What are the Best Window Coverings to Keep Heat Out?

Looking for more ways to keep the heat out?

Sun-filled rooms are beautiful. Rooms that feel ten degrees warmer by mid-afternoon? Less so.

Windows can let a surprising amount of solar heat into your home, particularly when they’re large, unshaded or facing the strongest part of the day’s sun. The right window coverings can help reduce that heat, soften glare, protect furnishings from UV exposure and make your rooms more comfortable without shutting out daylight completely.

From insulating cellular shades to adjustable shutters and view-preserving solar shades, this guide explores the best window blinds to keep heat out and explains how to choose the right option for your space.

At a Glance

Cellular shades are usually the best window blinds to keep heat out because their honeycomb pockets help insulate the window. Window shutters are another strong choice, creating a substantial barrier while giving you adjustable control over sunlight, privacy and heat. Solar shades help reduce glare and UV exposure while preserving more of the view, and blackout shades work well in bedrooms and media rooms.

Whichever style you choose, a close custom fit matters. For better heat control, close your window coverings before direct sunlight reaches the glass rather than waiting until the room already feels warm.

How Window Coverings Help Keep Heat Out

Solar heat gain happens when sunlight passes through a window and warms the surfaces inside your home. Floors, walls and furniture absorb that energy, then release it into the room as heat. According to the U.S. Department of Energy, about 76% of the sunlight that reaches a standard double-pane window enters the home as heat during cooling seasons.

Window treatments for heat reduction help in several ways:

• Insulating: Cellular pockets, solid panels and layered fabrics slow heat transfer between the glass and the room.
• Blocking: Opaque materials prevent direct sunlight from reaching floors and furnishings.
• Reflecting: Light-colored or reflective surfaces send more solar energy back toward the window.
• Filtering: Solar fabrics reduce glare and UV rays while allowing some daylight and visibility.
• Reducing air movement: Close-fitting window coverings hold a layer of air near the glass, creating an additional buffer.

That means the best window coverings for heat control aren’t always the thickest or darkest. Construction, material, color, fit and the time of day you close them all affect their performance.

Which Window Coverings Are Best for Heat Reduction?

1. Cellular Shades for Strong Insulation

Cellular shades, also known as honeycomb shades, are among the most effective heat-reducing window blinds. Their pleated cells hold pockets of air, helping slow the movement of heat through the window.

The Department of Energy notes that tightly installed cellular shades can reduce unwanted solar heat through windows by up to 60% during cooling seasons. Their insulating construction can also help reduce heat loss when temperatures fall, making them useful throughout the year.

For better thermal performance, look for double-cell construction, a close fit and minimal gaps around the edges. Blackout cellular fabrics can provide additional light control in bedrooms, nurseries and media rooms, while light-filtering options keep the space feeling brighter.

An inside mount creates a streamlined look. An outside mount can cover more of the window frame and may reduce light gaps, particularly when the recess is shallow or uneven.

Our No-Drill Cordless Complete Blackout Cellular Shades combine insulating honeycomb cells with blackout fabric and a drill-free installation. Cordless Blackout Cellular Shades have also been featured in our guide to NYT Wirecutter’s blackout shade pick.

2. Solar Shades for Heat, Glare and UV Control

Solar shades use performance fabrics to filter sunlight before it fills the room with glare and heat. They’re especially useful in home offices, living rooms and spaces with large windows or a view you don’t want to hide.

The key detail is the openness factor, which describes how tightly the fabric is woven. A lower openness percentage provides more glare reduction, privacy and solar control, but limits more of the view. A higher percentage preserves more daylight and visibility while allowing more sunlight through.

For a west-facing room that heats up every afternoon, a tighter weave may offer the balance you need. In a shaded room where screen glare is the main problem, a more open fabric may be enough.

Color matters too. Light exterior-facing colors generally reflect more sunlight, while darker fabrics can improve outward visibility and glare control. Some products combine a decorative interior color with a lighter window-facing surface.

Solar fabrics are available in a range of openness levels, helping you find the right balance of natural light, view-through and heat reduction.

3. Shutters for Year-Round Insulation and Light Control

Interior shutters create a substantial barrier between the room and the glass. When their panels and louvers are closed, they help reduce direct sunlight, solar heat gain and air movement around the window.

