What’s the Best Way to Seal Aluminum Windows in Facades?

Effective sealing combines high-performance sealants, precision extrusion tolerances, and robust gaskets. Use neutral-cure silicone sealants rated to ASTM C920, Class 25, ensuring elasticity and adhesion to anodized or PVDF-coated aluminum. For joints between window frame and metal panel, design a backer rod–sealant assembly with a 2-point seal: a primary silicone bead on the exterior face and a secondary silicone bead behind the backer rod. Closed-cell EPDM gaskets sit within continuous grooves on the window flange, compressing against the panel to form a pre-seal before silicone application. Flashing tape—self-adhesive, high-temperature resistant—applies around the rough opening to integrate the window into the air and vapor barrier behind the facade. Above windows, integrate drip edge flashings and panel joint diverter trims to channel water away. For ceiling perimeters adjoining the window head, specify structural silicone glazing jambs that eliminate metal trim, using the same sealant for consistency. Regular inspection and re-seal every 10–15 years extend longevity, keeping your aluminum window and facade system watertight without intrusive maintenance.