Should You Keep Curtains Open or Closed in Winter?

Open curtains on a sunny winter window

 Should you keep your curtains open or closed when it's cold outside?

The simple answer is both, but at different times.

On sunny winter days, opening curtains on windows that receive direct sunlight can let solar heat into your home. Once the sun goes down, closing curtains and blinds can help reduce the discomfort you feel near cold windows.

A good starting point is simple: open curtains when useful sunlight is coming in, and close them when it isn't.

However, window direction, drafts, condensation, and the type of curtains you have can all affect what works best.

Should Curtains Be Open or Closed During the Day?

If direct winter sunlight is reaching a window, opening the curtains can be useful.

The U.S. Department of Energy recommends opening curtains on south-facing windows during winter days to allow sunlight to naturally warm the home.

Think of sunlight as free heat.

When direct sunlight passes through the glass, it can warm surfaces and objects inside the room. Keeping a thick curtain closed over a sunny window may block some of that useful solar gain.

So, on a bright winter morning or afternoon, check which windows are actually receiving direct sunlight and open those curtains.

There is no need to open every curtain in your home just because it's daytime.

What About Windows That Don't Get Sun?

This is where the advice becomes more practical.

A window that receives little or no direct winter sun isn't providing the same solar-heating benefit.

For example, north-facing windows in the Northern Hemisphere generally receive much less direct winter sunlight than south-facing windows.

If a particular window feels noticeably cold and doesn't receive useful sunlight, keeping an insulating curtain or shade closed may make the area around it feel more comfortable.

ENERGY STAR recommends thermal curtains as one option for reducing winter heat loss through north-facing windows, while curtains on south-facing windows can be opened during the day to take advantage of sunlight.

The important point is that you don't have to treat every window the same way.

Pay attention to what the sun is actually doing in your apartment.

Open and closed curtains on winter windows

Should You Close Curtains at Night in Winter?

Generally, yes.

Once the sun has gone down, you're no longer getting useful solar heat through the window.

At that point, closing curtains, blinds, or shades adds another layer between the occupied room and the cold window.

The Department of Energy recommends closing curtains at night to reduce the chill you may feel from cold windows.

This can be particularly noticeable if your bed, sofa, desk, or dining table is close to a large window.

Even when the thermostat says the room is warm enough, sitting next to a cold window can make you feel less comfortable.

Closing the curtains can help.

Do Curtains Actually Keep a Room Warmer?

Curtains don't generate heat, and they can't repair a poorly insulated window.

What they can do is provide an additional layer at the window and help reduce heat transfer and discomfort.

The effect depends heavily on the window and the type of covering.

A thin decorative curtain won't perform like a properly fitted insulating shade or thermal curtain. Curtains that leave large gaps around the window may also provide less benefit than coverings that fit more closely.

So don't assume that every curtain provides the same level of insulation.

The simplest approach is to use your existing curtains strategically before buying anything new.

What Are Thermal Curtains?

Thermal curtains, sometimes called insulated curtains, are designed with thicker or multiple layers intended to provide more insulation than lightweight decorative curtains.

They can be particularly useful around windows that feel cold during winter.

ENERGY STAR lists thermal curtains as one option for reducing heat loss through north-facing windows during colder months.

But you don't necessarily need to replace every curtain in your apartment.

Start with the coldest or draftiest window.

If one bedroom window makes the area around your bed noticeably uncomfortable, improving that single window covering may be more useful than buying matching thermal curtains for the entire apartment.

What If Your Windows Are Drafty?

Curtains can improve comfort, but they shouldn't be confused with air sealing.

If cold air is physically entering around the window frame, you have an air-leak problem.

You may notice the curtain moving slightly even though the window is closed, or you may feel a stream of cold air when you hold your hand near the frame.

In that situation, the curtain is treating a symptom rather than the source.

Depending on your rental agreement and the condition of the window, renter-friendly options may include approved weatherstripping, removable window treatments, or asking your landlord or property manager to address a damaged window or seal.

If you're renting, avoid making permanent modifications without checking what your lease allows.

Be Careful If You Have Window Condensation

There's another winter curtain problem that's easy to overlook.

If your windows regularly collect condensation, keeping heavy curtains tightly closed for long periods can make it easier to overlook moisture accumulating behind them.

Check behind the curtains regularly.

If water is collecting on the glass, frame, sill, or nearby wall, don't simply hide it behind the curtain.

Wipe up the moisture and investigate why the condensation is occurring.

Indoor humidity, ventilation, outdoor temperature, window performance, and indoor temperature can all affect condensation.

