Traditional vs. Tankless Water Heaters

Water Heater

If you’re considering upgrading or replacing your home’s water heater, you probably already know you have many options. It’s common to have questions about which type of water heater is going to perform best while saving the most money on energy bills. Of course, you also want a unit that requires the fewest number of future repairs. Each home’s situation is different, so there isn’t a catch-all solution. Rather, it’s best to weigh the pros and cons and decide for yourself which type of water heater will better suit your needs.

Traditional Water Heaters

You may already be familiar with traditional water heaters due to their prevalence in North America. Also called tank or storage water heaters, traditional water heaters are usually found in a utility closet or garage and feature a large storage tank capable of holding anywhere from 20 to 80 gallons at a time, depending on the size of the unit.

Powered by electricity, natural gas or propane, the unit cycles in cold water, heats it and stores it until hot water is used in the home. The process repeats as often as you use the sink, shower, dishwasher and other appliances.


Installing a traditional water heater is relatively inexpensive, costing just under $900 on average according to Home Advisor

  • Allows you to use hot water for several appliances simultaneously due to its large storage capacity
  • Installation is easy and affordable
  • Technology has been used and relied on for over 100 years1


  • Constantly uses energy to maintain the temperature of water in the tank, called “standby loss”
  • Takes up a lot of otherwise useful storage space
  • Often requires over an hour for more hot water to be cycled in again after tank is emptied
  • Shorter lifespan of approximately 10 years on average2

Tankless Water Heaters

The biggest difference between traditional and tankless water heaters is tankless water heaters are, well, tankless. Rather than storing hot water in a large reservoir until it’s used, tankless water heaters supply hot water on demand. When you turn on your shower, for example, a tankless water heater activates and cycles cold water through a small heating element and sends it to your showerhead for only as long as the hot water spigot is open.

Tankless water heaters are powered by either electric or natural gas sources. Gas water heaters typically provide a higher flow rate than electric. On average, tankless water heaters can supply two to five gallons of hot water per minute.3


  • No standby loss so they operate with much better efficiency
  • Energy Star estimates $1,800 in energy savings over the lifespan of the unit2
  • Lifespan is longer, usually more than 20 years
  • Doesn’t rely on a reservoir so hot water is unlimited
  • Much smaller in size
  • Individual units can be installed throughout the home due to their small size


  • Home Advisor estimates the average tankless installation costs around $3,000, much higher than traditional installation costs
  • Often more difficult to install and may require installation of additional equipment
  • Limited flow rate does not adequately provide hot water when multiple applications are in use (dishwasher, shower and washing machine simultaneously, for example)
  • Requires more maintenance due to more advanced technology
  • Electric-powered systems are generally not powerful enough for whole-house water heating

Which Is Right for You?

Whether you choose a tank or tankless water heater depends on your personal needs. For households with tighter budgets needing a fast and easy replacement, a traditional water heater might be the way to go. Traditional water heaters may also be a better option for larger households, where multiple showers and appliances are frequently used simultaneously. It’s worth noting that newer tank water heaters are more efficient than older models, so you could still see energy savings with a traditional water heater.

However, if you’re more concerned about saving energy than upfront costs, a tankless water heater could be a smart investment. Tankless water heaters might also be a good option for providing hot water to a guest house or similarly small building.

No Matter Which Water Heater You Choose, Choose South West Plumbing

When you’re installing a new hot water heater in your home, it’s critical you work with trusted, certified plumbers so the job is done right. South West Plumbing provides tankless and tank installation for the Seattle area, and has done so for more than 35 years. For more information about installing a new, energy efficient water heater in your home, call or contact us online for more information today!