Get what you pay for! Windows are an important investment at K & J Windows. They can reduce energy costs, add to your home’s curb appeal, improve ventilation, reduce condensation and make your home more comfortable to live in. That’s why it pays to invest a little time in learning about the most important window features.


Each frame material has advantages. It’s time to pick the best one for you.  Choosing the right frame material is an important place to start. But each frame material has pluses and minuses and will excel in different applications. What’s more, each material offers varying degrees of quality, depending on the manufacturer. That’s why it pays to choose the right material for the right application—and always buy quality. After all, you want your windows and doors to last and perform well for years.

A vinyl window can be inexpensive, durable and remarkably energy efficient when designed properly to minimize thermal transfer. While early vinyl windows had problems with thermal expansion (the vinyl sash would expand or contract at a different rate from the glass and cause leaks) and stability in very hot environments, modern vinyl windows are much more durable and dimensionally stable. Look for vinyl window frames with heat-welded joints — they’re stiffer than mechanically joined vinyl frames and thus provide better resistance to temperature stresses. Interior webs also strengthen the frame and improve its thermal performance.

Vinyl windows are made primarily from polyvinyl chloride (PVC). This material has many advantages, including being virtually maintenance-free. It can’t be painted, but is often available in white and various neutral colors that complement many house colors. Because the color goes all the way through the material, scratches and dings are nearly impossible to see. Consequently, a vinyl window or patio door can look nearly new for years.

There will be differences in the quality of one manufacturer’s vinyl compared to another. This is because a vinyl window frame is made from a compound—a recipe of sorts—that dictates its performance over time. Each additive to a company’s vinyl recipe helps determine the long-term characteristics of the final product, like its weather and impact resistance. For example, Titanium Dioxide makes the vinyl more heat resistant. At first glance, competing windows may look the same, but there can be key differences in the vinyl recipe used and how vinyl parts are formed to make a window structurally strong and optimize insulation performance.

Vinyl Window and Door Frame Benefits

  • Exceptionally energy efficient
  • Extremely durable
  • Non-corroding
  • Virtually maintenance-free
  • Available in a wide range of styles and shapes
  • Cost effective
  • Easy to install

Fiberglass is a frame material known for it’s strength, durability and performance. As a building material, fiberglass is nothing new. It’s been floating boats and adding strength to ladders for years. But, until recently, the complex profiles required for window designs have been impossible to attain with fiberglass. Innovative window manufacturers like Milgard® have solved these challenges and today you can buy fiberglass windows and patio doors designed to maintain their beauty in every season, in any climate.

Fiber Glass Window Component Phoenix ArizonaFiberglass is impervious to water, cold, heat, insects, salt air and ultraviolet rays—all the traditional enemies of windows and doors. Unlike wood, fiberglass frames won’t crack from dryness, swell, peel or warp. What’s more, because fiberglass frames are essentially glass fibers and resin, the frames expand and contract very little and at approximately the same rate as glass. This puts less stress on the seals and increases their life and effectiveness.

Fiberglass also is popular because, just like a wood window frame, you can paint it. But there is one important difference—you don’t need to treat a fiberglass frame with toxic preservatives to prevent rot and decay, and it won’t deteriorate if the paint gets scraped off or otherwise damaged.

Fiberglass frames also are popular because a wood veneer can be added to the interior. This gives you the best of both worlds: the durability of a fiberglass frame exterior and the warmth and beauty of a wood interior.

Generally more expensive than windows and doors made out of vinyl or aluminum, fiberglass windows and patio doors can be a better value over time. Their attractiveness adds greater value to your home than these other window materials. Equally important, their durability and long life enable them to hold their value for years.

Fiberglass Window and Door Frame Benefits:

  • Ultimate in durability
  • Energy efficient
  • Extremely strong—can hold large expanses of glass
  • Virtually maintenance-free
  • Expand and contract very little with temperature changes
  • Won’t decay
  • Conducts minimal heat and cold
  • Available in a variety of factory-painted colors
  • Paintable

Architects and builders have long appreciated aluminum frame windows and replacement aluminum windows for their overall strength, lasting value and configurability to maximize views. Milgard takes aluminum windows a step further than most manufacturers by treating them not as just a low-cost alternative, but as an architectural design element. As a result, our unique aluminum windows are found in projects ranging from entry-level homes and multifamily projects to high-end custom homes and light commercial applications.

All our aluminum windows are custom made to your home’s exact specifications at no extra charge or extended lead time. Plus they’re covered by our industry-leading Full Lifetime Warranty.

For years, wood has been readily available window substrate, and the most common choice for homes. It’s advantages were it could either be painted a solid color or stained and sealed to show off the wood grain. Wood also is strong and easy to work with, is a natural insulator and complements many forms of traditional home architecture.There are some significant downsides to a wood window, however, that have driven many builders and homeowners to switch to other frame materials. Wood frame exteriors require a lot of regular maintenance. Whether you seal, stain or paint them, regular maintenance to the exterior with frequent touch-ups and occasional refurbishing, sanding and applying new coats is almost always required. Wood windows also are prone to rot, which can damage their integrity and make it difficult for them to hold paint. Nonetheless, a properly maintained wood window can last for years.

Some manufacturers of wood windows will offer cladding as an alternative to vinyl and fiberglass. However, some clad materials can conduct heat and cold while others offer limited color options and cannot be painted. And the wood beneath almost all cladding is susceptible to water damage that seeps behind the clad material and rots the wood.