Curtains may make a cold window area more comfortable, but they aren't a solution for persistent moisture problems.

Should Curtains Touch a Radiator or Heater?

Avoid arranging curtains where they interfere with heating equipment.

If your apartment has a radiator, baseboard heater, floor vent, or another heat source near a window, make sure the curtain isn't blocking airflow or resting against a hot surface.

The appropriate clearance depends on the heating equipment, so follow the manufacturer's instructions and any building safety requirements.

You want warm air to circulate into the room rather than become trapped behind a curtain.

If closing your curtains completely blocks a heating vent, adjust the curtain arrangement instead of covering the heat source.

What About Blinds?

Blinds can also be used strategically during winter.

The same basic routine applies: let useful sunlight enter when it's available, then close the window covering after sunset.

However, different types of blinds and shades provide different levels of insulation.

Basic horizontal blinds used mainly for privacy aren't necessarily equivalent to an insulated cellular shade or a thermal curtain.

If you're working with whatever is already installed in a rental, that's fine.

You don't need a perfect window-treatment system to develop better winter habits.

A Simple Winter Curtain Routine

You don't need to constantly adjust every curtain in your apartment.

Try a simple routine.

Morning: Check which windows are receiving useful direct sunlight and open those curtains.

During the day: Leave sunny windows uncovered while the sunlight is helping warm the room.

Late afternoon: As direct sunlight disappears, start closing the curtains.

Night: Close curtains and blinds, particularly over windows that feel cold.

Next morning: Check for condensation before opening the curtains again.

After a few days, the routine becomes almost automatic.

Should You Open Curtains When You Leave for Work?

It depends on whether the window will receive useful sunlight while you're away.

If you have a south-facing living room that receives several hours of winter sun, leaving the curtain open can allow that solar energy into the room.

If a window remains shaded all day, there may be little reason to leave an insulating curtain open simply because it's daytime.

Privacy and security also matter.

If opening a curtain exposes your apartment to a busy street or neighboring building, you don't have to sacrifice privacy for a modest potential heating benefit.

Use the strategy where it makes practical sense.

What If Your Apartment Gets Too Warm in Direct Sun?

It can happen.

A sunny room with large windows may become surprisingly warm even on a cold winter day.

If the room becomes uncomfortable, partially close the blinds or curtains rather than continuing to collect heat you don't need.

The goal isn't to maximize solar heat at all costs.

It's to use available sunlight when it helps you stay comfortable without unnecessary heating.

Common Winter Curtain Mistakes

One common mistake is keeping every curtain closed all winter because curtains provide insulation.

That can mean missing useful solar heat on sunny windows.

The opposite mistake is leaving every curtain open day and night. Once the sun disappears, you're no longer gaining that solar warmth.

Another mistake is expecting curtains to fix serious drafts. If outdoor air is entering around a damaged or poorly sealed window, addressing the air leak is more important.

Finally, don't ignore condensation simply because it's hidden behind a closed curtain.

Check your windows regularly during cold weather.

Frequently Asked Questions

Is it better to keep curtains closed in winter?

Not all the time. Open curtains on windows receiving useful direct sunlight during the day, then close them when that sunlight is gone. Windows that receive little winter sun may benefit from keeping insulating coverings closed more often.

Should I close my curtains every night?

Generally, yes. Closing curtains or blinds at night can help reduce discomfort near cold windows when there is no longer useful solar heat coming through the glass.

Do open curtains make a home warmer in winter?

They can when direct sunlight is entering through the window. Opening curtains allows that solar energy into the room. Opening curtains on a completely shaded window doesn't provide the same benefit.

Are thermal curtains useful in an apartment?

They can be useful around particularly cold windows, especially when replacing the window isn't an option. Before buying them for every room, consider starting with the window causing the most discomfort.

Should I close curtains if my windows have condensation?

Curtains aren't a solution for condensation. If moisture regularly forms on the glass or frame, monitor and remove it and address the underlying moisture conditions rather than allowing persistent condensation to remain hidden behind heavy curtains.

Final Thoughts

The best winter curtain strategy isn't simply open or closed.

It's about timing.

Open curtains when useful winter sunlight is coming through the window. Close them after the sunlight disappears.

For windows that receive little direct sun, insulating curtains may be more useful when kept closed during colder periods.

And if you're dealing with serious drafts or persistent condensation, treat those as separate problems rather than expecting curtains to solve them.

A simple daily curtain routine can help you make better use of the warmth that's already available in your apartment.