What’s the difference? Compare the ENERGY STAR® Northwest home against standard Idaho code-built homes and see for yourself! Individual ENERGY STAR home requirements may vary.

Feature Idaho Code ENERGY STAR
Wall Insulation R 13 or 19 R19 or R211
Floor Insulation R30 R30
Attic Insulation R38 R38 or greater
Windows Class 35 Class 352 or less
Doors Standard Insulated
Ventilation Standard bath fan Quiet fan rated for continuous operation
Ducts R6 insulation R8 insulation, duct leaks sealed and inspected
Gas Furnace 80 Percent AFUE 90 Percent AFUE3
A/C Unit SEER 13 SEER 134
Heat Pump 6.8 HSPF 8.5 HSPF5
Gas Water Heater 58 Percent EF 61 Percent EF
Electric Water Heater 80 Percent EF6 93 Percent EF
  1. The “R-Value” of insulation is a measure of its resistance to heat flow. The higher the R-value, the greater the insulating effectiveness.
  2. Class 35 windows refer to a U-Factor of .35 or less. Use the U-factor to compare not only the window's energy efficiency, but its construction quality as well. Windows with a U-factor of 35 are “low-e” for low-emissivity. These windows are manufactured with thin metal coatings that keep thermal energy in while blocking harmful rays that can fade carpets and furniture.
  3. Annual Fuel Utilization Efficiency (AFUE). Developed by the U.S. Department of Energy, the AFUE indicates what percent of the energy used is converted to useable heat. The higher the AFUE, the more efficient the furnace.
  4. Seasonal energy efficiency ratio (SEER) is the amount of cooling your equipment delivers per every dollar spent on electricity. The higher the SEER value, the more efficient the equipment.
  5. Heating Season Performance Factor (HSPF) . This test attempts to take into account the reductions in efficiency caused by defrosting, temperature fluctuations, supplemental heat, fans and on/off cycling. The higher the HSPF, the more efficient the heat pump.
  6. Energy Factor (EF). Water heater efficiency is reported in terms of the energy factor (EF). The higher the EF, the more efficient the water heater.

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