Wood Window and Door Frame Benefits

  • Visually appealing, especially with a clear stain or finish emphasizing the natural wood appearance
  • Custom colors and designs
  • Provides excellent insulation
  • Traditional look fits many home styles

Composite windows can mean a variety of different things to different manufacturers, but generally come in two basic types—fiberglass and a wood/plastic composite. The newer type of composite window that is becoming available uses chemically–bonded blends of wood and plastic resins, and there are even versions made from a blend of wood chips and recycled plastic. However, with the exception of fiberglass, most composite frames are fairly new to the market, and as a result, there is no conclusive evidence to determine how these materials hold up over time.


Glass is more than just about energy efficiency. The best window manufacturers offer many combinations of window glass for everything from sun and noise protection to ensuring your privacy and safety.

Read all about your glass options here >


Know your hardware. Look for durability and security. One way to spot a quality window or patio door is by its hardware. It shouldn’t be flimsy. It shouldn’t feel cheap. And whether it’s a door handle or an operating handle for a window crank or lock, it should work smoothly and securely. In the case of the lock, it should close with a definite click and movement that lets you know both by feel and appearance that the window is locked and secure.

Some of the best window and door hardware is made from stainless steel. Why stainless? It’s strong, it can withstand years of use, it won’t corrode or pit, and it accepts a variety of finishes ( such as paint, polished brass or brushed chrome).

smarttouch-lockOne way to validate quality is to ask a dealer or contractor if a window or door lock mechanism meets or exceeds your area’s forced entry codes. You want hardware that will provide safety and security for your family year-round. French patio doors should have reinforced lock/latch regions for additional strength and security.

Ease-of-use features are extremely important for all of us. Whether we have kids, hard to reach windows or arthritis and other joint ailments that affect the hands and fingers, operating locks or latches can be difficult. Simple operation should be a consideration in choosing hardware like door knobs and locks.

hardware-3When selecting horizontal sliding windows and sliding patio doors, it’s important to test how smoothly their rollers move in their tracks and how much effort it takes. The window or door should feel snug in its tracks, but move easily. It should feel more like it’s floating than sliding. Heavy-duty nylon rollers will allow even large windows to glide effortlessly. Sliding door panels will move most easily when mounted on a raised monorail track. Independent-action, stainless-steel rollers will ensure smooth, effortless opening and closing.

In selecting in-swing or out-swing patio doors, look for hinges that are heavy-duty and preferably adjustable to allow for vertical and horizontal panel adjustments.

Finally, and equally important, there is the aesthetics of window and door hardware. It should be attractive in form and design, and be available in colors that complement the window or door itself, as well as home interior colors. For casement and awning windows, features like crank handles that fold down provide a more streamlined look and help avoid interference with blinds.


Get creative. Doors and windows as works of art. Imagine the morning sunlight gently entering a room. As the light warms your room, you notice a delightful mosaic of light and shadows reflecting on the wall—a reflection of the grid design you’ve chosen for your windows or patio door.

Door and window grids are a distinctive way to liven up the look of your home, whether you’re admiring it from the inside or out. Grids can make a window or door match a historical period or architectural style. They can also turn a large open pane into something extraordinary.

The types of door and window grids available to you will depend on the manufacturer and the material of the door or window (i.e., vinyl, aluminum, fiberglass). You can classify grids based on where they’re placed on the pane (between the two panes of insulated glass, on the exterior glass or on the interior glass). Door and window grids positioned between the panes make the window easiest to clean, though interior and exterior grids usually are designed as “snap-in grids” that can be removed and reattached easily and quickly. The profile of a grid can sometimes be shaped flat while other times it is sculptured.

Originally, grids were used as a way to both create visual interest in a window or door and to hold the various individual panes (lites) that made up that window or door. With insulated glass, it’s not only more cost-effective, to simulate a divided pane, it’s also easier to clean.

True Divided Lites

Individual panes of glass are held together with built-in muntin grids to accurately recreate the look of colonial-era homes.

Simulated Divided Lites (Option A)

To create a realistic look of divided lites from the interior perspective only, you can use a grid on the interior side of the window in combination with a grid between the panes.

Simulated Divided Lites (Option B)

To create a realistic effect of divided lites from the exterior perspective only, you can use a grid on the exterior side of the window in combination with a grid between the panes.

Grids Between the Glass

You also can just rely on a grid between the panes to simulate the look of lites. From a close-up perspective, you lose the dimensional effect and look of a physical grid on the outside of the pane, but retain the overall look of divided lites.

Finally, and equally important, there is the aesthetics of window and door hardware. It should be attractive in form and design, and be available in colors that complement the window or door itself, as well as home interior colors. For casement and awning windows, features like crank handles that fold down provide a more streamlined look and help avoid interference with blinds.


Let nothing in but the breeze. And the view.Window screens are primarily designed to let in fresh air and keep most everything else out. The most common materials used for screens are aluminum and fiberglass.

  • Aluminum screens generally come natural or with an applied charcoal color. Charcoal is much less visible and preferable where views are important.
  • Fiberglass screens are available in light gray as well as charcoal. Charcoal offers better views and superior appearance. Fiberglass screens have the advantage over aluminum of not denting like aluminum when hit or pushed. Made from extremely fine fibers of glass, fiberglass won’t corrode and is very strong and durable. For these reasons, fiberglass window screens today far outsell aluminum screens.

Screen Positioning

With most windows or doors, screens are placed on the exterior side so that you can open and close the window from the inside of your home. The exception is for casement and awning windows. These have the screens on the interior side of the window so that the window can be cranked open for ventilation. An advantage of this positioning is that the screens generally stay cleaner longer than exterior screens.

Retractable Screens

Several manufacturers offer sliding door screens that roll into a pocket when not in use. These screens virtually disappear when you don’t need them. They usually have a built-in dampening system for smooth, easy retraction—they won’t slam shut if accidentally released. They stay cleaner longer because the screen is protected from dirt, dust and weather when not in use. And there are other advantages—the screen expands when struck by a ball or other object.