NorthWind® III Series


Top-tier EnergyStar rated windows by

National Vinyl

Why NorthWind® III Series?

National Vinyl's Northwind III Series fusion welded windows are virtually maintenance free, designed for smooth and effortless operation and will provide you with long lasting beauty for years to come. The Northwind Series III Replacement and remodeling product line is available only through authorized National Vinyl dealers and are typically installed by a contractor or remodeler.

The Northwind III Series windows are manufactured for longevity:

  • Fusion welded frame and sash - provide structural integrity and durability

  • Heavy-duty block and tackle balance system - provides years of easy sash operation

  • Multi-chambered hollows in frame and sash - create greater insulating and structural value

  • Fully interlocking meeting rail - protects against air filtration

  • Fully reinforced meeting rails - for structural integrity and lock longevity

The Northwind III Series windows are energy efficient and proven:

  • NFRC certified - meets the most stringed state code requirements

  • DuraLite™ 3/4" Dual insulated glass creates the best warm edge technology for year-round in-home comfort

  • ENERGY STAR® rated when ordered with Low-e glass and Argon Gas fill

  • Fully transferable Lifetime Limited Warranty

The Northwind III Series windows are designed for beauty and ease of use:

  • Slim profile - allows for maximum glass area letting more light in to your home

  • Beautiful soft bevel on sash - provides a more elegant and traditional look

  • Tilt in top and bottom sash - for safe, interior and exterior cleaning

  • Dual night latches - for night time ventilation

  • Integra style tilt latch - provide easy and ergonomic tilt feature with a beautiful clean look

  • One-piece lift rail top and bottom

  • Aluminum ½ screen with fiber glass screen mesh

  • Decorative beveled exterior - captures that classic look which complements every home

The Northwind III Series windows offer choices for customizing your look:

  • Available in eight standard colors in addition to white

  • Custom Colonial Style and Diamond Style grid options available

  • Grids can be between glass for effortless cleaning or SDL (Simulated Divided Lite) for a more true \"wood\" or traditional look

  • Decorative Grids available in a variety of colors and finishes

Fusion welded frame and sash - provide structural integrity and durability

Multi-chambered hollows in frame and sash - engineered to create vastly increased thermal insulating values to meet Energy Star's requirements. Bonus, it also increases the structural value of the window!

Fully weatherstripped sashes provide unequalled protection against air infiltration and increases thermal values.

One-piece lift rail top and bottom

Superior bulb seal where sash meets sill. This creates the best protection against air and water infiltration for greater peace of mind

True sloped sill design provides optimal water run-off eliminating water entry into home

Dual night latches - for night time ventilation

Decorative beveled exterior - captures that classic look which complements every home

Effortless Operation

Both top and bottom sashes are fully operational and easily tilt in for safe cleaning

Low Maintenance

National Vinyl windows never require painting, sanding or refinishing. Simple cleaning is the only maintenance required.

Energy Efficiency & Savings

If you are looking for an energy saving double hung, sliding,picture, hopper, casement and/or awning window, our NorthWind III Energy Advantage Series are a great choice. Our window products easily meet and can exceed the Energy Star requirements for thermal tests.

Energy Star Performance

As Energy Star Partners, all our window styles meet Energy Star. To reach Energy Star Ratings, the thermal efficiency is built right into the window: no foam, no krypton gas or triple glazing is necessary. Choose our Soft Coat Low E 3/4\" insulated dual pane glass with argon gas fill. Ccore®, for structural reinforcement and strength in addition to being thermally efficient. Rating results may vary by window style:

NorthWind Dual-Pane Double Hung Window

U-Value Solar Heat Gain (SHGC) Visual Transmittance (VT) Condensation Resistance (CR
0.27 0.28 0.52 62.0

NFRC Certified

Through continued technological advances in window design, we have engineered our windows to meet or exceed NFRC\'s stringent test standards without expensive upgrades. Our windows utilize the most advanced thermal insulated glass spacer and take advantage of the insulating properties of a multi-chambered sash and frame design. We utilize scientifically engineered PVC composite reinforcements for strength and durability.

Understanding NFRC Labels

R-5 Rated Performance

For windows with an R-5 rating, choose our Soft Coat Dual Low E 1\" insulated triple pane glass with argon gas fill and CCore® reinforcement for strength. Windows with an R-value (resistance) of 5 are among the most energy efficient windows on the market. In comparison, most ENERGY STAR rated windows generally obtain an R-value of 3. Increasing the R-value from 3 to 5, results in an average heat loss reduction of 30 percent to 40 percent.

NorthWind Triple-Pane Double Hung Window

U-Value Solar Heat Gain (SHGC) Visual Transmittance (VT) Condensation Resistance (CR)
0.20 0.21 0.34 73

Duralite® Warm-Edge Spacer

All of our vinyl windows are manufactured with Duralite® is a patented warm-edge spacer. Most window manufacturers use metal spacers to separate the panes in a double-glazed window. Spacers that contain metal conduct heat and cold through the spacer. National Vinyl uses Duralite, an insulating glass edge seal system constructed using a unique Composite Laminating Technology. Duralite creates a create a high-performance durable single seal spacer system.

Heat Loss Before Upgrade

Heat Loss After Upgrade

Customizable Shapes & Sizes

Limitless Color Options

Solid Vinyl

Our blend of uPVC is made of Virgin Vinyl and has color throughout. This is key for when you accidentally scratch the window it will still show its true color. Able to be cleaned with standard soap and water, it is easy to care for and will last a lifetime.

Painted Standard Offering

Our painting process is second to none. AAMA Certified and warranted for 15 years, our paint specialists are trained to be your expert in paint application. Our standard offering allows for you to match your windows to your homes décor. Available to be painted exterior only, interior only, or both.

Wood Grain Interior Staining

This truly one of a kind process pro-vides you with a low maintenance, authentic wood grain look and feel on a vinyl window. The look is unique and authentic. Like wood, no two pieces look alike, however you will be left with an authentic wood grain look and feel second to none and unlike any other vinyl window today.

Stained double hung, bronze hardware

Painted Custom Offering

When it comes to choices, we have you covered. Variety is the spice of life and we have it ready for you to Accessorize to your homes unique décor. You can pick from one of our already created custom colors or create one specially for you. Just give us a color swatch and we will do the rest.

Fully Transferable Lifetime Limited Warranty

Every one of our windows comes with one of the strongest warranties in the industry. With a lifetime limited warranty on vinyl, all movable parts as well as glass against seal failure, you can be confident with your National Vinyl LLC window purchase. In addition, our premium Destiny series also includes an additional glass breakage warranty.


All structural components (jambs, sashes, balances, casings, sills...) are covered for any defects.

Movable Parts

Coverage also includes tilting & sliding mechanisms, locks and all other mechanical components.


All windows are covered for glass against seal failure, the Destiny Series warranty also covers glass breakage.


Your lifetime warranty can be transferred to your home\'s new owner if you ever decide to sell your home.

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