When it’s cold outside, and warm inside, and when there is moisture in the air inside, from say, breathing out, then you can bet that condensation will start to build up on your windows. There are ways to stop it however, if you’re not a fan of all that water building up on your windows.
There are a couple of reasons that people want to get rid of condensation buildup on their windows in the winter months. The first is that if it builds up enough, it can start to run down the window and onto your sill, which can cause your sill to rot. Another reason is that it can contribute to mold.
To stop condensation, or reduce it, you can attack the problem from two ways. The first is to reduce the amount of moisture that is in the air. This can be done by purchasing a dehumidifier, which can then be set close to the window. Many people will find this impractical though, because humidifiers are usually only used in the summer months when it’s hot and humid out. The other way is to convert your home heating system from electric to gas. Natural gas heating systems are notorious for burning so much water out of the air that homes become too dry. Again though, most people will find this a bit extreme.
Thus, your best approach is to generally attack the moisture problem where it actually occurs, and that is on your windows.
For the most part, you have two options. The first is to buy yourself some of the clear window covers that are now available for just this purpose. It looks pretty much just like the clear kind of Saran Wrap and comes on a roll or in sheets. What you do is put this stuff over your window, and then use a hair drier to make it stick tightly to your frame, thus sealing off any fresh air being able to come into contact with the window. Do this to all of the windows in your house that have a condensation problem, and your problem will be solved. One very surprising thing about using this kind of window sealer is just how invisible the material is once you’ve used the hair drier on it. In most cases, you won’t even be able to tell that it is there unless you come right up to the window and have a close look.
Your other option is to replace your windows with double paned glass; doing so will work and will be a permanent fix; though it will cost a lot more than the simple window sealer.