Folding glass walls can be full height from the floor or in large size continuous window openings Photo courtesy of NanaWall, Inc.

Folding Glass Panels
Folding panels can enclose a variety of shapes such as straight walls, open corners, window and door combinations, and even segmented curves. The folding glass wall consists of a number of hinged panels that fold together and slide out of the way. These panels may be hinged together in pairs or in a large number of connected panels like a train. The image below shows a few samples of how the doors could operate. Many opening configurations are possible with inward, outward or center-pivot opening options along with segmented curves and open corners. The swing door is a locking swing panel for easy entry egress within the wall. It is also possible to use this type with a corner-less folding system with paired panels. A special astragal is used to provide a weather tight seal at the corner. More common features of this operable glass wall type are below.

• Mounting: Folding doors can be top hung or floor mounted. The standard system is top hung, where the main weight is carried by the head track and the bottom track is a guide. The floor mounted system is recommended for applications where the load bearing capability of the header is a concern and in this case the main weight is carried by the floor track.

Folding glass panels can be configured to stack in different patterns between left and right side stacking patterns. Image courtesy of NanaWall, Inc.

• Panel sizes: Generally, panel heights of up to 9’-0” and panel widths of up to 3’-3” can be framed in solid wood, aluminum clad over wood, or all aluminum, thermally broken or not. The frame material will affect the maximum width and maximum height, so verify heights and widths with the manufacturer. In height, aluminum folding panels are typically available up to 12’-0”. The openings can range from as few as two panels to as many as twelve panels, and with additional paired panels, virtually unlimited widths are possible.

Folding panels can be configured to suit a corner free installation with a specially designed astragal to maintain performance. Photo courtesy of NanaWall, Inc.

• Frame materials: Aluminum frames are available in a large number of finishes and colors. Standard wood choices generally include douglas fir, pine, and some hardwoods but many other wood choices are available, including FSC certified wood and bamboo laminates.

• Glazing: Glazing options include clear insulated, insulated low-E, triple insulated low-E, bird protection glass, turtle glass, heat mirror, impact and other specialty glass.

It is important to note that folding doors are always stacked perpendicular to the opening. The amount of space that the folding doors will take away from the opening is dependent on the number of panels, panel width, height and thickness. There are a multitude of configuration options, paired panels allow for the best flexibility in configuration. We have already mentioned that folding panels can be thermally insulated with possible U values as low as .17 and water penetration test results of 12 psf. Also a non- conducting thermal break in aluminum systems eliminates condensation.