How to Stop Condensation on Apartment Windows in Winter

 You wake up on a cold morning and your apartment windows are covered in water. Maybe the glass is foggy, droplets are running down the pane, or there is enough moisture to leave a puddle on the windowsill.

Window condensation is common during cold weather, but that does not mean you should ignore it.

The good news is that you usually do not need to replace a window or make permanent changes to a rental. The most effective approach is to reduce excess indoor humidity, improve airflow around the window, and keep moisture from sitting on the glass and frame.

Here is how to figure out what is causing the condensation and what you can do about it as a renter.

Condensation on an apartment window in winter

Why Do Apartment Windows Get Condensation in Winter?

Condensation forms when warm, moisture-containing indoor air comes into contact with a surface cold enough for the water vapor to turn into liquid.

In winter, window glass is often one of the coldest surfaces in an apartment. That makes it an obvious place for condensation to appear.

The U.S. Environmental Protection Agency (EPA) notes that condensation can be a sign of high indoor humidity and recommends controlling both moisture and airflow to help prevent it.

Everyday activities can add moisture to your apartment, including:

• showering
• cooking and boiling water
• drying laundry indoors
• using a humidifier
• washing dishes
• certain unvented appliances

The colder the window surface becomes, the easier it is for moisture in the indoor air to condense on it.

That is why a window can be dry in October but covered in droplets on a much colder January morning.

First, Check Where the Water Is

Before trying to fix the problem, look closely at where the condensation appears.

Moisture on the inside surface

If you can wipe the water away from inside your apartment, indoor humidity and the cold window surface are usually involved.

This is the type of condensation you can often reduce yourself.

Moisture between the panes

Water or fog trapped between two panes of glass is different.

You cannot simply wipe it away because the moisture is inside the window assembly. This can indicate a problem with the insulated glass seal.

As a renter, document the problem and contact your landlord or property manager rather than trying to disassemble or permanently repair the window yourself.

Water around the frame or wall

Do not automatically assume that every wet window is condensation.

Water stains, bubbling paint, wet drywall, or moisture that appears during rain can point to a leak instead.

If you are not sure where the water is coming from, take photos and report it rather than covering it up.

1. Measure Your Apartment's Humidity

Hygrometer beside a window with condensation

A small digital hygrometer can make troubleshooting much easier.

Instead of guessing that your apartment "feels humid," you can see the relative humidity level and watch how it changes after showering, cooking, drying laundry, or running a humidifier.

The EPA recommends keeping indoor relative humidity below 60% and ideally between 30% and 50% when possible.

During cold heating seasons, the appropriate level may need to be toward the lower end of that range. ENERGY STAR notes that in colder climates, roughly 30% to 40% relative humidity during heating season can help prevent window condensation.

There is no single perfect number for every apartment. Outdoor temperature, window quality, insulation, ventilation, and indoor temperature all affect when condensation begins.

Use the hygrometer as a diagnostic tool rather than treating one number as a universal rule.

2. Use the Bathroom Fan When You Shower

A hot shower can release a significant amount of moisture into a small apartment.

If your bathroom has an exhaust fan that vents outdoors, turn it on when you shower and leave it running afterward.

ENERGY STAR recommends using bathroom and kitchen fans during moisture-producing activities and continuing ventilation after you finish.

If you do not have a working bathroom fan, use whatever ventilation your apartment safely provides, such as opening a window when outdoor conditions make that practical.

And if the bathroom exhaust fan does not work, that is worth reporting to maintenance rather than simply accepting a permanently humid bathroom.

3. Use the Kitchen Exhaust Fan When Cooking

Cooking can be another major source of indoor moisture.

Boiling pasta, making soup, simmering food, or repeatedly boiling a kettle releases water vapor into the air. In a small apartment, that moisture can spread quickly into other rooms.

Use a range hood or kitchen exhaust fan if yours vents outdoors.

Covering pots when practical can also reduce the amount of steam released into the room.

If your windows always become wetter after dinner, cooking moisture may be part of the problem.

