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Window grids: Styles, patterns and how to choose the right look

Aug 29, 2023|Updated Oct 12, 2026

Window grids are decorative patterns that divide the glass visually and add architectural character to your windows. Common styles include colonial, prairie and custom designs that complement different home aesthetics. Choosing the right grid pattern depends on your home’s architecture, the amount of visual detail you prefer and the overall look you want to achieve.

Window grids, or window grilles, often appear in homes to add architectural interest. They can also maintain the continuity of a home’s style. A lot of terms get used to describe window grids. Here’s a handy window grids guide to help you make the best choice for your home.

The exterior of a colonial home with Infinity from Marvin double hung windows.

Window grid terminology

When it comes to window grids there are several terms to describe them. The terms are often used interchangeably. Window grids are also known as grilles, dividers, muntins, or mullions.

In the past, mullions used to support window glass pieces in single-pane windows. Now they serve decorative purposes.

Muntins also refer to the bars or dividers that form the decorative grille pattern of a window or door. Grilles specifically refer to muntins fastened to the interior side of a window sash.

Grids in windows are also called grilles. Muntins, also known as dividers or bars, create the grids and grilles.

If you're interested in learning more, request a free in-home appointment with an Infinity design consultant.

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Common window grid terms

There are many terms and synonyms with different types of window grids. It’s a good idea to familiarize yourself with the various terms before you get started on a window or door replacement project.

Mullion

A vertical bar of a sash that divides the sash into different sections. In older windows they supported window glass pieces, but now serve decorative functions.

Muntins

Bars that form the decorative grille pattern on a window or door. Also known as dividers.

Grilles

Muntins fastened to the interior of the sash to create the effect of divided lites.

Grilles Between the Glass (GBGs)

Dividers placed between the panes of insulated glass to simulate authentic divided lites. GBGs allow for easier window cleaning with no bars on the exterior or interior surface of the glass.

Simulated Divided Lites (SDLs)

Simulated Divided Lites have bars permanently attached to the outside surface of glass to form grids. The grids mimic traditional looks and can form symmetrical looks. SDLs can increase the appeal of a house by adding visual interest.

Infinity window grille types

Infinity offers two types of window grilles: Simulated Divided Lites and Grilles Between the Glass. There are many types of custom patterns you can build with those grilles. The difference between Simulated Divided Lites and Grilles Between the Glass is the location of the bars.

Divided Lites on an Infinity from Marvin door.

Simulated Divided Lites (SDLs)

Simulated Divided Lites have bars permanently attached to the outside surface of the glass to form grids. The grids mimic traditional looks and can form symmetrical patterns. SDLs can increase the appeal of a house by adding visual interest.

Grilles Between the Glass (GBGs)

Grilles Between the Glass can also create grids. They differ from Simulated Divided Lites because the bars sit between the panes of glass. GBGs offer easier window cleaning because you don't have to work around the muntins, like with Simulated Divided Lites.

Window grille patterns

Rectangular

Prairie style homes feature window grids that divide the window into unequal sizes. The grille runs near the perimeter of the window and creates architectural appeal.

Prairie style grids can have four, six, or nine unequal rectangles or panes. The lines of Prairie style grids create a sense of a prairie landscape. Craftsman and Farmhouse style homes often feature Prairie grille styles.

A simulated check rail appears on casement windows to look like a double-hung or single-hung window.

Divided Lite patterns displayed on an Infinity from Marvin window.

Traditional

Prairie Four-Lite

Prairie Six-Lite

Prairie Nine-Lite

Cottage One-High

Simulated Check Rail

Round

Round grille patterns feature spokes and hubs to make them unique. Our circle window can have six spokes while our round top windows can have three. Hubs can appear open or solid.

