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Water heater cost calculator

The quoted price for a water heater is never the price of the water heater. It is the unit, plus the hours, plus the four small lines that turn a swap into a code-compliant installation. This builds the number the way an estimator does — one line at a time, each one a range, with your own shop rate on the labour.

How the price is built

Two lines carry most of the number. The unit is a retail band for the class — a 50 gallon gas tank spans roughly $750 to $1,500 depending on warranty length and brand tier, and a heat pump unit is two to three times that. Labour is hours times your rate, and the hours are the honest part: a like-for-like swap in an accessible garage is three, the same unit in a second-floor closet with a pan and a new flue is five or more.

The remaining lines are small individually and decisive together. Skip the expansion tank on a closed system and the job fails inspection. Skip the pan above a finished ceiling and the first leak is a claim.

A band is not a quote

Nothing on this page prices your specific job. Price the unit at your supplier the day you quote, put your own hours on it, and look up the permit fee for the jurisdiction.

The two lines that blow the budget

Going from a tank to a tankless is where a swap becomes a project. A whole-house gas tankless commonly needs a larger gas line — see the gas pipe size calculator — and a different vent, in stainless or PVC depending on the unit. Either can add more than the appliance cost. Read both before you promise a number.

The other one is access. A unit that cannot come out the way it went in is a demolition line nobody quoted. Measure the doorway.

Code notes

IPC 607.3 Thermal expansion control is required where a backflow preventer or pressure-reducing valve makes the system closed. IPC 504 covers the relief valve and its discharge piping. Most jurisdictions require a permit for a water heater replacement; confirm with your authority having jurisdiction (AHJ).