4. Be Careful When Drying Laundry Indoors

An indoor drying rack may save money and be necessary in some apartments, but the water leaving those clothes has to go somewhere.

It goes into the air.

If you regularly dry wet laundry inside and also struggle with window condensation, pay attention to your humidity readings on laundry day.

Increase ventilation when practical, avoid placing wet clothes directly beside a cold window, and consider using a dehumidifier if indoor drying repeatedly pushes humidity too high.

The same principle applies to a clothes dryer: if your apartment has one, it should be properly vented according to the appliance and building setup. EPA guidance specifically identifies moisture-generating appliances as something that should be vented outdoors where possible.

5. Turn Down the Humidifier

A humidifier can make dry winter air more comfortable, but it is possible to add too much moisture.

If you see heavy condensation while a humidifier is running, check the humidity level before assuming that your apartment needs even more moisture.

Try reducing the setting or temporarily turning the humidifier off and watch what happens to the windows.

A humidifier and a cold window can work against each other: one adds moisture while the other provides a cold surface for that moisture to condense on.

6. Improve Airflow Around the Window

Sometimes the overall humidity level is reasonable, but the air immediately around the window stays cold and stagnant.

Heavy curtains, tightly closed blinds, or furniture pushed against a window can limit air movement.

ENERGY STAR specifically recommends window treatments that allow airflow over the window surface as one way to reduce condensation risk.

Try opening curtains or blinds periodically and avoid completely trapping the window behind furniture.

A small amount of improved air circulation can help keep the inside surface warmer and reduce localized moisture buildup.

7. Ventilate When Outdoor Conditions Make Sense

Opening a window for a short period can help when the outdoor air is cold and relatively dry.

The goal is not to leave your apartment freezing all day. It is to replace some moisture-heavy indoor air with drier outdoor air when conditions allow.

EPA guidance lists increased ventilation as one way to reduce condensation and humidity.

Ventilation can be particularly useful after activities that create a lot of moisture, such as showering or cooking.

However, opening windows is not automatically helpful in every climate or weather condition. If the outdoor air itself is very humid, ventilation may not solve the problem.

8. Consider a Dehumidifier for Persistent Humidity

If ventilation and moisture control are not enough, a dehumidifier may help.

This is especially useful when your apartment consistently stays humid because of limited ventilation, indoor laundry, or other unavoidable moisture sources.

Choose a unit appropriate for the space rather than assuming the smallest model will handle an entire apartment.

Many modern dehumidifiers include a humidistat, allowing the machine to cycle on and off around a selected relative humidity level. ENERGY STAR recommends considering capacity, energy efficiency, and the conditions of the space when choosing one.

Before buying anything, however, spend a few days measuring the humidity.

If your apartment is already at a relatively low humidity level and one particular window is still soaking wet, the window itself may deserve closer attention.

9. Wipe Up Condensation Instead of Letting It Sit

Reducing future condensation is important, but deal with the water that is already there too.

Wipe wet glass and windowsills with a clean, absorbent cloth and allow the area to dry.

Do not leave towels permanently stuffed against a wet frame. Once a towel becomes damp, it can simply hold moisture against the surface.

This matters because persistent moisture can create conditions where mold grows.

The EPA recommends drying wet or damp materials quickly—ideally within 24 to 48 hours—and emphasizes that moisture control is the key to controlling indoor mold.

10. Consider Renter-Friendly Window Insulation

If a particularly cold or drafty window repeatedly develops condensation, improving its insulation may help.

Temporary interior window film is one renter-friendly option, provided your lease allows it and the product is suitable for the window and frame.

ENERGY STAR notes that properly installed plastic window film can reduce drafts and moisture buildup from condensation while adding an insulating air layer.

This approach can be especially useful with older windows.

Just remember that insulation is not a substitute for managing excessive indoor humidity. If your apartment is consistently too humid, deal with the moisture source as well.

What Not to Do About Window Condensation

A few quick fixes can hide the symptom without addressing the cause.

Do not keep increasing the heat solely to dry the window. Temperature matters, but persistent excess moisture still needs to be addressed.

