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Marvin Next Generation Ultimate Double Hung Round Top

The Next Generation Ultimate Double Hung Round Top will add traditional arching and elegant lines to your home or historic preservation project. These versatile windows can range from a large dramatic focal point to a subtle accent to a roof line to enhance your home design.

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Features & Options
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  • Multi-point Locking System: Revolutionary system locks directly into the jamb
  • Aluminum Inter-lock: Eliminates drafts and improves the overall structural performance
  • Vent Mode: Allows you to lock the window while it is open 4 inches.
  • Narrow Checkrail: A 1 15/16” checkrail provides a traditional look.
  • Complete Wood Interior
  • Shorter Sill Liner
  • 14 degree sill bevel

How It Works

  • Auto-locking System: The first system of its kind. The window automatically locks when the window is closed. An audible “click” tells you it is locked.
  • Independent Sash Operation: Each sash can be locked while the other is open.
  • Ease of Operation: Improved balance systems make the sash operate smoothly at all sizes
  • Easy Tilt: Sashes can tilt in for easy cleaning.

Round Tops

RT6 Operating Double Hung - A classic look with a gentle eyebrow radius. Beautiful as a standalone window or as part of an assembly. Available in 192 call number sizes.

RT2 Transom - This simulated half circle transom window can be sized to stand alone or easily fit above a Double Hung window. Available in 12 call number sizes.

RT6 Transom and Picture - This stationary window is available as a transom or picture window. These windows are designed to complement the Next Generation Ultimate Double Hung window with complementary sizes and matching at springline. The transom is available in 20 call number sizes and the Picture is available in 55 call number sizes

RT2 Operating Double Hung - A dramatic window with a true half circle arch. The look gives a beautifully smooth transition from jamb to header. Both of the sash are operable. Available in 164 call number sizes.

RT21/22 Operating Single Hung - This striking window style adds elegant curve to a two wide window assembly. Available 189 call number sizes per shape.

RT6 Operating Double Hung

RT6 Operating Double Hung

RT2 Transom

RT2 Transom

RT6 Transom and Picture

RT6 Transom and Picture

RT2 Operating Double Hung

RT2 Operating Double Hung

RT21/22 Operating Single Hung

RT21/22 Operating Single Hung

Standard Specifications

  • One-lite Low E2 with argon insulating glass
  • Bare wood interior
  • Satin Taupe keeperless lock
  • Auto Lock – sash locking system
  • Independent locking sash
  • Vent Mode
  • Tiltable sash for easy washing
  • 14 degree sill bevel
  • DP 50 performance rating on most sizes

Professional Resources
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Energy Information Finder

This tool provides some of the most common options on windows and doors and related NFRC values. For more information about the energy efficiency of specific products and options, please contact your local Marvin sales representative.

See Energy Efficient Windows and Doors for further information on this topic.

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