How do French casement windows prevent water leakage during heavy rainstorms?

Effective water management is achieved in aluminum French casement windows through coordinated frame design, sealing and installation. Profiles incorporate multi-lipped EPDM gaskets and compressive seals that block direct water ingress. Integrated drainage channels collect infiltrating water and direct it out through weep holes positioned away from the interior, a practice standard in projects from Lebanon to Dubai. Sloped sills, proper flashings and sill pans prevent ponding and encourage outward drainage. For heavy rain events, as occasionally seen in coastal Middle East cities, tested water-tightness ratings and appropriate wind-driven rain resistance levels should be specified. Attention to installation—continuous sealant applied at the perimeter, correct fixing to substrate, and alignment to prevent twist—ensures the window assembly performs as tested. Regular maintenance to clear debris from drainage paths after sand or leaf buildup is recommended to maintain long-term weather performance.