Circle Dual Hub Six Spokes

Half Round Above Springline Dual Hub Three Spokes

Half Round Above Springline Open Hub Three Spokes

Half Round Solid Hub Three Spokes

Equal Rectangle

Quarter Round Open Hub

Home styles that use grille patterns

Grille patterns are often used to preserve the historic aspects of a home’s style. They can also maintain a consistent look. Many of the grille styles include Prairie in the name as in Prairie style homes.

Exterior view of a bungalow home featuring Infinity windows.

Prairie style homes and prairie window grids

Prairie style homes feature window grids that divide the window into unequal sizes. The grille runs near the perimeter of the window and creates architectural appeal.

White brick home exterior with brown Infinity casement and picture windows.

Traditional home styles and traditional window grids

A traditional home style places an emphasis on window symmetry. When window grilles appear, they’ll take on the traditional style of window grids to maintain a balanced look. Georgian homes also feature symmetrical window grilles. Traditional window grids divide the window into equal sections. The pattern can appear on both sashes of a single-hung or a double-hung window. You can also choose to just have the pattern on the upper sash.

Exterior view of a two-panel Inswing French door with Prairie lites.

Craftsman home style

Craftsman homes with window grilles differ from other grille patterns. Often only the top half of the window will have grilles. The pattern leaves ample viewing area while incorporating some design elements.

A white kitchen with an Infinity by Marvin casement window by the sink.

Farmhouse style home

Farmhouse style homes can feature traditional window grille styles for symmetrical looks. Often the grid style separates the glass into four equal rectangles.

How to choose the right window grilles

Consider these factors when choosing between SDLs and GBGs:

Window grille maintenance

GBGs require virtually no maintenance since they're sealed between glass panes. SDLs necessitate careful cleaning around the adhered bars, which can trap dust between routine window cleanings.

Aesthetic appearance

SDLs create a more three-dimensional, authentic appearance with shadows and depth, often attributed to more classical home styles. GBGs offer a cleaner, more contemporary look with flush glass surfaces.

Window grille cost differences

Generally, SDLs represent a premium option with higher costs due to their more intricate construction. GBGs tend to cost less while still providing a decorative window grilles pattern.

The hidden value — authenticity and character

Window grilles offer benefits that enhance your home's overall appeal:

Historical accuracy: For period homes, the right window grilles can maintain architectural integrity and historical authenticity.
Enhanced curb appeal: Well-designed window grilles can boost your home's appearance and potential resale value.
Reflect your style: Your choice of window grilles allows you to express your personal style while complementing your home's architecture.

While window grilles may seem like a small detail, their impact on your home's appearance, maintenance requirements, and character make them an important consideration when buying new windows.

See how Infinity transforms your home

Use our design tool to visualize your new replacement windows with grilles. Upload images of your home to get the look you want or start with a sample home and determine the best window grilles pattern for you.

Frequently asked questions

Why do people put grids in windows?

Grids used to hold individual panes of glass in place in single-pane windows. They became a characteristic look for that home style. Today, grids serve decorative purposes to add appeal to your home.

Are window grids outdated?

Window grilles aren’t outdated. They appear in many home styles and have found new popularity with Farmhouse style homes.

How to replace window grids?

Infinity Simulated Divided Lites get permanently adhered to the outside surface of the glass. Our Grilles Between the Glass window grids rest between window panes. If you’re interested in replacing window grids, it’s best to schedule a service appointment with your local Infinity consultant.

What are window grilles?

Window grilles are decorative bars that get attached to a window. The bars divide the window into separate sections. Window grilles complement home styles.

What are grids in windows called?

Grids in windows are also called grilles, dividers, muntins, or mullions. They refer to the bars on windows that divide the window into different spaces. Some window grids separate a window in equal proportions. Others create different shaped rectangles near the perimeter of the window.

Can you remove window grids between glass?

If you want to remove window grids between glass, it’s best for a professional to do so. Removing window grids between glass on double-pane windows poses challenges that only professionals can handle. Trying to remove window grids between glass can lead to damaging your windows and compromising their energy efficiency if you break the seal between the glass.

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