Tank vs tankless, without the sales pitch
Tankless is better at some things and worse at others. Which matters depends almost entirely on how much hot water your household uses at once, and on what your house needs before a tankless unit can be fitted at all.
| Storage tank | Gas tankless | |
|---|---|---|
| Typical installed cost | $1,600 to $3,100 | $3,200 to $8,000 |
| Runs out of hot water | Yes, once the tank is drained | No, flow rate is the limit instead |
| Two showers at once | Depends on tank size | Yes, if sized properly |
| Floor space used | Roughly the footprint of a bin | Wall mounted, frees the floor |
| Gas line work likely | Rarely on a like for like swap | Often, and it is expensive |
| New venting needed | Usually reuses existing | Almost always |
| Annual maintenance | Flush occasionally, easy to neglect | Descaling matters, more so in hard water |
| Expected life | 10 to 13 years | 15 to 20 years if maintained |
| Emergency replacement | Same day is realistic | Permits and parts take longer |
Storage tank
- Typical installed cost
- $1,600 to $3,100
- Runs out of hot water
- Yes, once the tank is drained
- Two showers at once
- Depends on tank size
- Floor space used
- Roughly the footprint of a bin
- Gas line work likely
- Rarely on a like for like swap
- New venting needed
- Usually reuses existing
- Annual maintenance
- Flush occasionally, easy to neglect
- Expected life
- 10 to 13 years
- Emergency replacement
- Same day is realistic
Gas tankless
- Typical installed cost
- $3,200 to $8,000
- Runs out of hot water
- No, flow rate is the limit instead
- Two showers at once
- Yes, if sized properly
- Floor space used
- Wall mounted, frees the floor
- Gas line work likely
- Often, and it is expensive
- New venting needed
- Almost always
- Annual maintenance
- Descaling matters, more so in hard water
- Expected life
- 15 to 20 years if maintained
- Emergency replacement
- Permits and parts take longer
The number that decides it
Most comparisons stop at the price of the appliance, which is the least useful figure available. A tankless unit is frequently the cheapest line on a tankless quote. The expensive parts are the gas line, the venting, the dedicated circuit and the condensate route, and none of them appear until a contractor has looked at your house.
So the real question is not what tankless costs. It is what tankless costs in your house, and that number varies by several thousand dollars between two homes on the same street.
Who should genuinely go tankless
- Households where showers, laundry and dishes regularly overlap
- Homes where the existing gas line is already adequate
- Anyone whose unit sits outside or on an exterior wall, which cuts the venting cost
- People who plan to stay long enough to see the longer life pay off
Who should not
- One or two people who rarely run two hot taps at once
- Homes that would need a gas line upgrade to support it
- Anyone replacing a failed heater today, where the conversion time is a real cost
- Households that will not keep up with descaling, particularly in hard water
Not sure a heat pump belongs in the conversation? In most Central Valley homes it is the cheapest option to run, which makes it worth understanding before you commit.