October 26, 2017

M – P

M – P



Masonry opening
The opening left in a masonry wall to receive a window or door unit.

Meeting Rails
Horizontal Intermediate sash members that meet when the window is closed such that they combine to act in unison.

Meeting Stiles
Vertical intermediate sash members that meet when the window is closed such that they combine to act in unison.

Vertical framing member between window units.


Nailing Fin
An integral extension of a window or patio door frame which generally laps over the conventional stud construction and through which nails are driven to secure the frame in place.

National Fenestration Rating Council.


Obscure glass
Any textured glass (frosted, etched, fluted, ground, etc) used for privacy, light diffusion or decorative effects.

Operable Window
A window that can be opened for ventilation.


Framed sheet of glass.

Panel Wall
A non-load-bearing window wall that is wholly supported at each storey.

Pascal (Pa)
The pressure or stress that arises when a force of one newton is applied uniformly over an area of one square metre.

Permanent Vent
A part of the window that provides ventilation even when the sash is in the closed position.

Picture Window
A large, fixed window framed so that it is usually, but not always, longer horizontally than vertically to provide a panoramic view.

Pivot Sash
Window units in which the sash hardware is located near the midpoint of the stile or rail to permit sash rotation.

Plastic Film
A thin plastic substrate, sometimes used as the inner layers in a triple or quadruple glazed window.

Prepared Opening
An opening in a building made prior to the installation of the window.

The plastic interlayer incorporated into laminated glass in order to ensure good adhesion and the mechanical and safety breakage characteristic of the glass.

‘Poly Vinyl Chloride’ is a material used for flexible (or rigid) glazing gaskets and weather seals. Flexibles are soft and can take up variations in tolerances within the window.