10.030.0433 Sill and mullion rebuild | Terra cotta, extruded
This detail illustrates a modern rebuild strategy for replacing existing architectural terra cotta (TC) sill, mullion, and accessory units around window openings. The existing TC is replaced with new extruded TC units, installed not filled, with weep holes at the underside of each overhanging unit; each secured with new stainless-steel anchorage. In restoring and rebuilding these types of historic wall systems, moisture mitigation is critical to their long-term preservation and performance. Moisture management measures in this detail include horizontal skyward-facing joint treatment of sealant or lead T-caps, and an integrated flashing system beneath the sill. The flashing system includes a self-adhering flashing with ends dams secured by a termination bar with continuous sealant, a stainless-steel drip edge, and weeps in the vertical joints. The existing structural steel supports are also protected by cleaning and coating with a corrosion-inhibiting coating. These TC rebuild details