How to Stop Condensation on Windows: 19 Tips to Clear Things Up

A little condensation on your windows now and then isn’t a big deal, but over time, it can become more than a cosmetic nuisance. In fact, it can be a real problem, causing insulation issues, mold growth on windowsills, and even water damage to the windows. Knowing how to stop condensation on your windows is key to preserving your windows in the long term.

Condensation on the inside of windows occurs when there’s too much humidity or moisture in the air. That’s often when the air inside is warmer than outside (warm air contains more moisture) and that warm air comes into contact with colder surfaces, such as windows.

Below, we’ll walk you through 19 ways to prevent condensation from forming on the inside of your windows—plus what to do if there’s condensation between the window panes and what to do if there’s condensation outside your window.

1. Open Your Windows

In some cases, simply opening your windows to let outdoor air in will fix the issue. Condensation on the inside of windows forms when moisture in the air condenses on the glass. The reason this is commonly attributed to temperature differentials between the outside and inside air is that warm air holds more moisture than cold air. If warm, humid air suddenly drops in temperature, the moisture naturally falls out because the dew point is lower.

Opening your windows can fix this problem in a few ways:

• It lets indoor humidity escape. When you open windows in a home that’s warmer than the outside temperature, the warm air rushes out and brings some of that humidity with it. Reducing the humidity level will leave less moisture in the air to condense on the glass.

• It reduces the temperature in your living space. Similarly, that rush of warmth outside will bring cool air in, reducing the temperature inside. When the temperature differential on either side of the window is balanced, there’s less chance of moisture condensing on the glass.

• It introduces ventilation. Opening windows creates air movement inside, and moisture evaporates more readily in moving air.

2. Turn Down the Heat

Another way to stop condensation on the inside of windows is to lower your thermostat settings. The risk of condensation on the inside of windows is higher when the temperature difference on either side of the glass is larger. If you can drop the indoor temperature a few degrees and still maintain comfort, this might solve the issue or at least make the condensation less severe.

3. Run Your Ceiling Fans to Circulate Air

Increasing airflow throughout your home ensures that moist air can’t accumulate and eventually condense on the inside of your windows. An easy way to increase circulation in your home is to turn on the ceiling fans, even in winter.

Worried about being too cold in the winter with the ceiling fan on? You can actually change the direction the blades rotate to push warm air back down to the ground; it’s an effective way of warming a room without cranking the heat. Here’s how to change the direction of your ceiling fan.

4. Move Furniture Off Exterior Walls

When couches, dressers, beds, bookshelves, and wardrobes are pushed up against the wall, it can prevent warm air from properly circulating. Pull the furniture a couple of inches off the external walls to allow for airflow, and consider rearranging your room to place furniture against interior walls.

5. Open Interior Doors Throughout Your Home

You can increase airflow throughout your home—and thus reduce condensation on windows—by leaving doors wide open. This includes closet doors, too.

The exception? When bathing or cooking. Closing doors to the bathroom or kitchen when they’re in use can prevent moist air from traveling throughout the house.

6. Take Shorter, Cooler Showers

Nothing feels better than a long, hot shower, especially on a cold winter’s night. But the longer that shower, and the hotter, the more humidity you’re introducing into your home. And that humid air will result in condensation when it comes into contact with colder surfaces, like your windows.

In poorly ventilated bathrooms, you may even notice drops of water forming on your walls for the same reason.

7. Use Bathroom and Kitchen Fans

To reduce humidity in your bathroom and to keep the air circulating, always run the fan when showering. Similarly, if you have an exhaust fan in your kitchen, run this while boiling water, and use lids on top of your pots and pans to retain moisture. You should even run it when cooking or baking anything that will release a lot of moisture.

8. Turn Down (or Off) the Humidifier

You may run a humidifier if you or your children have colds or sinus issues, regular bloody noses, or dry skin and lips, but they can be a huge contributor to window condensation. After all, they’re putting moisture into the air intentionally.

Try turning down your humidifier to lessen its impact or, if possible, stop running it completely.

9. Use a Dehumidifier

You can even go a step further and run a dehumidifier in particularly damp areas, like your basement or a bathroom without a fan. You can run these when humidity levels in your home are high.

You can buy a small dehumidifier affordably (a couple hundred bucks for a larger, nicer model), but you can also have a larger system installed for your entire home. A whole-house humidifier costs between $1,300 and $2,800.

10. Relocate (or Remove) Plants

Plants release water vapor into the air in a process called transpiration. That means, while house plants are great for offering fresh air, they’re also increasing the humidity within your home.

