Heating & Cooling

Drainwater Heat Recovery

Heating water accounts for up to 20 per cent of a home’s energy use, making it the second-highest energy consumer after space heating.

Drain-water heat recovery systems capture the heat from water going down a drain, typically the shower, and use it to heat cold water entering your water heater. It’s particularly effective when there are simultaneous water flows i.e. when you’re using hot water in the shower at the same time that water is flowing down the drain.

Things to Consider

  • Look for an ENERGY STAR® certified product. Drain water heat recovery systems can be purchased through your local plumber, a plumbing wholesaler, or online.
  • Drain water heat recovery systems are recommended for homes with higher than average hot water consumption (usually three or more people). The savings are greatest when all occupants take showers.
  • These systems typically last 30 years or more. The technology is simple and long-lasting, with no moving parts.
  • Hire a licensed plumber to install the system. It most cases, the installation will take a couple of hours.
  • Consider getting a home energy evaluation to help you understand how your home uses energy and identify all improvement opportunities.
  • Check with your municipality, utility or retailer to see if rebates are available.


$550 – $1,700 plus installation.

Source: Natural Resources Canada