Stories & Features

Hot water tips, from the tank to the tap

Image of water flowing from a shower head
After space heating, water heating typically uses the most energy in your home. Getting it right is key for savings - and for safety.

Save on hot water heating while ensuring safety and efficiency in the home

For most of us, water heating is one of the biggest energy users in your home. So it makes sense to ensure you're being as efficient as possible with your hot water heater, and making smart choices around your hot water use, so that you can find savings throughout the year.

We've consulted BC Hydro engineer Gary Hamer for a list of things you should know to ensure both hot water efficiency and safety:

1. Temperature at the tank (60°C) and tap (49°C) are two different things

Your water needs to be just hot enough to ensure bacteria can't form, yet not so hot that energy is wasted and you run the safety risk of scalding skin at the tap or in the shower. That's why it's vital to follow the BC Plumbing Code-mandated temperature of 60°C at the tank, and no higher than 49°C at the tap.

Ideally, every fixture in your home would be equipped with a mixing valve that would ensure a tap temperature no higher than 49°C. But Hamer says that for many, it's easier to rely on a mixing valve at the hot water tank.

"The reality is that nobody is going to tear their wall apart to put in a valve," says the BC Hydro engineer. "In new construction, installing anti-scald valves near taps is a great idea, especially for families with young children. But it's easiest to put in valves at the water heater. Speak with your heating contractor about putting in an anti-scald or mixing valve at your water heater location."

2. Favour showers over baths, and limit them to five minutes

There's no easier way to save on hot water-related energy costs than to choose showers over baths, as a bath can use three to six times as much hot water as a five-minute shower. But shower length is the key. If two people in your home cut their shower time by a minute each, you could save $30 on energy costs over a year. Cut showers by two minutes, and you could save $60.

3. Fix that leaky tap

It's easy to put off fixing a leaky tap, but that steady drip adds up. Fixing a hot water leak in your faucet can save up to $9 per year in energy costs.

Here's how to fix that leak.

4. Wash clothes in cold water

By switching from hot to cold water for an average of three loads per week, you could save up to $22 per year on your energy bill.

5. Turn off the tap while brushing teeth, shaving

A couple good things happen when you turn off the tap while brushing your teeth. One, you save water. Two, you're more likely to actually brush more carefully and longer than you would if you left the water running. This can work wonders with reluctant kids and teens. Ditto for those who are shaving. Fill part of the sink with hot water instead of letting the water run, and take the time to fix your sink stopper if it's leaky, as you won't need to keep refilling the sink.

6. Wash as many dishes as possible in the dishwasher

It can be therapeutic to do the dishes, but other than big pots that don't fit in the dishwasher (and pans that require scrubbing), let the dishwasher do the work instead. Handwashing dishes uses more water.

7. Right-size your hot water tank

You'll waste energy with a 60-gallon tank if a 40-gallon tank is enough to meet your household needs. Just be careful to avoid going so small in the name of efficiency that you drain your tank regularly and damage your tank through "thermal shock", caused by expansion and contraction of your tank when it's refilled with cold water too often. "If your tank goes through those cycles a lot, it's going to fail early," says BC Hydro's Hamer, whose family once rented a home in which the hot water tank failed twice in three years. "if you find you're draining your tank, you need a bigger size tank."

8. Electric? Gas? Consider a heat pump hot water heater

If it's time to replace your hot water tank, or you're building a new home and trying to decide which type to get, there are a few factors to consider. The size of your home, number of occupants and your typical water use are important in deciding which tank type and size are right for you.

Storage tanks are the most common type in Canada and come in gas or electric models. Have a chat with your heating contractor about the practicalities, and the pros and cons, of going with electric vs. gas, storage tank or tankless. And consider using BC Hydro's home renovation rebate of up to $1,000 for the purchase and installation of an electric heat pump hot water heater. Unlike heat pump space heaters, heat pump hot water heaters aren't weather dependent, and can be used effectively in any part of B.C.

9. Tankless heaters work best in smaller applications

If you've been considering a tankless option for your water heating, they're currently only available in gas models. ENERGY STAR® versions are much more efficient than a standard storage tank, but the suitability of this "on-demand" water heater will depend on how much hot water is needed. Tankless water heaters, popular in cabins and smaller homes, may not have the capacity to supply an entire home with hot water.

FortisBC offers rebates on qualifying tankless water heaters, and has excellent information on the pros and cons of going tankless. Note that tankless models cost more up front than storage tanks and can have higher installation costs.