4000 Series
6000 Series

4000 Series Double-Hung

double hung 4000 seriesFeaturing a beautifully refined silhouette and advanced energy-saving technology, our 4000 Series delivers exceptional style, strength, energy efficiency and value – everything today’s homeowners are looking for in a quality replacement window, and more.

This next-generation 4000 Series is precision-engineered to meet or exceed stringent ENERGY STAR® requirements, providing triple-pane energy-saving performance in a dual-pane unit. The dual-pane, double-strength insulated glass, thermally optimized frame and sash and non-conductive composite reinforcements are just part of the advanced energy engineering that puts 4000 Series Windows in a class all their own – premium window performance with everyday affordability. With Window World Windows your home will have a fresh, energy-efficient, low-maintenance solution back by an all-inclusive lifetime limited warranty.

Best-in-Class Performance Features:

  • double hung 4000 seriesReinforced narrow silhouette frame and sash profiles make a statement of style with their low-profile design. The result is a beautiful and expanded glass area. At the same time, internal chambers increase structural integrity, rigidity and energy efficiency.
  • Composite meeting-rail reinforcement allows for secure mounting of hardware; the non-conductive material helps reduce the transfer of energy.
  • End-of-throw cam shift locking delivers increased strength and protection to the recessed lock. It also includes an “unlocked” indicator.
  • The smooth and uniform, true sloped sill quickly directs water runoff without the use of weep holes, keeping the exterior of the window clean and attractive.
  • Our telescoping sill dam delivers a triple payoff; protection from air and water infiltration, increased structural stability and enhanced beauty.
  • When extreme wind and weather hit, our proprietary sill interlock stands strong. Traditional slope sill designs can allow the sash to bow during powerful winds, but with our interlocking sash-to-sill technology, the sash is channeled firmly into the window frame for a unified wall of strength.
  • Our innovative screen bulb seal creates a snug fit that eliminates light and insect penetration between the screen and frame. It also aids in easy screen installation and removal.

double hung 4000 seriesopening your double hung 4000 series

cleaning your double hung 4000 series
Both sashes of Window World Double-Hung Windows tilt in for easier, safer cleaning from inside your home.

Additional Sliding Window Features:

  • Sashes glide horizontally for easy opening and closing.
  • Both sashes lift out for convenient cleaning.
  • Nylon-encased dual brass roller system for smooth gliding performance.

Insulated Glass Packages to Meet Your Needs

Maximize your energy savings by choosing a high performance SolarZone insulated glass package to meet your specific climate challenges. The lower the U-Value, the less energy you’ll need to heat your home. The lower the Solar Heat Gain Coefficient (SHGC), the more you’ll conserve on air conditioning.

Thermal Performance Comparison
*Whole window values are based on double-strength glass, standard 4000 Series offering with composite reinforcements. ST and HP performance values are also available.
Double-Hung Sliding
U-Factor SHGC U-Factor SHGC
Clear Glass 0.46 0.59 0.45 0.57
SolarZone 0.29 0.30 0.28 0.30
SolarZone Elite 0.28 0.21 0.28 0.20
SolarZone iE 0.28 0.30 0.28 0.30
SolarZone ThermD 0.28 0.30 0.27 0.30
SolarZone ThermD Elite 0.27 0.21 0.27 0.20
SolarZone ThermD iE 0.27 0.30 0.26 0.30

Clear: Double-paned clear glass unit.
SolarZone: Double-paned unit with one pane of Low-E glass, argon gas and metal alloy Intercept spacer.
SolarZone Elite: Double-paned unit with one pane of Low-E SHGC glass, argon gas and metal alloy Intercept spacer.
SolarZone iE: Double-paned unit with one pane of Low-E glass, argon gas and metal alloy Intercept spacer, along with insulation-enhanced mainframe.
SolarZone ThermD: Double-paned unit with one pane of Low-E glass, argon gas and stainless steel Intercept spacer.
SolarZone ThermD Elite: Double-paned unit with one page of Low-E SHGC glass, argon gas and stainless steel Intercept spacer.
SolarZone ThermD iE: Double-paned unit with one pane of Low-E glass, argon gas and stainless steel Intercept spacer, along with insulation-enhanced mainframe.

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6000 Series Double Hung

img-6000-series-double-hungWindow World 6000 replacement windows offer superior style and quality. Our 6000 Series windows offer our SolarZone TG2 Elite™ package as a standard, making it the most energy efficient window available. A closer look reveals this crafted style is made even stronger through advanced engineering details. Solid vinyl construction and operating hardware that’s been time-tested for decades makes the 6000 series window the ideal pick if you’re looking for design flexibility.

Window World 6000 Series windows are available in double-hung, slider, casement, awning, picture window and architectural shapes configurations.

Take a closer look at the 6000 Series R-5 windows


Color Options


img-solarzone-energyGlass Options

SolarZone TG2 Elite™ insulated glass packages are standard on our 6000 Series windows to help you save heating and cooling costs while keeping your home more comfortable. In warm weather, SolarZone reduces solar heat gain, minimizing interior glare and lowers interior glass temperature, saving energy and making your home more comfortable. In cool weather, SolarZone provides outstanding thermal performance with warmer interior glass surfaces to help save energy and maintain comfort during a cold winter.

Meets ENERGY STAR® requirements in all Zones.

Additional Features


Grid Options

Flat and simulated divided lite grids are available in standard and custom patterns.

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