This ESP version of the Insul-Tec picture window is another great choice ESP = Energy Save Package. Simply a great maintenance free picture window that stands up to the test of time. When considering replaceing any window take the time to compare ratings, installation experience, guarantees, reviews and testimonials. We know you have choices and believe once you take the time to see the options you will be glad you called Wonder Windows.

  • 10% Better than Energy Star┬« minimum
  • 3000% Better AI protection
  • Full 3┬╝" Depth Welded Mainframe 
  • Excellent craftsmanship
  • Vinyl windows are strong and durable 
  • Foam filled frame for greater performance
  • Beautiful, and strong for years of long lasting maintenance free performance.
  • Heatseal┬« warm edge spacer system drastically reduces the possibility of condensation on the inside of the window.
  • Available in Replacement and New Construction applications.
        Energy Star                                                                                                                                                Comparison To
Glazing Option U-Value SHGC VT CR Minimum* Energy Star Minimum
Dual Glazed              
With ESP 0.27 0.31 0.56 64 0.30 10% Better
    Industry Comparison To  
  OKNA Windows Minimum Industry Minimum  
AAMA Rating   R75 R15      
Air Infiltration cfm/ft2 <0.01 0.3 3000% Better
Water Penetration mph     66 33   100% Better  
Structural Integrity mph   210 94   123% Better