For most people, it comes as a surprise when they discover just how wide a variety of windows there are to choose from today. A broad selection of windows made from wood, metals and new high-tech durable plastics that come with amazingly lengthy service lives. So many different window types that not only look different but that also function differently, so they’re capable of fulfilling a variety of functional, structural and architectural requirements. So given the number of options there are to sort through, it’s just a good idea to become familiar with at least the more commonly used of them before you start in with your remodeling or new construction project.

A multi-pane window, also commonly referred to as a thermal window contains more than one pane of glass layered over one another with a hollow pocket separating them. They function to prevent the high loss of thermal energy that occurs in single pane windows, and in some states in the US they’re now required my standard building code on all new construction. There are two layer and three layer multi-pane windows, and more recent developments are multi-pane windows that contain a less thermal conductive gas such as argon in the air pocket, and clear glass coating that works to block out the heat energy of the sun while letting the light pass through.

A fixed window is quite simply a window that cannot be opened. There’s any number reasons why someone would want to go with this option, including security, increased interior lighting, solar heating, optimal viewing, and the lack of need for a non-fixed window because of air conditioning. Keep in mind though, that building code requires that a bedroom window be non-fixed and large enough for a person to climb out of in an emergency.

A kitchen greenhouse window screws easily onto outer trim and contains multiple windows and racks in a metal framework to form what is essentially a micro-greenhouse. Increased popularity in greenhouse windows has led to the development of more options and reduction in prices, and they remain a good choice for someone looking to add dimension to a kitchen or cover-up a bad view.

A tempered glass window contains especially treated impact resistant glass. It’s not hard to imagine some of the uses for a window with glass that’s more difficult to break than the standard pane but in some instances it’s required by standard building code. Glass doors for instance are required to be made from tempered glass and also windows in homes that are installed low on a wall are also required to contain it to prevent small children from falling through.

A single hung sash window is a sash window that only allows for one of the pair, usually the lower to be opened. Sash Windows have always been popular, and will continue to be so, and a single hung sash window is the cheaper of the two options when choosing between single hung and double hung.

A double hung sash window is a model that allows for either window; top or bottom to be opened up. This type of window will cost more than a single hung sash but it provides for greater top end ventilation if there is the need, easier access for cleaning and it also allows for the option of opening an upper window, out of reach of small children.

A horizontal sliding sash window is a sash window that’s installed in a home laterally rather than vertically, so they open from side to side. Two reasons why someone might choose the horizontal sliding sash window are that they can be mounted higher on a wall to keep them out of reach of children, and architectural restrictions where a standard upright sash window wouldn’t fit.

A casement window can come in a few different configurations, ranging from one single framed in pane, to multiple windows fitted together in a framework. They all have one thing in common though, and that is that a casement window swings out like a door when it is open.

A storm window is a secondary window that’s installed on the outside of an existing frame to provide light protection in the event of a storm, or if the inside window is opened in clear weather. They’re generally aluminum framed in, and function to block out in leaves, debris and whatever else can come in when a window is open. They also provide protection from wind and blowing objects when a window is closed.

An awning window functions just like a casement window; only instead of swinging out like a door when it opens up an awning window is hinged on top and swings out from the top. So it opens up to function like an awning, and this is where it gets its name.

A hopper window also functions in a similar fashion as a casement window. However, in this case unlike the casement window that swings out like a door, a hopper window is hinged at the bottom, so it is opens at the top end swings out. This is where it gets its name from because it looks like a hopper when it’s open.

A jalousie window is sometimes referred to as a louvered window because it’s made up of multiple slats of glass that are arranged in a lateral overlapping fashion. They operate by turning crank that causes the slats to all simultaneously tilt up from the bottom when it is open. They are still popular in tropical regions where they function to deflect rain when open.

A Diocletian window is a half-round window with three separate panes of glass in it, with the middle pane being slightly larger than the other two side panes. More often than not you’ll find them positioned over a double wide doorway where they span from side to side.

A clerestory window refers to the positioning of a window rather than a specific type. This is because this type of window is positioned high on a wall in a building to allow light into the higher reaches of a tall room during daylight hours.

A tilt and turn window is designed to function in two ways. First it can open outwards from the top in the same fashion as a hopper window. Then it will also have a set of hinges which when engaged will allow it to swing outwards in the same way that a door would.

A tilt and slide window operates in a similar dual function fashion as the tilt and turn. In this case though, rather than tilting and opening out, it can tilt and also slide either up or sideways like a horizontal sliding sash window can depending on the type.

A transom window refers to any type of window that is positioned directly above a door. The advent of air conditioning has detracted from their popularity but they still can be seen quite often in less developed tropical regions.