What size water heater do I need?
Estimate peak-hour demand from showers, laundry, dishwasher use, and sink use before comparing tank, tankless, and heat pump options.
Homeowner utility
Start with the simple lifetime ownership calculator, then use the advanced calculator when you want to tune ZIP code, fuel setup, venting, access, water quality, and energy assumptions.
Three inputs: people, bathrooms, and years in the home. Compares standard tank, condensing tankless, and efficient heat pump tank by total ownership cost.
For detailsTune installation complexity, utility setup, venting, water quality, fuel price, temperature rise, and efficiency assumptions.
Quick guideSkip the calculator and scan scenarios where tankless can beat standard tank replacement on ownership cost.
Homeowner guides
Plain-English guides that help you size a system, compare equipment types, and ask better questions before getting quotes.
Estimate peak-hour demand from showers, laundry, dishwasher use, and sink use before comparing tank, tankless, and heat pump options.
Explain why tankless only wins in some long-horizon scenarios, especially when a standard tank would need a second replacement.
Use ENERGY STAR UEF data, rebate discussion, location constraints, and install-cost caveats.
Permits, disposal, expansion tank, pan, drain, venting, gas line, condensate, electrical, warranty, and maintenance.