The organ is housed in casework according to the classical Werkprinzip designed by Gabriel Kney and Art Seager. The wood used is Pennsylvania red oak stained to match the other woodwork in the chapel. In the main case, the lowest division (under expression) is the Swell, with the Great in the middle and the Oberwerk on top. The large pipes of the Pedal division are in a separate case behind the main case. The basswood pipe shades and grille over the Swell shutters were carved by Gabriel Kney based on motifs found in the paintings on the ceiling of the chapel.
The key action is mechanical. The stop action is electric, by drawknobs in terraces on either side of the keyboards. The manuals use ebony wood for the naturals, and coral padauk with white bone overlay for the sharps. The original combination action was solid-state capture type with eight memory levels. In 2008 the combination action was upgraded to a 256-level capture system. The chests employ a pallet and slider system. The winding is supplied by seven wedge-shaped bellows, allowing different and stable wind pressure to the various divisions.
The tonal design and scaling of pipes were done by Gabriel Kney. The wooden pipes of white pine or mahogany were made in his shop. The metal pipes, custom-made by independent pipemakers, vary from 80% tin for pipes of principal character to 40% tin for those of flute character. The horizontal trumpets are burned copper.
The attached console has an enclosed television monitor on the right which permits the organist to see the choir conductor, the sanctuary, and to coordinate antiphonal performance from the gallery. On the left, also enclosed, is a telephone.