Both are inward- and outward-opening alternatives to the double-hung. But a tilt-turn window does something a casement cannot, and the difference shows up in air-tightness, ventilation, and egress.
A tilt-turn window has one handle and two functions. Turn it one way and the sash swings inward like a door. Turn it the other and the top tilts in for secure, draft-free ventilation. The mechanism pulls the sash tight against a continuous gasket on all four sides — which is why these units reach air-infiltration numbers a hinged casement struggles to match.
Air-tightness
Because the locking is multi-point and compresses the whole perimeter, a well-built tilt-turn seals far better than a single- or two-point casement. That translates directly into lower air infiltration — roughly 10% of the maximum allowed under the IECC in our systems — and into comfort, because air-tightness is most of what makes a room feel warm at the glass.
Ventilation and egress
The tilt position gives you secure overnight ventilation that a fully open casement can’t, since the opening is small and at the top. The turn position gives a full, unobstructed clear opening — useful where egress dimensions matter. One unit covers both cases.
Where casement still fits
Out-swing casements have their place — coastal screened porches, or elevations where an inward-opening sash conflicts with interior furnishings. We build both, and the right answer is project-specific. The point is to choose deliberately rather than defaulting to the operation everyone already knows.