Flush-casement windows are a type of window design where the window sashes (the frame holding the glass) fit flush, or level with the surrounding window frame when closed. This design creates a clean, streamlined look, as the window sash does not protrude outward or inward from the frame.

Here are some key features of flush-casement windows:

  1. Design: The window sash is hinged on the side (typically) and opens outward. When closed, it aligns evenly with the frame, giving it a smooth, integrated appearance.
  2. Aesthetics: The flush fitting gives a modern, minimalist look. It also allows the window to sit neatly against the wall, without the bulky appearance of some other window types, such as traditional casement windows where the sash might be visible or protruding.
  3. Materials: Flush-casement windows can be made from various materials, such as wood, aluminum, or uPVC (plastic). The material used can affect the durability, insulation, and appearance of the window.
  4. Energy Efficiency: These windows often provide better insulation compared to traditional windows, as the sash is designed to fit tightly within the frame, reducing drafts and improving thermal performance.
  5. Security: The flush design can enhance security, as there are fewer external elements (such as projecting parts) that could be tampered with.

In terms of function, flush-casement windows are often favored for their clean aesthetic and modern feel, as well as their efficient insulation properties.