Most people change their wardrobe when summer arrives. Their windows stay exactly the same. The heavy curtains that felt cozy in January are now trapping heat, blocking airflow, and making every sunny afternoon harder to deal with. Swapping to sheer curtains or lighter panels is a practical change with an immediate result.

Quick Take

• Take down: Velvet, fleece, thermal-lined, and heavily lined panels: anything thick or dark.
• Put up: Sheer curtains, cotton voile, linen blends, or light-filtering panels in white, ivory, or soft neutrals.
• Don't want two sets? Add a removable lining to your existing curtains, or layer a sheer panel closest to the window with a heavier panel on the outer rod.
• Timing: Keep south- and west-facing curtains closed midday; open east-facing ones in the afternoon.

Why Heavy Curtains Make Your Home Hotter in Summer

Windows account for 25 to 30 percent of residential cooling energy use, according to the U.S. Department of Energy. Much of that comes from what is hanging in front of them, not the glass itself.

Heavy curtains trap air between the fabric and the window. In winter that is the point. In summer, that trapped air heats up and radiates into the room. Three things make it worse:

• Dense, thick fabric holds heat in the window zone and slows airflow.
• Thermal or blackout lining is specifically engineered to block air movement. That is the opposite of what you need in July.
• Dark colors absorb solar radiation and convert it to heat instead of reflecting it away.

Replacing that weight and density with something lighter and airier is the fix.

The Fabrics Worth Putting Up for Summer (And the Ones to Box Away)

What to Put Up

• Sheer polyester or voile: Maximum light, good airflow, easy to wash.
• Cotton voile: Soft, breathable, moves well in a breeze.
• Linen blend: Natural texture, diffuses light without blocking it.
• Light-filtering panels (pale colors): Daytime privacy with minimal heat buildup.

What to Box Away

• Velvet: Dense and heavy, traps heat near the glass.
• Thermal-lined curtains: Blocks airflow by design.
• Blackout panels (dark colors): Absorbs solar heat, releases it into the room.
• Heavily interlined drapes: Weight and density hold warmth in the window zone.

White or pale blackout panels are the exception. They block light without absorbing heat, and can help keep a room cooler when kept closed during peak sun hours.

Does Curtain Color Affect Heat?

Yes, and the difference is larger than most people expect.

• White, ivory, cream: Reflects solar radiation: least heat gain.
• Soft grey, light beige: Reflects most radiation, a good summer choice.
• Medium tones (taupe, sage): Moderate heat absorption.
• Dark colors (navy, charcoal, forest green): Absorbs solar energy and releases it as heat indoors.

The U.S. Department of Energy notes that medium-colored draperies with white plastic backings can reduce solar heat gain by up to 33 percent. The lighter the curtain, the less heat it brings into the room. For any sun-facing window in summer, white or off-white is the most effective color choice.

Should You Keep Curtains Open or Closed in Summer?

The answer varies by window direction and time of day.

Window direction	Peak sun hours	Best approach
East-facing	Morning (6am–10am)	Close during morning sun, open by midday
South-facing	Midday (10am–2pm)	Keep closed during peak hours, open in evening
West-facing	Afternoon (2pm–6pm)	Most critical to keep closed: strongest afternoon heat
North-facing	Low direct sun all day	Can stay open; minimal heat gain

Close curtains on sun-facing windows before the room heats up, not after. Once heat is inside, curtains do little to remove it. The goal is to block solar gain at the glass.

At night, open everything. Letting cooler air in after sunset is the most effective passive cooling approach available. Sheer curtains make this easy without sacrificing privacy.

Room by Room: What to Swap and What to Keep

Living Room

Take down: Heavy lined drapes or velvet panels. Put up: Sheer curtains in white or natural tones. A double rod lets you layer a sheer with a light-filtering panel for flexible control throughout the day. Note: Highest priority: living rooms typically have the largest windows and most sun exposure.

Bedroom

Take down: Dark blackout curtains, especially on south- or west-facing windows. Put up: White or pale blackout panels, or a sheer-plus-blackout layered setup. Hang the sheer panel closest to the window and the blackout panel on the outer rod. You still need darkness for sleep. Light-colored blackout panels give you that without the heat absorption. Note: High priority for west-facing rooms.

