National ranges, by type
Fixr's 2026 installed ranges, as published (Fixr):
- Tank water heater: $600 to $2,500
- Tankless: $1,000 to $4,000
- Heat pump (hybrid): $1,200 to $4,600
- Labor: typically $300 to $1,500, between 18% and 50% of the total
- Permit: varies by location, $25 to $1,500 nationally
The lines on an itemized estimate
A complete estimate lists each of these, and leaves off the ones your house does not need:
- The water heater: brand, model, fuel and size (or flow rate for tankless). The biggest single line.
- Removal of the old unit: draining, disconnecting and taking it out of the house.
- Haul-away and disposal of the old unit.
- Expansion tank, where the water system needs one (see below).
- Relief valve discharge pipe, run to within 6 inches of the floor.
- Drain pan, where a leak would damage the room.
- Gas shutoff and sediment trap on gas units.
- Vent connector, and a liner or vent change if the chimney is unsuitable.
- Water connections: shutoff valve and connectors.
- Gas line or electrical work when the new unit needs more than the old one had.
- Permit and inspection, where the jurisdiction requires one.
Code items older houses are often missing
Northern Virginia follows the 2021 Virginia Residential Code. Three requirements account for most of the extra lines on an older house (VRC chapter 28, chapter 29):
- Relief valve discharge (P2804.6.1): the temperature and pressure relief valve's pipe must run full size, through an air gap in the same room, ending not more than 6 inches above the floor. Old installations often stop short or reduce the pipe size.
- Expansion tank (P2903.4.2): where a check valve, backflow preventer or pressure-reducing valve closes the water system, thermal expansion raises pressure, and a device to control it is required. Many homes have a pressure-reducing valve at the meter.
- Drain pan (P2801.6): a tank installed where a leak would cause damage sits in a pan. On a replacement, a pan drain is not required where none was installed before.
Venting and the chimney check
A gas tank that vents into a chimney it shares with the furnace is common in houses built before 1980, which is half or more of the housing in Arlington, Alexandria, Falls Church and the City of Fairfax (Census ACS 2020-2024). If the furnace has been replaced with a high-efficiency model that vents through the wall, the water heater can be left alone in a chimney too large for it, and it may not draft properly. A liner or a different vent is then a line on the estimate.
Arlington and Fairfax County require a Chimney Vent Certification whenever a fuel-burning appliance is replaced, confirming the vent is sized to code and clear (permit guide).
Permits: the published fees
Replacing a gas or oil-fired water heater always needs a permit in Virginia (13VAC5-63-80). Published fees read on October 7, 2026 ("about" figures are our arithmetic from the schedules):
- Loudoun County: $70 plumbing and $70 gas (one- or two-family home), two inspections included
- Fairfax County: $78.75 for one appliance plus a 2% levy and 10% surcharge, about $88
- City of Falls Church: $91.50 fuel-gas permit for a water heater replacement
- City of Alexandria: $95 minimum plus administrative, permit center, IT and training fees, about $124 before the state levy
- City of Fairfax: gas plus plumbing permits for a gas unit, about $200
- Arlington County: $139 base plus $57 per gas appliance plus a 2% levy and 10% surcharge, about $220
When the type changes
Switching from a tank to tankless usually adds a larger gas line, a vent through an outside wall, a condensate drain, an outlet and isolation valves for flushing. Those lines, not the unit, are why conversions cost more than like-for-like swaps; see tankless installation.
Switching to a heat pump from an electric tank is usually a close swap; from a gas tank it adds a 240-volt circuit if one is missing, a condensate drain, and capping the gas line. See heat pump installation.
Comparing a retailer quote with a local installer's
Big-box retailers sell installation as a package with the unit. Before comparing that price with a local installer's, check what the package includes and excludes: the permit and its fee, an expansion tank, the relief valve piping, a drain pan, haul-away, any venting or gas line change, and what happens if the existing setup does not meet code. Ask for each in writing.
An itemized estimate makes this comparison possible. A single number does not.
Why a replacement can cost more than you expect
It is rarely the unit. It is the house: a vent that no longer suits the appliance, a missing expansion tank on a closed system, relief piping that never reached the floor, an attic or closet location that is harder to work in, or a type change. Each of these is real work, and an estimate that names them lets you see exactly where the money goes.
Tell us the fuel, size and age of your current water heater and where it sits, and we can say which lines apply before anyone visits. Get an itemized estimate.