Customer Service Hours:
(319) 268-5280
M-F: 7:30 a.m. - 5:30 p.m.

Sat & Sun: Closed

Help Desk Hours:
(319) 268-5221
M-F: 7:30 a.m. - 9 p.m.
Sat & Sun: 9 a.m. - 5 p.m.


Build a 5-Star Home

CFU 5-Star Home Program

**Effective February 2014, the 5-Star Home Program has been integrated into our residential rebate program. Visit the rebate page and select New Construction Insulation and Air Sealing for details.

Old 5-Star program:

Equipment     CFU-Certified 5-Star Standards
  • Central air conditioner must be minimum 16.0 SEER
  • Ground-source heat pump (open or closed loop) must be minimum 16.2 EER
  • Programmable thermostat required
  • Natural gas forced-air furnaces must have minimum 95% AFUE and ECM motor
  • Natural gas boiler must have minimum 92% AFUE
  • Ground-source heat pumps (open or closed loop) minimum COP of 3.3
  • Programmable thermostat required
Duct Sealing
  • Sheet metal joints sealed with mastic or UL-181 approved tapes
  • All low-pressure supply and return ducts sealed
  • 0.25 natural air changes per hour
  • Air-to-air heat exchanger (heat recovery ventilator or energy recovery venitilator)

      Refrigerator (ENERGY STAR)
      Clothes Washer (ENERGY STAR) 
      Dishwasher (ENERGY STAR)

Lighting       Recessed Can Lights (LED or CFL)
  • Attic insulation minimum R-50
  • Floor insulation above unconditioned space minimum R30
  • Wall insulation (wood frame walls) R20 minimum cavity
  • All other applicable insulation as required by IECC 2009
Water Heater

Natural Gas (.67 Energy Factor or greater)

Electric (.93 Energy Factor or greater)

Windows 0.35 U-value or less