What are the Pros & Cons of Tankless vs. Tank Water Heaters?

On average, a standard water heater will need to be replaced after a decade. Some units may last longer with proper maintenance, and some may not last as long due to problems caused by extensive sediment build-up.

As a homeowner facing the need to replace your water heater, you may be wondering whether a tankless or traditional tank unit is best for your family’s needs. We’ve put together a list of the pros and cons for both types to help you make an informed decision for your household.

Tankless water heaters

What are they?

As their name suggests, they do not have a tank acting as a reservoir for hot water (as traditional units do). Instead, these efficient devices heat water very quickly and only when it’s needed.

Pros of tankless water heaters

  • The standard tankless unit may use 30-50% less energy than a traditional tank water heater since these devices only heat water when it’s needed.
  • Tankless models are compact and can often be installed in garages, closets, basements, or even outside the home in some areas.
  • Often, tankless water heaters will last longer than a standard unit, with some lasting twenty years or more.

Cons of tankless water heaters

  • Tankless units may be more expensive to install as they require special venting and retrofitting with your home’s electrical system. Additionally, if you need something bigger than the standard tankless size for your family’s water heating needs, you may have to purchase a larger, more expensive unit.
  • They might not supply enough hot water to support multiple water sources at the same time. For example, if someone is filling a bathtub with hot water, another member in your household running the faucet to wash dishes may not have enough hot water.

Who should buy a tankless water heater?

According to the U.S. Department of Energy, tankless units are most efficient for homes that use around 41 gallons or less of hot water each day.

Tank (traditional) water heaters

What are they?

Tank water heaters have a reservoir that holds hot water, ready for use when your family turns on the faucet, shower, washing machine, etc. These units are available in a variety of sizes, with the standard size having 40 to 50 gallons in holding capacity. They use natural gas, electricity or propane as their energy source.

Pros of tank water heaters

  • Installation costs for tank units are generally less than those of tankless models.
  • Often, tank water heaters can be set up without any special venting or changes to your home’s electrical system.
  • With a tank water heater, you will have a supply of fresh hot water ready for use in case of an emergency.

Cons of tank water heaters

  • Tank water heaters can’t be installed outside the home since they aren’t built to tolerate harsh weather conditions.
  • On average, traditional units don’t have as long of a lifespan when compared to tankless units.
  • When tank units are malfunctioning or about to “go out,” they may leak water and cause damage to items in the area where they’re installed.
  • Standard water heaters use more energy than tankless models because they are designed to keep a certain volume of water at all times.
  • If your family uses all the water in the tank, you’ll have to wait for it to fill up and heat more water.

Who should buy a tank water heater?

These water heaters are ideal for homeowners who currently have a water heater that runs on electricity. The standard home has an electric capacity of 200 amps and, often, tankless units will require extensive changes to your existing electrical system. Simply replacing your existing electric water heater with a comparable unit may save you time and money.

Also, if your family requires a lot of hot water for showers, washing clothes, doing dishes, etc., a standard water heater may be your best option as they keep a supply of hot water ready for use. According to ENERGY STAR®, if your home uses 86 gallons or more of hot water each day, a traditional unit is best for your family.

Which water heater is best for my home?

To determine which water heater is best for your family’s needs, consider how much hot water your household uses on a daily basis. A tankless unit may not be practical if your family uses over 86 gallons of water each day.

Also, consider what will be required for installation. A tankless unit may require retrofitting in your home, and this can get expensive. However, if you’ve been living with a traditional water heater with only two people living in your home, the upfront costs of installing a more compact tankless model may eventually save you money in the long run.

Finally, consider your spending budget. A professional will be able to work with you and your budget to help you calculate what capacity water heater you need as well as what will be the most efficient option for your household.