.
A continuous flow system heats water on demand — no tank storing hot water. When you turn on the tap, cold water flows through a heating element (electric) or burner (gas) and comes out hot almost instantly. The main benefit: you can never run out of hot water, even with multiple showers simultaneously.
Continuous flow has higher upfront cost but can be more efficient with no standby heat loss. However, electric continuous flow units draw very high peak power (15–25kW), which can cause issues with older Christchurch wiring. Gas continuous flow is more practical for high-demand homes.
Works well for: multiple bathrooms used simultaneously, homes with gas connections, and properties where space is limited. May not suit older homes without adequate wiring (electric models) or homes without gas. Always consult your plumber about your specific setup.