Q: What does the State of Washington Energy Code give points for Hot Water systems?

A: The code provides points for different types of systems.

1/2 a point can be earned for using a gas, propane or oil-fired furnace with a minimum EF of .62. Electric water heaters need a minimum of .93. Energy Factor (EF) is an annual measure of the useful energy coming out of your water heater divided by the amount of energy going into your water heater to heat the water. The higher the number the better. For either situation you must have all showerheads and kitchen faucets shall be rated at 1.75 gallons per minute (GPM) or less. All lavatory faucets shall be rated 1.0 GPM or less.

One and 1/2 points can be earned for gas, propane or oil water heater systems with an EF of .82 or better. Solar water heating supplementing a minimum standard water heater will also qualify. Its rating system must be a minimum of 85 therms or 2000 kWh based on the Solar Rating and Certification Corporation Annual Performance of OG-300 Certified Solar Hot Water Heating Systems. Electric heat pump water heater with a minimum EF of 2.0 and meeting the standards of Northern Climate Specifications for Heat Pump Water Heaters. Water heated by a Geothermal heating and cooling system will also qualify.

Plumbers are well versed in the standard hot water tanks and tankless systems. The HVAC guys are now installing electric heat pumps that include heating hot water and the Geothermal systems that will also heat hot water.

Remember, small homes (<1500 sq.ft.) you need .5 points, Medium sized homes (1501 to 4999 sq. need 1.5 points and large homes (greater than 5000 sq.ft.) need 2 points.


Please submit questions to jon@quailhomes.com Jon can be reached direct at 360.907.5800. Tune into Green Building with Jon Girod on 1550 a.m. on Saturdays at 9 am. See you next week!