Do not run a humidifier blindly. Check the actual relative humidity first.

Do not ignore standing water. Dry the glass and frame rather than allowing water to remain there day after day.

Do not permanently seal or modify a rental window without permission. A failed seal, damaged frame, leak, or installation problem belongs in a maintenance request.

And do not assume visible moisture is always normal condensation. A building leak needs a different solution.

When Should You Contact Your Landlord?

Occasional light condensation on a very cold morning does not necessarily mean the window is defective.

But some situations deserve a maintenance request.

Contact your landlord or property manager if you notice water trapped between panes, obvious gaps or damage around the frame, water entering during rain, persistent wet drywall, peeling or bubbling paint, recurring mold, or condensation so severe that water repeatedly pools around the window despite reasonable humidity control.

Take photos before cleaning the area, especially if the problem keeps returning.

It can also help to record your indoor humidity readings. Saying, "This window is wet every morning even when the room is around 35–40% RH" gives maintenance more useful information than simply saying the room feels damp.

Can Window Condensation Cause Mold?

Condensation itself is water, not mold.

The concern is what happens when surfaces stay damp.

Mold can grow when sufficient moisture remains available, which is why the EPA emphasizes fixing moisture problems and drying wet areas promptly.

Pay particular attention to:

• window seals
• painted or wooden sills
• drywall around the frame
• curtains touching wet glass
• carpet below the window

If you repeatedly wipe away water but never reduce the underlying moisture, the problem is likely to return.

A Simple Morning Routine for Wet Windows

If you regularly wake up to condensation, keep the routine simple.

First, wipe the glass and sill dry. Then check your hygrometer.

Think about what added moisture the previous evening: a shower, cooking, laundry, or a humidifier.

Ventilate if outdoor conditions are suitable, use your exhaust fans, and give the window some airflow by opening curtains or blinds.

After a few days, you may start seeing a pattern.

That pattern is far more useful than trying random fixes one at a time.

Frequently Asked Questions

Is condensation on apartment windows normal in winter?

Some condensation can occur when warm indoor air meets very cold window glass. However, heavy or persistent condensation should not simply be ignored, especially if water pools on the frame or nearby surfaces.

What humidity should my apartment be in winter?

EPA guidance recommends keeping indoor relative humidity below 60% and ideally between 30% and 50%. ENERGY STAR notes that colder climates may require approximately 30–40% RH during the heating season to help prevent window condensation.

Will a dehumidifier stop window condensation?

It can help when excess indoor humidity is a major cause. But condensation can also be affected by window temperature, insulation, outdoor conditions, and airflow, so a dehumidifier is not guaranteed to solve every window problem.

Should I open my windows in winter to stop condensation?

Short-term ventilation can help when outdoor air is cold and dry because it allows humid indoor air to escape. You do not necessarily need to leave windows open for long periods.

Should I tell my landlord about condensation?

Report it if moisture is trapped between panes, you suspect a leak, the window or frame appears damaged, mold repeatedly returns, or water continues to accumulate despite reasonable humidity and ventilation measures.

Final Thoughts

Stopping apartment window condensation is usually less about one magic product and more about controlling moisture.

Start by measuring indoor humidity. Use bathroom and kitchen ventilation, watch moisture from laundry and humidifiers, improve airflow around cold windows, and dry condensation instead of letting it sit.

If one window remains unusually wet while the rest of the apartment seems normal, document it. At that point, the problem may require your landlord or maintenance team rather than another renter DIY fix.

Keeping the glass clear is useful, but the bigger goal is simple: keep excess moisture from lingering long enough to damage the apartment or create conditions for mold.

How to Keep a Drafty Apartment Warm Without Turning Up the Heat

 A drafty apartment can feel cold even when the heat is running.

Cold air may be sneaking in around a window, a gap under the front door may be letting in a steady draft, or one room may simply feel much colder than the rest of the apartment.

Turning up the thermostat can help, but it doesn't solve the underlying problem. If warm air is escaping and cold air is getting in, you may just end up running the heat longer.

