Louvers should be installed with galvanized fasteners andurethane adhesive. Most commonly the louvers are securedthrough the brick moulding. The urethane adhesive shouldbe applied in a 1/4 bead about 3/8″ from the outside edge of the louver and squeezed out to the edge and act as acaulk and sealant to prevent water seepage when the louver is secured with fasteners.
All open louvers may allow water seepage during severe weather conditions. Melton Classics recommends installing a flash pan to catch any water seepage. This can be fashioned out of sheet metal or coil stock and fastened in position before louver installation.