Sunday, October 26, 2014

Shadow Box Design

From HOLT Architects:

Our typical shadow box detail specifies a composite aluminum panel for the interior closure material.  We have recently run into issues with the panel deforming and expressing waves.  The theory is that this is due to the interior plastic core of the panel melting.  Allucobond is rated to 170-180 degrees, but due to the dark color that was selected for this project it may have been possible.

In the future, when we design and specify shadowboxes we should simply use a 1/8” aluminum panel with a Kynar finish rather than the composite metal panel option. (see Breckenridge)

Venting of the space between the glass and the panel is also becoming a common practice.  This can be done in two ways:   1. Removing 1” the interior glazing gasket at both top corners of the glass panel in front of the shadow box will let the air space vent into the glazing pocket.  2. Drilling two ¼” holes at the top of both sides of the vertical mullion within each shadowbox will let the air space vent into the vertical mullion.  We should coordinate the preferred method of venting with the approved window manufacturer.