Glass block windows are considered as an ideal alternative for traditional pane windows. They are best suited for basement and first floor windows since they provide that extra security to thieves as compared to any normal window.
Although breaking through a glass block windows is possible with the use of a sledgehammer, it is quite impossible for a thief to actually attempt to do it.

Glass block windows appear solid, but those used in residential purposes are hollow. This type of window improves insulation level since slight vacuum is produced inside. This happens once the two halves of the glass block which are fused together by means of pressure and heat cools down. Glass block windows are capable of doubling the insulation value a single pane window provides.

Furthermore, glass block windows are ideal in terms of energy savings. This is because of the fact that glass block windows are capable of reducing air infiltration since they are as airtight like an actual wall. There are also solid glass blocks of commercial quality which available in the market. These types of glass blocks are meant for high security purposes however they are expensive and its weight is considerably heavy.

While there are plastic block halves available, they are not as effective as actual glass block halves in terms of energy efficiency. Plastic block halves are not fused with heat since they are made from acrylic. The most efficient ones in terms of energy savings are those which contain a thin layer of metal atoms on the inner surface. This feature allows them to have an efficient low-emissive property which is responsible in year round energy savings.

Glass block windows can provide natural ventilation similar to any traditional window. This is because like any typical window, they can be opened through various ways or options. One option is by replacing several blocks with a small hopper-style window which can be opened. This does not lessen the security purpose of glass block windows since the opening is actually too small for a person to crawl through. In addition to that, the clear panel is in fact made of polycarbonate bulletproof glass.