Uphill, the guest wing, set on leveled ground, echoes many of the themes introduced in the main house. The bravura of the glass curtain wall of the west tower is matched by a curved, repeatedly stepped (i.e., folded) canopy over the walk. The canopy rises from the rear of the main house and circles around a big oak tree until it meets the upper structure. This bold canopy is supported by steel posts on only one side; on the other, the tension created by a ring beam with additional reinforcing rods prevent the slab from sinking - a true tour de force. The canopy continues straight eastward along the front of the guest wing to form a trellis echoing those below; this trellis includes the longest cantilever of the whole house, very quietly presented.
- Edgar Kaufmann, Jr.,
Fallingwater: A Frank Lloyd Wright Country House, p. 114.