Why Do My Windows Fog in the Winter?
It’s a familiar scene during winter. You walk to your car to find the windows are all fogged up or iced over. You grab the ice scraper and get to work, or perhaps you hit the defrost button and patiently wait as the fog dissipates.
But what to do when your home windows fog up? There’s no defrost button that you can hit to get rid of the cloudy condensation. Not to worry. Entek has seven decades of experience in the industry and our certified HVAC professionals understand how to improve a home’s air quality. We’ll explain exactly what causes windows to become foggy and just how to fix the problem.
The good news is that while foggy windows may seem to be an inconvenience, they are a way for you to confirm that your energy-efficient home windows are working. The first thing to understand is that home windows fog up for the same reason that car windows do. When warm moisture comes into contact with a cold surface, condensation occurs. Moisture can be produced in your home in a variety of ways — from normal breathing to everyday activities like cooking and taking a shower.
Your energy-efficient windows are preventing that moisture from escaping your home, thereby lowering your heating and cooling costs. And since windows and window metal frames are often the coldest surfaces in our home, it’s the place where the condensation is most likely to form.
However, if you see condensation form between the panes of glass rather than on the outside surface, it’s a sign that your windows are not working and you may need to consider upgrading to newer, energy-efficient ones.
So now that you understand how and why the fog occurs, what can you do to fix it? There are a number of solutions, but one of the simplest steps you can take is to regulate the thermostat temperature in your home.
Maintaining your home’s thermostat at a constant temperature helps prevent condensation from forming on the windows. One way to ensure that your home stays at a constant temperature is by using a programmable thermostat. Programmable thermostats will control your thermostat temperature even when you’re away so you won’t have to constantly monitor it.
For most homeowners, this quick fix will do the trick. However, if you notice the problem persists, you may have a more serious issue that requires further attention. In order to correct this, you’ll want to reduce moisture levels and raise the temperature of your home’s window glass. So how exactly do you do that?
Condensation forming on your windows is likely a sign that there are high humidity levels in your home. You should monitor the level of humidity and adjust it accordingly. The correct humidity level for your home will depend on a number of factors including the outside air temperature, the inside air temperature, and your particular window type.
For example, if you have double-glass windows, an interior home temperature of 70 degrees, and an outdoor air temperature of 20 degrees, you should have a humidity level no greater than 40%. That percentage will drop as the outdoor air temperature drops. However, if you have energy-efficient windows, the glass temperature will be warmer and your humidity level can be higher. If you have a humidifier, be sure to check it regularly to make sure it’s not adding too much moisture to your home.
You’ll also want to make sure your home is properly ventilated. As mentioned, there are several moisture sources in your home such as bathing, showering, and cooking. You’ll want to make sure that you’re running the ventilation fans in each of these rooms. If you step out of a hot shower, you may notice that the bathroom mirror has steamed up. Running the fan will help to prevent this. Likewise, running the exhaust fan in your home’s kitchen will help to ventilate that room as well. Both of these are examples of what is known as point-source ventilation, removing moisture in your home at specific sites.
Occasionally, however, you’ll also need to ventilate the structure of your home. You can do this through your home’s attic. First, go up to the attic and take a look around. You should be able to see vents in the roof of the attic or in the eaves. If you do not see any, you’ll need to add some. You should also notice an absence of moisture such as mildew or ice crystals. If you do happen to see that mildew or ice crystals are present, you may need to contact a professional to determine if your home needs better ventilation. At Entek, our certified professionals will assess your home’s air quality and ventilation to prevent negative impacts on your health and improve your home’s energy efficiency.
It’s fairly normal for windows to fog up in the winter, especially in newly constructed homes that are designed to be energy-efficient. However, if you notice a persistent problem with foggy windows, you’ll likely want to contact a professional to see if it’s time to order replacements. Energy-efficient windows will help lower your electric bill by reducing your home heating and cooling costs. For some good tips on how to select the right type of energy-efficient windows, look here.
While foggy windows by themselves aren’t cause for concern, a persistent problem can cause mold, mildew, and even structural damage to your home. If you believe your windows aren’t operating properly, air quality experts can assess your home and make recommendations that will improve your comfort, health, and energy efficiency. We’ll provide the proper solution for defogging your windows so that you can simply sit back, relax, and enjoy your new clear view.