Their biggest advantage is flexibility. You can tilt the louvers to block strong afternoon sun while still directing daylight into the room, or close them fully when heat control and privacy matter most. That makes shutters particularly useful for west-facing windows and rooms that become warmer later in the day.

Shutters can support comfort throughout the year by helping limit summer heat gain and reducing heat movement around the window during cooler weather. Their solid construction, long lifespan and easy-care finish also make them a practical choice for living rooms, bedrooms, kitchens and bathrooms.

A precise fit matters. Custom shutters that sit closely within or over the window opening provide better coverage than panels with large gaps. They also give you a durable way to manage daylight, privacy and temperature without changing the clean look of the window.

4. Blackout Roller Shades for Hot, Bright Rooms

Blackout roller shades are made with opaque materials that block nearly all light through the fabric. They’re a practical choice for bedrooms, nurseries, media rooms and other spaces where darkness matters as much as relief from direct sun.

Blackout fabric doesn’t automatically mean maximum insulation. Roller shades have a single layer of material and typically leave small gaps around their edges, so they don’t trap air in the same way as cellular shades. Still, blocking intense sunlight before it reaches the room can make a noticeable difference.

For better coverage, consider an outside mount that extends beyond the window opening. A light or reflective window-facing surface may also help send more sunlight back toward the glass.

If you’re comparing materials, look beyond color alone. Fabric density, edge coverage and the way the shade sits against the window can all affect how much direct light reaches the room.

5. Vertical Window Coverings for Large Windows and Doors

Sliding glass doors and wide windows bring in plenty of light. They can also bring in plenty of afternoon heat.

Vertical blinds and panel track shades make it easier to cover large areas of glass while preserving access to the door. Their vanes or panels can be adjusted as the sun moves across the room.

For more insulation, consider a vertical cellular design. Honeycomb pockets extend across the opening, bringing the insulating structure of cellular shades to sliding doors and extra-wide windows.

Choose Heat-Reducing Blinds for Your Window Direction

The direction your windows face affects when they receive sunlight and how strongly the room heats up.

• East-facing windows receive bright morning sun and may make bedrooms or breakfast areas warm early in the day.
• West-facing windows receive low, intense afternoon sunlight and are often among the hottest windows in the home.
• South-facing windows may receive sustained sunlight for much of the day, depending on the season and surrounding shade.
• North-facing windows usually receive softer, indirect light and may need less solar protection.

Window size matters too. A large wall of glass can create more solar heat gain than a small window facing the same direction. If you’re deciding where to upgrade first, start with large, unshaded east- and west-facing windows.

Fit and Color Make a Difference

When window blinds keep heat out effectively, the material is only part of the story. The way the covering fits the window matters too.

A close custom fit reduces the gaps where sunlight can enter. Depending on the window, an outside mount may provide more complete coverage than an inside mount. Side tracks, liners and layered window treatments can reduce gaps further when maximum light and heat control are priorities.

Color can also affect solar performance. Light-colored and reflective window-facing surfaces generally send more sunlight back toward the glass, while darker surfaces absorb more of it. However, construction and fit usually matter more than color alone.

A pale shade with large gaps may be less effective than a darker cellular shade fitted closely to the window. Focus on the complete setup rather than choosing by color alone.

Smart Shades Can Act Before the Room Heats Up

Timing is one of the easiest ways to improve heat control. Once sunlight has warmed the floor, furniture and walls, the room may stay hot even after you close the shade.

Motorized and automated window treatments can be scheduled to close before the strongest sunlight reaches the glass. This is particularly helpful for high windows, rooms that heat up while you’re away or spaces you don’t use throughout the day.

You might schedule east-facing shades to close in the morning and west-facing shades later in the afternoon. Once the direct sun has moved on, reopen them and let the daylight back in.

Layer Window Treatments for More Heat Control

Sometimes one window covering is enough. Sometimes the hottest room in the house needs backup.

Layering a fitted shade with curtains creates another air space between the glass and the room. It also gives you more ways to adjust privacy, daylight and style.

Useful combinations include:

• Cellular shades with lined drapes when insulation is the priority.
• Solar shades with curtains for daytime glare control and more privacy in the evening.
• Blackout roller shades with side panels to cover more of the light gaps around the window.
• Light-filtering shades with blackout drapery for soft daylight by day and greater coverage when needed.

