Introduction
A window consists of two main components: frame and sash. The only exception is FIX, which is also a window but without sashes – glazed directly into the frame.
Frame is the main structural element of the window, assembled in the wall (more on how to install in other article). Bottom part of the window frame is called the threshold.
Sash is the movable part of the window attached to the frame by hinges. Depending on the number of sashes, windows can be single- or multi-sash. Multi-sash windows have vertical posts (dividing the window vertically) or transoms (dividing window horizontally – also called “mullions”).
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1. Window frame 2. Window sash 3. Threshold (bottom part of the window) 4.Upper sash quarters 5. Lower sash quarters |
Vertical posts can be fixed (permanently connected to the window frame). When the sashes are opened, the post divides the window frame. There can also be movable posts (attached to one of the sashes) and after opening the window there is no division of the frame. The analogy is with horizontal posts – transoms. A movable transom is called a “horizontal movable post”, but more about it in other article.
As a result of the division of the window by vertical and horizontal posts, spaces called “quarters” are created.
The window frame and sash are made of wooden profiles, which are formed from scantlings (glued in layers wood). The main parameter of the profiles is their depth (thickness), which significantly affects the strength of the window structure and the heat transfer coefficient of the window. Another dimension of window profiles is the width (height).
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df – frame depth, ds – sash depth, wf – frame width, ws – sash width |
For inward opening wooden windows, we offer three thicknesses (depths): 68mm, 78mm, 92mm. The same thicknesses apply to entrance doors and balcony windows/doors. In our offer, the depth parameter determines the name of the entire system (windows, doors, slidings, etc.) and functions under the names: Ecoline-68 (for 68mm depth), Thermoline-78 (for 78mm depth) and Ecotherm-92 (for 92mm depth).
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The bottom part of the window frame, called “threshold”, can have different shapes, depending on customer’s requirements or expectations, or world region where the window is to go.
More about differences and choices in other articles
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