Tankless vs Tank Water Heater in Boise

Debating which type of water heater to get?

Both types of water heaters have their pros and cons—so there’s not always an obvious winner.

That said, choosing the right water heater for your home depends on the following factors:

  1. Your budget
  2. Your available space
  3. How many hot water appliances you run at once

In this article, we’ll go into more detail about each of these factors to help you get a better idea of what type of water heater you should get.

But first, let’s take a quick look at how each type of water heater works…

Want a recommendation on a water heater for your Boise home? We can help! We install both tank water heaters and tankless water heaters.

How tank and tankless water heaters work

Tank water heaters use natural gas burners or electric heating elements to heat water, and like their name suggests, they store the hot water in a tank until it’s needed. Residential tank water heaters can store anywhere from 30 to 80 gallons.

On the other hand, tankless water heaters use high-powered burners or electric heating elements to quickly heat water when you turn on the hot-water tap. This means a tankless water heater can deliver a “never-ending” supply of hot water.

Note: Although a tankless water heater doesn’t necessarily “run out” of hot water (it can supply hot water for an unlimited amount of time), it can only supply so much hot water at once. We’ll discuss this more below, when we talk about how many hot water appliances you run at the same time.

Now that you know a little bit about how each type of water heater works, let’s look at the factors that will help you choose which one to get.

Factor #1: Your budget

Generally, tankless water heaters will be more expensive to install than tank water heaters.

Here’s how each one breaks down in price:

However, when it comes to operational costs, tankless water heaters actually use 24% to 34% less energy, which means you’ll spend less on monthly energy bills.

That being said, studies have shown these savings are not likely to pay for a tankless unit’s higher upfront installation cost. One study estimated that a tankless system would have to last over 20 years to pay for the installation cost, and most tankless units start to die around the 20-year mark.

The bottom line?

Tank water heaters are going to be less expensive upfront than tankless units. However, tankless units will last longer and cost less to operate. You’ll have to consider which is more important to you: a low upfront cost (tank) or a longer-lasting, more energy-efficient system (tankless).

Factor #2: Your available space

Tank water heaters require a large storage tank, which takes up a lot of space.

On the other hand, tankless units are more compact, easily fitting inside a closet or cabinet. They can even be installed on an outside wall if you do not have sufficient space inside.

If you have limited space in your home to accommodate a tank water heater, the better option would be to go the tankless route.

Factor #3: How many hot water appliances you run at once

Do you often run hot-water appliances at the same time? (For example, your dishwasher, shower, washing machine, etc.)

If so, a tank water heater is probably your best option.


Even though a tankless water heater delivers a “never-ending” supply of hot water, it is limited by its flow rate. Flow rate measures how many gallons of hot water the unit can provide in a minute (gallons per minute, or gpm).

Each hot water appliance in your home also has a flow rate indicating how many gallons of hot water they use per minute.

Below are the average flow rates of a few hot-water appliances:

  • Kitchen faucet: 1.5 gpm
  • Shower: 2.5 gpm
  • Clothes washer: 2 gpm

If you wanted to run all of the appliances above, you’d need a tankless unit that can supply at least 6 gpm.

If you were to run more appliances and exceed your tankless water heater’s flow rate, you’ll notice a drop in water temperature.

On the other hand, tank water heaters can provide hot water up to the size of its tank, which ranges from 30 to 80 gallons. If your tank water heater is sized correctly for your hot water demands, that means you can run all of your hot-water appliances at once and not notice a drop in water temperature.*

*Note: A tank water heater can provide hot water to as many appliances as needed—but only until the hot water runs out. If you opt for a tank water heater, you’ll have to account for “recovery time,” which is the time it takes for the tank to fill back up and heat the water.

Want a free quote to install a water heater in your Boise home?

We’ll give you upfront and honest pricing on the cost to install a tank or tankless water heater for your home.

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