Traditional vs. Tankless Water Heaters

On a scale from cold coffee to world hunger, running out of hot water is most definitely toward the first-world-problems end of the spectrum. Still, that doesn’t make the experience any less frustrating or any more comfortable. Even the morning-person-est of morning people is likely to scream a swear word or two when the shower turns to sleet. It’s pretty much the worst wake-up call imaginable.

If you’ve had it with cold showers and you’re thinking your water heater is to blame, you’re probably right. And if you’re thinking a tankless, or on-demand, water heater might be the perfect solution to your problem, you might be right. As Pittburgh’s most-trusted plumber, we can help you make an informed decision about your water heater. As with most things homeownership, you’ll need to weigh several factors before making the switch from traditional to tankless.

What is a Tankless Water Heater?

As the name implies, tankless water heaters don’t store hot water. Instead, they have heated coils through which water is warmed on demand. When you turn on your shower, water runs through those coils, and you’re treated to an endless supply of hot water—theoretically, anyway. Keep reading.

Hot Water Capacity in Tankless and Traditional Water Heaters

Traditional water heaters, also called storage tank water heaters, hold between 20 and 80 gallons of hot water. When hot water is needed—by your dishwasher, for example—it’s carried through your pipes from the storage tank to that appliance. Then, cold water fills flows into the storage tank and is warmed over time. If you use hot water faster than the cold water can be warmed, you “run out” of hot water. So, if you’re consistently cussing at your shower, it’s likely your water heater is too small for your needs.

If that’s the case, does it make sense to just switch to an on-demand water heater instead? Not necessarily. While tankless water heaters don’t have the capacity problem of traditional heaters, they could pose a different problem: flow rate. Tankless water heaters can have trouble keeping up with simultaneous demands. If you’re running two showers and the washing machine at the same time, something (or someone) is going to suffer. To solve that problem, you can install multiple tankless heaters and enjoy a truly never-ending supply of hot water.  But that brings us to another point of comparison: cost.

Costs of Tankless vs. Traditional Water Heaters

According to Home Advisor, the average purchase and installation cost of a 40- to 50-gallon water heater is just shy of $900. To buy and install a tankless model can cost more than three times that—$3000 on average.

So is on-demand hot water worth it? From a comfort standpoint, yes. From a pocketbook standpoint? Maybe, maybe not. As reported by, tankless units don’t have the standby losses of traditional tanks, and they’re 8-34% more efficient and can last twice as long as storage tank models. Still, if cost is a concern, you should carefully weigh your initial outlay for purchase and installation against the savings you’ll enjoy over time.

Pros and Cons of Tankless vs. Traditional Water Heaters

Here’s an at-a-glance comparison of traditional and tankless water heaters.

Pros of Traditional Water Heaters

  • Relatively low up-front costs.
  • Simple and quick to install.

Cons of Traditional Water Heaters

  • Slightly higher utility bills because water is warmed regardless of your need for it at the time.
  • Takes up more floor space.
  • Hot water supply is limited by the storage tank capacity.
  • Life expectancy of 10-15 years.

Pros of Tankless Water Heaters

  • Smaller units that can be installed anywhere.
  • Deliver up to three gallons of hot water per minute. (See Cons!)
  • Life expectancy of 20+ years.

Cons of Tankless Water Heaters

  • Higher up-front costs.
  • Can take more time to install.
  • Deliver up to three gallons of hot water per minute—which is adequate unless you’re running multiple appliances at once.


Still Not Sure Which Water Heater is Right for You?

We hate cold showers, too, and we’re happy to help! Give us a call today and we’ll talk through your household size and habits so you can make the best decision for your family.

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