A casement window opens outward on side hinges — the full sash swings clear of the frame, like a door. It's the choice when ventilation matters more than space-saving: bedrooms wanting maximum airflow, study rooms that get stuffy, rooms with a wall that has clear space outside. Glassterr manufactures uPVC casement windows at our Pannimadai factory with multi-point locking hardware, gasket sealing all round, and your choice of glazing. Unlike sliding windows, casements seal extremely well when shut because the sash presses onto a continuous gasket — which makes them particularly good for rooms where road noise or rain are concerns.
A uPVC casement window is a single side-hung sash (or a pair side by side) that opens outward, operated by a lever handle that drives a multi-point locking strip. When shut, the sash presses onto a gasket running around the entire frame, creating a tight seal — significantly tighter than a sliding window which seals only at the interlock between sashes. The hinge is a 'friction hinge' that holds the sash at any opening angle without flapping. Casements suit single openings up to about 1.8m wide; beyond that the sash gets heavy and operating becomes awkward. Multiple sashes side-by-side handle wider openings.
Casement when airflow matters most (bedrooms, study rooms) or when sealing matters most (noisy roads). Sliding when swing space is tight (balconies, corridors, kitchens) or when you have a very wide opening. Many homes use both — casement on the quiet/airflow sides, sliding on the balcony side.
It needs clear space outside the opening — typically 60-70 cm clear at maximum sash size. On a balcony with railings close to the wall, casement is wrong. On a normal exterior wall with garden, footpath, or air gap outside, it's fine.
When you turn the lever handle to 'locked', a metal strip inside the sash drives locking pins into three or four points around the frame — top, bottom, and the side away from the hinges. This pulls the sash evenly onto the gasket and resists prying. Single-point latches (like older windows) can be forced; multi-point is significantly more secure.
Yes — the mesh is fixed to the inside of the frame on a removable clip system, since the sash opens outward. You can pop the mesh off for cleaning. Mesh doesn't interfere with the operation of the casement.
Roughly 15-25% more per square foot because of the heavier hardware (multi-point lock, friction hinges) and continuous gasket. For a 4ft × 4ft window, typically ₹18,000-30,000 depending on glazing and hardware grade.
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