Glossary

UPVC- Unplasticised Polyvinyl Chloride.

Frame- The part of the window fixed to the masonry work (Chowkhat, चोखट ).

Sash- Openable part of the window/door (Palla, पल्ला).

Casement Window/door- Windows with swinging open-able panels (sashes).

Sliding Window/door- Windows/doors with sliding open-able panels (sashes) window/door.

Transom- Horizontal dividers of a window/door outer frame.

Mullion- Vertical dividers of a window/door outer frame.

Mid rail- Dividers (horizontal or vertical) in a window/door sash.

Bay window- A combination of at least three windows that projects outward from the main walls forming a bay in a room, either square or polygonal.

Tilt & Turn Window- A window that (i) tilts at an angle  for ventilation and (ii) opens inwards like a casement.

French Window-  Combination of two casement window with 100% opening.

Multi point locking- A locking mechanism that locks at more than one point.

Double Glazed Glass-  Multiple layered glass panes that have very dry air or inert gas between the glass panes. [Double Glazed Glass can be called Insulated Glass Unit (I.G.U.) or, Double Pane Glass or, Double Glazed Unit (D.G.U.)].

                                                       Double Glazed Glass

Deflection in a Window/Door - Wind speed load on the window/door will result in the deflection of the unsupported Transom = f (Check below mentioned picture).

Tensile Strength- It is the maximum stress that a material can withstand while being stretched or pulled, which is when the specimen’s cross-section starts to significantly contract. Tensile strength is the opposite of compressive strength and the values can be quite different.

U-Value-  Level of Indirect sun heat loss. Lower it is, higher the level of thermal insulation.

U-value calculation for windows-In windows there are always three different U-values:

• U_w (w = window) – overall value of the window
• U_g (g = glazing) - U-value of the glazing
• U_f (f = frame) – U-value of the frame

The heat transfer coefficient U_w relates to the entire window. This value also incorporates the U-values for the glazing and the frame U_f. The overall value Uw is also influenced by the linear heat transfer coefficient (g = glazing) and the size of the window.

Low-E Glass- Introduced in 1979, Low E glass works in a way in which reflecting heat back to its source. It is basically for controlling thermal insulation. If we see electro- magnetic spectrum of sunlight, it comprises visible light, Infrared(heat) & UV light. Low-E glass has the ability to transfer visible light but blocks IR rays as well as UV rays upto certain level. To understand more about Long & Short Infrared rays, UV , Please check below pics.

Electromagnetic spectrum of Sun

Electromagnetic spectrum of Sun

Electromagnetic spectrum of Sun