At NorthShield Windows and Doors, we can know a lot about doors and windows. When it comes to unit replacement, your options basically come down to two possibilities. You can choose between single-hung units, or you can opt for double-hung units. Each type has its own strengths and potential drawbacks. You will definitely need to make sure you are dealing with something that is going to meet your needs for a long time. After all, when we are talking about units, it makes sense to want to do the right amount of research. If you have never gone shopping for units before, relax. We can give you all the basics you need to make sure you are getting the perfect units for your specific taste and requirements. The major question you want to answer right away is whether to install single-hung or double hung units.