Choose Window Treatments by Room

• Bedrooms: Try blackout cellular shades or blackout roller shades for a cooler, darker space to sleep.
• Living rooms: Light-filtering cellular shades, shutters or solar shades can reduce glare while keeping the room welcoming.
• Home offices: Solar shades help soften direct sunlight and make screens easier to see.
• Nurseries: Cordless blackout cellular or roller shades can support naps while helping reduce afternoon heat.
• Kitchens and bathrooms: Shutters and easy-care materials provide flexible light control and are simple to clean.
• Media rooms: Blackout shades reduce reflections and create a more comfortable viewing environment.
• Large windows and sliding glass doors: Vertical cellular shades, panel tracks and vertical blinds provide practical coverage without blocking access.

Frequently Asked Questions About Blinds and Heat

Do window blinds keep heat out?

Yes. Window blinds, shades and shutters can reduce solar heat gain by blocking, reflecting or filtering sunlight. Insulating products such as cellular shades also slow heat transfer through the window. Performance depends on the product, fit, window direction, climate and how consistently the covering is used.

Which blinds are best to keep out heat?

Cellular shades are one of the strongest choices for overall insulation because their honeycomb pockets trap air. Shutters provide a solid, adjustable barrier, while solar shades are useful for glare and UV control. For wide windows and sliding doors, vertical cellular shades offer insulating coverage across a larger area.

Are window shutters good for keeping heat out?

Yes. Shutters can help keep heat out by creating a substantial barrier over the window and reducing direct solar gain. Their adjustable louvers let you block strong sunlight without losing every bit of daylight. Cellular shades usually provide stronger insulation, but shutters combine heat control, privacy, durability and flexible light management.

Are blackout blinds good for heat reduction?

Blackout blinds and shades can help by stopping direct sunlight from entering the room. However, blackout describes light control rather than insulation. A blackout cellular shade generally provides more insulation than a single-layer blackout roller shade because of its air-pocket construction.

Are cellular shades or solar shades better for heat?

Cellular shades are generally better when insulation is the priority. Solar shades are often better when you want to reduce glare and UV exposure while preserving some of the view. The right choice depends on whether your main goal is thermal insulation, visibility, daylight control or a combination of all three.

Should blinds be open or closed to keep a room cool?

Close blinds or shades before direct sunlight reaches the window, particularly during the hottest part of the day. Open coverings on windows that aren’t receiving direct sunlight when you want more natural light. Adjusting them as the sun moves provides better heat control without leaving the whole home dark.

Is it better to keep blinds or curtains closed in hot weather?

Both can help, and they work especially well together. Cellular or solar shades paired with lined curtains create an additional layer between the room and the window. If you’re choosing one, cellular shades are a strong option for insulation, while solar shades reduce glare and preserve more of the view.

What window coverings are best for west-facing windows?

West-facing windows often receive strong afternoon sun, making them some of the hottest windows in the home. Cellular shades, shutters and solar shades are all effective choices. Motorized window treatments can also close automatically before the strongest sunlight reaches the glass.

Do light-colored blinds keep rooms cooler?

Light-colored and reflective window-facing surfaces can send more sunlight back toward the glass. However, color is only one factor. Construction, fabric density, edge gaps and the closeness of the fit can have a greater effect on overall performance.

Do custom-fit blinds make a difference?

Yes. A custom fit helps reduce gaps around the edges where sunlight can enter. Whether you choose cellular shades, shutters or roller shades, a close-fitting window covering will usually provide better heat and light control than one with large gaps.

Can blinds lower air-conditioning costs?

Energy-efficient window coverings can reduce unwanted heat gain and help rooms stay more comfortable, which may reduce the amount of cooling needed. Exact savings vary by climate, window type, home construction, product performance and how the window covering is operated.

Keep the Heat Out Without Shutting Out Your Style

The best window coverings for heat reduction make sunlight easier to live with. Cellular shades provide strong insulation, while window shutters create a solid, adjustable barrier that can help manage heat throughout the year. Solar shades soften glare while preserving more of the view, and blackout shades help darken hot, bright rooms.

Whichever style you choose, focus on three things: the right material, a close custom fit and good timing. Close your shades before the strongest sun arrives, then reopen them when the light feels welcome again.

Explore our energy-efficient and heat-reducing window coverings to find a cooler, more comfortable way to enjoy the light.