Window Wall 

Challenge: A gable end window wall 26’-9-1/2” x 20’-1/16” with no intermediate structural framing members in the clear opening (see drawing).  The design criteria of minimal horizontal and vertical divisions of 3” or less on approximately three foot centers.  The units that make up the opening have to be handled and installed without a crane.

Solution: The opening is broken up into five vertical units of varying heights.  The intermediate vertical mullions at the field mull locations consist of two pieces of ½” x 5” or ½” x 6” plate steel with wood clad interior and copper clad exterior for an assembled mullion width of 2-1/2”.  These jamb sections are joined with machine screws as the units are set into sequence (see drawing, detail 6).  If you look closely on the photo you can see the field applied copper caps on the vertical field mulls run continuous, all other copper was applied at the factory.  The remaining vertical and horizontal mullions are 2-1/2” wood sections (see drawings, details 2 & 7).

Anchoring of the units to the rough framing at the head and sill is accomplished with steel plates welded to the ends of the flat steel jamb sections at the head and sill (see drawings, details 4 & 6).

To facilitate handling without a crane, the units were glazed on site.  This allowed the contractor to handle units weighing a few hundred pounds each, rather than units weighing over one thousand pounds each.

Products Used:

  • Direct set window wall

End Result: The window wall is the focal point of the house and the architectural design intent was not compromised.


Project ID: P5-A100