Consider relocating plants that are causing issues for a window—but remember that some plants are finicky and don’t like to be moved, and most need at least indirect sunlight, so they can’t be placed too far from the window.

11. Install Curtains, Blinds, or Drapes

To prevent warmer interior air from contacting the window glass (and thus causing condensation), you can install blinds, drapes, or curtains to add as a buffer. These window treatments are also helpful in regulating interior temperatures in your home, which can reduce your heating and cooling costs.

12. Install Weather Stripping

Adding weather stripping to your doors and windows will help prevent cool air from entering your home in the winter; as cool air enters, it brings down the temperature of your exterior walls and your windows—thus making them susceptible to condensation when the rest of your home is warmer. Weather stripping costs an average of $275 per project.

You should also check to make sure your window seal isn’t broken. A broken window seal can lead to window condensation issues and drafts.

13. Install Storm Windows

Similarly, you can install storm windows as an extra barrier to keep cool air out in the winter. Storm windows also make your home more energy efficient.

Storm windows cost between $4,625 and $20,450 when installed throughout your home.

14. Check on Your Crawl Space 

If you have a dirt crawl space, lay down a plastic covering to trap moisture beneath it. You’ll also want to properly ventilate your crawl space.

15. Check the Venting of Your Washing Machine

Make sure your washing machine is properly vented so that it does not add moisture to the air when it runs. Here’s how to vent your washing machine yourself, but if you’re not up to the task, look for a well-reviewed washing machine contractor near you.

16. Hang-Dry Clothes Outside

Some clothes, towels, and bedding may shrink in the dryer, but hang-drying inside adds more moisture to the air—and increases the potential for condensation on the window.

If the weather is nice, hang your clothes outside instead.

17. Cover Your Fish Tanks

If you or your kids have an aquarium, make sure there is a lid on it at all times to retain the moisture. Keep the tank away from exterior walls and windows to reduce the amount of condensation buildup on the inside of your windows.

18. Use a Moisture Eliminator—or a Bowl of Salt

You can find moisture eliminator products, such as DampRid, at your local hardware stores, online, and even at some grocery stores. You simply set the bucket on the floor in high-moisture areas of your home, such as bathrooms and kitchens, and they’ll help keep the moisture at bay.

If you want to do it yourself, you can try placing a bowl of salt on the windowsill near windows that commonly get condensation. The salt absorbs moisture from the air, which in turn reduces condensation on the window.

19. Install an Air Exchange

If you’re researched how to stop condensation on windows and tried just about everything, you might need to try a larger solution, such as installing an energy recovery ventilator (ERV) to your HVAC system. This air exchanger keeps fresh air coming into your home and can ventilate out humid air. Expect to pay $2,000 or more; you’ll need to hire a local HVAC company for the installation.

What to Do If There’s Condensation Between the Window Panes

Condensation between the panes of glass in your window is a much bigger problem. Before assuming the worst, simply clean both sides of the window glass. It’s possible the glass has just grown dirty over time—regular window cleaning is important for clear views, energy efficiency, and glass degradation prevention.

However, if the window glass is clean and the problem truly is condensation between the window panes, you’ll need to contact a local window repair contractor. They’ll either need to replace individual panes of glass or, in some cases, replace the entire window. (To keep costs down, you can hire a handyman for window repair if it’s simple, but for larger repairs or replacement, we recommend a specialized window pro.)

If the window is otherwise still in good shape, the former option is ideal. Replacing window glass costs between $175 and $400 and general window repair costs $175 to $625, while replacing the entire window costs between $300 and $2,500.

What to Do If There’s Condensation on the Outside of Your Window

The good news is that condensation on the outside of your window is perfectly normal, and it’s not harming anything. In fact, it’s actually a sign that your windows are working properly.

The bad news: It can still be frustrating if you want beautiful views outside in the mornings while sipping your coffee.

Here’s what you can do:

Wait It Out

You can simply wait out the morning dew, which should evaporate as things warm up. But if you want to speed up the process, you can raise the temperature on your AC to warm up the window glass (exterior condensation is more common in the summer months).

Trim Your Trees and Shrubs

You can also trim back any shrubs and trees near the windows to increase circulation and reduce humidity. Trimming plant life near your home serves other purposes, like protecting your home during storms and keeping pest problems to a minimum.

Use a Water Repellant

If you’re not keen on warmer interior temperatures but still want to avoid outside window condensation, spray a water repellent on the outside surface of the glass and wipe it clean. You’ll have to reapply it regularly as part of your routine window maintenance to keep the glass clear, but it’s an easy way to stop condensation on windows.

Most products made for car windshields should be safe for home windows, too, but you might want to speak with a local window expert to confirm before using them.