Casement windows have traditionally been one of the most popular design used in house construction throughout much of Europe, and they remain popular there today. Houses are still being built in parts of Scandinavia which make extensive use of this type of window, and there are many more properties which are being renovated which still use them. They can be made to close effectively to keep out drafts and to prevent heat from escaping, and they can be secured against intruders.
The casement window is characterized by the hinges which can be found down one side of the frame. These hinges allow the window to open inwards, giving the home occupier the chance to let in air on hot days, as well as the chance to deposit items out of the window should it be appropriate to do so. If the windows are large enough, they can even be a way to enter and leave the room, as with some larger picture windows. This is not typical, though, and most casement windows are designed for ventilation. A variation of the casement window is the one which has the hinge at the top and opens outwards, and these are known as awnings. Because the fastener is at the bottom and more easily reached, these can be more of a security risk.
As a casement window is usually from an era before modern Low-E glass was developed, they are typically not optimized for insulation. They can be double glazed, although few of the early examples were. If you have windows which are not double glazed, fitting this enhancement will be one relatively cheap way of improving the effectiveness of the windows without needing to break the bank for a full refit and replacement. There is also no reason why Energy Star glass could not be fitted in these older windows, and this may be cost effective in colder climates.
The issue of security with casement windows is always there, as they offer two potential methods of entry to intruders. The first and most obvious way is the crude method of simply breaking the glass and climbing through, while the other is to somehow get to the handle which opens the door. This is often done by breaking a small section of the glass and reaching inside. The only way to make casement windows more secure is to ensure that each panel is too small to climb through even if all of the glass is removed, and then to fasten the handle with a lock so that the frame cannot be opened.
If you choose to have casement window frames installed in your home, you have several materials to choose from. Wood has been the most popular material for window frames throughout the history of construction, and the majority of casement frames are wooden. Wood gives you an easy material to work with as you are fitting the windows, and also gives you an aesthetic appearance if it is painted properly. Wood is somewhat prone to warping, which can lead to an ill fitting window where a casement frame is being used.
Although casement windows are not often found made from modern materials, there is no reason why they should not be. It is simply that most of them were built in a previous era when wooden windows were the norm. Vinyl can certainly be used, but that too is prone to a degree of warping. The material which shows most promise is fiberglass, because that will normally stay square and rigid as a frame. It is slightly more expensive to begin with, but it will save money in the long term as it will be longer before you need to replace your casement windows.