The good news is that renters still have options. Start by finding where the cold air is coming from, then use simple, reversible fixes to make the apartment feel warmer.

Warm living room in a drafty apartment

1. Find the Draft Before You Try to Fix It

Don't start by buying thermal curtains, window film, and draft stoppers for the entire apartment.

First, figure out where the cold spots actually are.

On a cold or windy day, slowly move your hand around the edges of windows and exterior doors. Pay attention to window frames, the bottom of doors, and anywhere you can visibly see a gap.

ENERGY STAR notes that noticeable drafts, rattling windows, and visible gaps around window or door trim can be signs of air leakage.

You may discover that one window is responsible for much of the discomfort.

That's useful because you can fix the biggest problem first instead of trying to warm the entire apartment.

2. Stop Cold Air Coming Through the Windows

Windows are one of the first places to investigate in a drafty apartment.

If you can feel cold air around the frame, check whether the window is fully closed and locked. A window that looks closed may not be sealing tightly.

For gaps around movable parts of a window, removable weatherstripping may help if your lease allows it. The U.S. Department of Energy specifically recommends weatherstripping around windows and doors as one way renters can reduce air leaks.

If the entire window feels like a source of cold, a temporary interior window-film kit is another option worth considering.

ENERGY STAR describes shrink-to-fit plastic window coverings as an inexpensive way to reduce drafts and help rooms feel warmer during winter.

Just remember that rental rules vary. Avoid permanent modifications unless you have permission from your landlord or property manager.

3. Block the Gap Under a Drafty Door

Sometimes the problem is much easier to see.

If there's a noticeable gap under your apartment door, cold air from an exterior hallway, stairwell, or outdoors may enter underneath it.

A draft stopper is one of the simplest renter-friendly solutions.

Place it along the bottom of the door when it's closed. There are commercial versions available, but the important part is simply creating a barrier against the moving air.

DOE includes draft stoppers among its suggestions for renters dealing with air leakage around doors.

If there is a large permanent gap, damaged weatherstripping, or a door that doesn't close properly, report it to your landlord rather than trying to rebuild or permanently alter the door yourself.

4. Use Your Curtains Differently During the Day and Night

Curtains can do more than provide privacy.

On sunny winter days, open curtains or blinds on windows receiving direct sunlight. The sun can provide some free warmth.

Once the sun goes down, close them again.

ENERGY STAR recommends opening drapes during daylight hours in cold weather to take advantage of the sun's warmth. DOE guidance also recommends window coverings to help retain warmth during winter.

Thicker curtains can also make the area near a cold window feel more comfortable.

But there's an important detail: don't let curtains block heating vents, radiators, or other heat sources.

You want to reduce the effect of the cold window without trapping the heat where it can't circulate through the room.

5. Make Cold Floors More Comfortable

Sometimes your apartment isn't especially drafty at eye level, but the floor makes the whole room feel cold.

This is particularly noticeable with tile, laminate, hardwood, or floors above unheated spaces.

A rug won't repair missing insulation underneath the building, but it can make the room much more comfortable to walk and sit in.

Focus on the places where you actually spend time: beside the bed, under your desk, near the couch, or in the main living area.

You don't necessarily need wall-to-wall coverage.

The goal is comfort, not rebuilding the apartment.

6. Don't Accidentally Block the Heat You Already Have

Before trying to create more warmth, make sure you're not preventing your existing heating system from doing its job.

Look around the room.

Is a couch sitting directly in front of a heating vent? Is a long curtain covering a radiator? Is furniture blocking a return vent?

If so, rearranging the room may help warm air circulate more effectively.

If your system has an accessible air filter that tenants are responsible for maintaining, check the lease or manufacturer's instructions to see whether it needs cleaning or replacement. DOE includes regular filter maintenance among its renter energy-efficiency recommendations because proper airflow matters for heating and cooling performance.

Don't open, modify, or attempt to repair heating equipment yourself.

If the heating system isn't working properly, that's a maintenance issue.

7. Warm the Space You're Actually Using

If you're spending the evening in the living room, it doesn't make much sense to focus your comfort efforts on an unused bedroom.

