A recess or groove cut into the edge of a piece of wood e.g. a window sill. Makes provision for the insertion of a pane of glass and putty or for another piece of wood.
It is also used in door and casement window jambs, e.g. on the edge of the casement, where it overlaps the frame. The natural ‘air’ between frame and casement is hidden.
Round window divided into segments by stone mullions and tracery. The term “rose window” is reserved for those windows of more complex design which can be seen to bear similarity to a multi-petalled rose. May have glass paintings. Often found in church gables. Also called Catherine window.
A window type invented for the Winter Palace in St. Petersburg, Russia. A double-glazed window consisting of two windows built together to a unity. The outer window has an operable sash at the bottom and the inner an operable sash. In addition to a good insulating power the system reduces heat loss during ventilation, because the fresh air is preheated on its way inside. At the same time the system is sound-absorbing.