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Thermo-Fit® Double-Hung Replacement Windows

Looking for a window that slides up and down without a lot of effort? Want a traditional window updated for today's energy-saving and building requirements? Get it all with energy-efficient Thermo-Fit Double-Hung windows from Thermo-Tech. Learn more about Thermo-Fit custom replacement windows.

  • Top and bottom sashes tilt in for ease of cleaning.
  • Flush mounted tilt latches.
  • Smooth gliding balance system uses constant force coil that needs no adjusting and little or no maintenance.
  • Die-cast lock and keeper hardware draws in the sash for secure and weather tight locking.
  • Slope sill directs water runoff even in a driving rain.
  • Dual weather-stripped interlocks at the meeting rail and double layered weather-stripping on the sashes maximize resistance to air, water and dust infiltration.
  • Three additional custom hardware colors available: Brass, Oil-Rubbed Bronze and Antique Brass.
  • Oak laminate windows come standard with Sandlewood hardware.
  • Also available in a wide variety of standard sizes in our Classic Series.
  • Installation Instructions
  • Visit our Dealer Locator or call 1-877-565-0159 for a dealer nearest you.
  • Standard Glass

    Our Standard LoĒ²™ 272/Argon Glass Is Anything But Standard

    loe3_seasons_graphicThermo-Tech Classic Series Windows come standard with double-pane insulated LoĒ²™ 272/Argon glass featuring two panes of double-strength glass filled with argon gas for superior insulation. LoĒ²™ 272/Argon blocks enough solar heat that cooling loads can be cut by 25% or more compared to ordinary low-E and clear glass. The·heat of the sun is composed of visible light and invisible infrared energy. LoĒ²™ 272/Argon allows the daylight to pass through the glass and filters out solar heat, blocking 84% of the sun’s harmful ultraviolet rays. Plus the insulating value of LoĒ²™ is nearly double that of an ordinary non-LoĒ™ insulated glass.

    Available Glass Upgrades

    High-Performance LoĒ³™ 366/Argon

    Upgrade to LoĒ³™ 366/Argon heat-reflecting glass for even more insulating power and optimal thermal performance. LoĒ³™ 366/Argon heat-reflecting glass delivers the ideal balance of solar control, thermal performance, high visibility and the highest levels of energy saving in a double-pane insulated glass unit. Plus, LoĒ³™ 366/Argon provides excellent fade protection, blocking 11% more ultra violet light than standard LoĒ²™ 272 glass.

    • Lowers energy costs = saving on heating bill
    • Blocks 95% of harmful UV rays = reduced fading on carpet, furniture, etc
    • Year round comfort = cooler in summer, warmer in winter
    • Reduced condensation
    • Average heat loss reduction compared to standard double-pane glass is 50%

    Other Glass Options


    Obscure glass protects your privacy while allowing abundant light to enter the room. Choose from a variety of colors and texture patterns for a translucent to semi-opaque effect. Contact your dealer for more information. Visit our Dealer Locator or call 1-877-565-0159 for a dealer nearest you.

    Grey or Bronze Tinted

    Tinted glass provides additional shading from direct sunlight and warm conditions. A variety of tones and thicknesses are available. Contact your dealer for more information. Visit our Dealer Locator or call 1-877-565-0159 for a dealer nearest you.

    Tempered Safety Glass

    Tempered safety glass is extremely strong and often used for its safety characteristics. If tempered saftey glass does break, it breaks into small pieces without sharp edges. Standard for patio door, side lights and even bathroom shower and tub enclosures, tempered safety glass is ideal for reducing the likelihood of injury in the event of breakage. Contact your dealer for more information. Visit our Dealer Locator or call 1-877-565-0159 for a dealer nearest you.

  • Color Options

    Exterior Frame Colors

    In addition to standard white vinyl, frames are available in two other exterior colors to match virtually any home style or color.








    Interior Wood Laminate Colors

    Get the warmth and classic beauty of wood with the comfort and ease-of-maintenance of vinyl. At Thermo-Tech, we never stop improving our vinyl windows and doors. We always start with expert design, durable construction and maintenance-free 100% virgin vinyl. But it’s the finishing touches that are turning heads – like our wood laminates featuring the warmth of wood and the maintenance-free insulating power of vinyl.


    Light Oak


    Dark Oak

    Available on our 2-lite Classic Patio Doors, Fixed Casements, Direct-Set Picture Windows, Double-Hungs, Sliders, Casements, and our Geometric and Radius Windows. Available in White or Sandlewood exterior.

  • Custom Hardware Colors

    Heavy-duty low-profile hardware is available in white, tan or sandlewood to match your window color. Or choose optional metallic finishes for a more elegant look.

    Standard Hardware Colors







    Custom Hardware Colors




    Antique Brass


    Rubbed Oil Bronze

  • replacement_frame_system

    Custom-Sized Replacement Frame Systems

    More options for a truly custom fit!

    Thermo-Fit custom replacement windows and doors are designed to install easily without disturbing paint, siding or stucco.

    1. Custom fit brick mould with nailing flange
    2. Custom fit replacement brick mould
    3. Custom fit with nailing flange
    4. Custom fit replacement insert

    Trimline Brick Mould

    trimline cutaway

    Easily add a custom look with our new Trimline brick mould featuring a more traditional contoured face.


    • Now available in shapes!
    • Trim face easily snaps on to hide fasteners
    • Available in 1-1/2 or 2-inch
    • Multi-chambers and welded corners to match the strength of our windows
    • Sill nose available
    • White, tan or sandlewood colors plus two interior wood grain laminates
    • Available in Classic Series and Thermo-Fit
  • Distinctive Grid Styles


    Flat grids between the glass are available in a variety of configurations and colors to match our vinyl windows and doors.

    Flat Grids Configurations


    Grid configurations vary by window style and size. Please ask your dealer for more information about grid options for specific window styles and sizes.

  • Energy and Structural Performance Data

    Thermo-Tech Premium Windows and Doors are thoroughly tested for structural and thermal performance according to the most widely recognized national standards, including the American Architectural Manufacturers Association (AAMA) window specifications. The numbers tell the story: every Thermo-Tech product is built for a lifetime of reliable, energy-saving performance.

    When you're shopping, compare structural and thermal performance ratings. Look for the performance grade (PG), which measures the window’s resistance to wind and rain. The higher the PG rating, the better. And check out the National Fenestration Rating Council (NFRC) label for an accurate method to evaluate a product’s energy performance and to ensure the windows are Energy Star® compliant in your area. Thermo-Tech windows are Energy Star® rated in both the U.S. and Canada.

    See how Thermo-Tech Premium Windows and Doors measure up. Check out the performance data >

Thermo-Fit Window Styles

Select a window style from below to learn more.

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warm edge technology

Warm Edge Technology

Reduces interior condensation and cloudy glass.

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insulated glass

Insulated Glass

At the heart of every Thermo-Tech window and door.

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photo gallery

Inspirations Photo Gallery

Some of the most photogenic windows and doors around.

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