Close exterior doors and obvious sources of drafts, use rugs where you spend time, close curtains after sunset, and arrange the room so you're not sitting directly beside the coldest window.

Even moving your desk or favorite chair away from a cold exterior wall or inefficient window can make a noticeable difference in comfort.

ENERGY STAR points out that cold interior window surfaces themselves can make a person sitting nearby feel chilly, even when the room's thermostat reading seems reasonable.

That's an important distinction.

Sometimes the solution isn't making the entire apartment hotter. It's making the part of the apartment you're using more comfortable.

8. Pay Attention to Uneven Temperatures

One cold room doesn't necessarily mean you need a higher thermostat setting.

If the living room feels comfortable but the bedroom is consistently freezing, investigate why.

Check for:

• a particularly drafty window
• damaged seals around an exterior door
• blocked heating vents
• a vent that doesn't appear to be working
• unusually cold exterior walls or floors

ENERGY STAR lists drafts and uneven hot or cold rooms among signs that a home's performance may need attention.

If basic renter-friendly fixes don't help, document the problem and contact your landlord or property manager.

9. Know When a Draft Is a Maintenance Problem

Not every cold apartment can—or should—be fixed with curtains and weatherstripping.

A renter-friendly fix makes sense for a small draft. It doesn't make sense for a window that won't close, damaged frames, major gaps, a malfunctioning heating system, or persistent indoor temperatures that may violate local housing requirements.

Take photos of visible damage and note where and when the problem occurs.

Then report it through whatever maintenance process your building uses.

This is especially important if you notice moisture problems around windows. Condensation can have several causes, and ENERGY STAR recommends managing indoor humidity and maintaining appropriate ventilation rather than simply sealing everything indiscriminately.

Air sealing can also affect indoor air quality and combustion safety in some homes, so substantial sealing work belongs with the property owner or a qualified professional rather than becoming an improvised renter DIY project.

What Should You Try First?

If your apartment feels cold, don't tackle everything at once.

Start with this order:

1. Find the coldest window or door.
2. Block obvious drafts with renter-safe methods.
3. Open curtains for useful sunlight and close them after dark.
4. Make sure furniture and curtains aren't blocking your heat.
5. Use rugs and room layout to improve comfort where you spend the most time.
6. Report structural or heating problems that simple fixes can't solve.

This approach is usually more useful than immediately raising the thermostat because you're addressing the places where comfort is being lost.

FAQ

Why is my apartment cold even when the heat is on?

Drafts, cold window surfaces, blocked vents, uneven heating, or problems with the building envelope can all make an apartment feel colder than the thermostat suggests. Start by checking windows and exterior doors and making sure heating vents aren't blocked.

How can I stop cold air from coming through apartment windows?

If your lease permits it, removable weatherstripping can help with air leaks around movable window parts. Temporary interior window film can also reduce drafts. If the window is damaged or won't close properly, report it to your landlord rather than trying to make a permanent repair yourself.

Do thermal curtains really help a cold apartment?

Window coverings can help retain warmth and reduce discomfort near cold windows. Open them when useful winter sunlight is coming through, then close them after sunset.

How can I make my apartment warmer without spending much money?

Start with the free fixes: identify the draft, fully close and lock windows, move furniture away from heating vents, use sunlight during the day, and close curtains at night. Then consider inexpensive renter-friendly options such as a door draft stopper, removable weatherstripping, or temporary window film where appropriate.

Should I tell my landlord if my apartment is very drafty?

Yes, particularly if windows or doors are damaged, won't close properly, have significant gaps, or the heating system isn't maintaining adequate warmth. Small comfort improvements are one thing; building and heating-system defects are different.

Final Thoughts

A drafty apartment doesn't always need more heat. Sometimes it needs fewer places for warmth to escape and fewer cold spots around the areas where you actually live.

Start with the worst window or door, use reversible renter-friendly fixes where appropriate, take advantage of sunlight during the day, and keep your existing heat from being blocked.

And if the problem is bigger than a minor draft, involve your landlord rather than trying to turn a building problem into a DIY project.