How Are Plexiglass Windows for Homes Constructed?

Plexiglas® is a trademarked product owned by the chemical company Rohm and Haas. Its scientific name is polymethyl methacrylate or PMMA for short, and it is a clear, colorless polymer that is a perfect shatterproof replacement for glass and other optical applications.

Why use Plexiglas® in Windows?

Compared to glass, Plexiglas® weathers better and is more scratch resistant. Its toughness makes it an ideal replacement for window glass where otherwise it would be shattered by flying objects, severe weather or vandalism. Unlike glass, which is difficult to see through as it becomes thicker, Plexiglas® retains it's transparency up to 13 inches of thickness.

Plexiglas® Panes

Manufacturers who build Plexiglas® windows use a variety of different thicknesses of the acrylic, depending on customer specifications. Since Plexiglas® is stronger than regular window glass, there is no advantage in using thicker panes to prevent breakage. Energy efficiency will also not be increased with thicker panes since that is gained through the use of the dead air space between the separate panes.

Window Frame Construction

Modern window manufacturers use a variety of different materials to build window frames. They utilize wood, vinyl, aluminum, fiberglass or composite materials. Each of them has its advantages as well as its disadvantages. Wood and composite materials frames, for instance, are the easiest to paint. Vinyl, composite materials and fiberglass frames are the most energy efficient and aluminum, vinyl, composite materials and fiberglass frames are the most maintenance free. Conversely, wood frames require the most maintenance. Aluminum frames are the most energy inefficient and vinyl and aluminum frames cannot be stained or painted.

Regardless of their make-up, window frame corners are generally constructed with 45-degree angles instead of with butt joints for added strength and for aesthetics. Grooves are cut with a router inside the frame where the Plexiglas® panes will be seated. Depending on whether the window will be of a single-pane, double-pane or of the most energy-efficient triple-pane construction, the number of grooves that are cut in the frame will be equal the number of panes that are to be installed.

Final Construction

The individual Plexiglas® panes are pressed into their respective frame grooves with glazing compound. Glazing points are installed on all sides of the window pane until the panes are firmly seated. Finally, the finished product is inspected for manufacturing defects and is then packaged for delivery to distributors and customers.

References

PolymerProcessing.com
http://www.polymerprocessing.com/polyesters/PMMA.html

Polymer Science Learning Center, The University of Southern Mississippi
http://pslc.ws/macrog/kidsmac/pmma.htm

Acrylics USA, LLC
http://www.acrylicsusa.us/size_thickness.html

UBuildIT.com
http://ubuildit.com/blog/building-products/windows-skylights-sunrooms/what-are-my-windows-made-of/

How to Make Plexiglas® Windows
http://www.mightyguide.net/how-to-make-plexiglass-windows.html

MyPlaticstore.com
http://distributionbizwiz.wordpress.com/2007/09/13/diy-acrylic-storm-windows/