Home Office

Take down: Any curtain causing afternoon glare or heat buildup near your desk. Put up: Light-filtering sheer curtains in a neutral tone. Reduces screen glare while keeping the room bright. Note: Priority depends on window orientation.

Kitchen

Take down: Heavy panels near heat-generating appliances. Put up: Short sheer panels or cotton voile: easy to wash, handles humidity well.

Kids' Room

Take down: Dark blackout curtains on sun-facing windows. Put up: White or pale blackout panels. Same darkness, far less heat.

What to Do If You Don't Want Two Sets of Curtains

Storing a second set is not always practical. Three approaches that work without replacing what you have.

Remove the Lining, Keep the Curtain

Most thermal and blackout liners clip or tie onto the curtain header. Remove the lining in summer and reattach it in fall. The panels stay the same; the insulation comes and goes. Works well with grommet, back tab, and pinch pleat curtains.

Add a Sheer Layer in Front

Hang a sheer panel on the inner rod, closest to the glass, and keep your existing heavier curtains on the outer rod. In summer, draw the sheers and push the heavier panels to the sides. The room stays bright; the heavy fabric stays out of the way.

Swap Panels on the Same Rod

If your curtains use grommet, rod-pocket, or back tab headers, swapping panels takes about ten minutes per window. Pinch pleat panels use hooks and can also be swapped: just reattach the hooks to the new panel before hanging. Tab top panels work especially well here since the loops slide on and off the rod with no hardware needed. Store the winter set in a labeled bag, hang the summer set, and reverse it in September.

How to Store Your Winter Curtains So They're Ready in Fall

Clean Before You Pack

Curtains collect dust, allergens, and cooking residue over months of use. Residues left in storage set permanently into the fabric. Wash or dry-clean based on the care label before packing anything away.

Make Sure Everything Is Dry

Pack curtains even slightly damp and you risk mold and permanent odor. Let them air out fully after washing before folding or rolling.

Roll Instead of Fold

Rolling around a cardboard tube distributes pressure evenly and prevents the sharp creases that folding creates, especially for velvet and lined fabrics.

Use Breathable Storage

Cotton bags or cotton pillowcases allow air circulation. Avoid sealed plastic bins for anything stored longer than a few weeks.

Label Each Set

Include the room, window location, and panel count. Rehanging six months later is much faster when you are not guessing which panels go where.

Refresh Your Windows This Summer

Sheer curtains change how a room performs through the hottest months: cooler air near the windows, softer light in the afternoons, and a space that feels open rather than closed off. It is a practical update with a result you notice the same day.

If you are ready to make the swap, Joydeco carries sheer curtains, light-filtering panels, and custom-sized options in a range of fabrics and heading styles, sized to fit your windows exactly.

Every panel is made to order. Bring your measurements and Joydeco's sizing guide handles the rest, so you get the right fit the first time without the guesswork.

FAQs

Q: Should you change curtains with the seasons?

It is not required, but it makes a real difference. Heavy winter curtains trap heat in summer. Swapping to sheer or light-filtering curtains improves airflow, reduces solar heat gain, and makes rooms feel cooler without changing your HVAC setup.

Q: What curtains are best for keeping heat out in summer?

Light-colored curtains in breathable fabrics. White or pale sheer curtains reflect solar radiation rather than absorbing it. For rooms needing both darkness and heat control, white or ivory blackout panels outperform dark-colored ones because they reflect heat instead of absorbing it.

Q: Should curtains be open or closed in summer to keep the house cool?

Closed on sun-facing windows during peak hours, open at night. South- and west-facing windows gain the most heat between 10am and 6pm. Closing curtains before the room heats up, even sheer panels, intercepts solar heat at the glass. After sunset, open everything to let cooler air in.

Q: What is the difference between summer and winter curtains?

Winter curtains are heavier, thicker, and lined to trap heat and block drafts. Summer curtains are lighter, more open in weave, and often unlined to allow airflow and reflect solar energy. Color matters too: light tones for summer, darker tones work better in winter.

Q: Can the same curtains work for both summer and winter?

Yes. A curtain with a removable thermal lining works in both seasons: take the lining out in summer, clip it back in fall. A sheer-and-blackout layered setup on a double rod also works year-round: sheers alone in summer, both layers in winter.