Aperture

An opening in the structure into which the window or door is to be installed.

Base Coat

Used in a similar fashion as a primer to improve adhesion but with a specific top coat application.

Bay Pole (Bay Post)

An independent structural member or assembly used between individual bay segments, to carry applied loads

Bay Segment

The individual window which forms one facet of a bay window assembly

Bay Window

A multi-faceted window, which forms an integral part of the façade of a building, and which projects no more than 1.5 metres from the building line

Bearing Plate

A plate usually of steel or aluminium, used between the structure and the bay pole to spread the loads from the structure to the bay pole, and vice versa, to prevent damage to the structure

Bevels

Glass ground and polished to an angle for a more decorative effect.  These can be applied as separate stick-ons.

Bow Window

A type of bay window, usually carrying only light loads, which does not form an extension to the floor area of the room.

Coastal Environment

Any dwelling within a radius of 7 miles from a high tide shoreline.

Dormer Windows

A vertical or near-vertical window built into and projecting from a pitch roofed structure

DPC (Damp Proof Course)

A device, usually comprising a layer or strip of material placed within a wall, chimney or similar construction prior to prevent the passage of moisture

Drainage Slots

Part of a window drainage system.  Used to carry water away from the bottom edge of an insulating glass unit

Frame

Surround to a door leaf, window, etc enabling it to be fixed into position

Friction Stays

Hinges fitted either side of an opening window to enable it to be opened and to retain its position

Gaskets

Performed glazing seals made from rubber or soft plastic material

Glazing Beads

A section/profile which retains the glazing in position

Hardware

General name for window and door fitments such as handles, locks, letter boxes etc, (sometimes called 'furniture')

Head Plate

A structural member forming part of the fabric of the building at the head of a bay window assembly, spanning between bay poles and/or between bay poles and the building

Industrial Environment

Any dwelling within a radius of 7 miles from an industrial estate or large factory complex

Leaded Glass

Glass which incorporates lead alloy strip to simulate traditional leaded lights

Lintel

A beam supporting loads over an opening

Oriel Window

Multi-sided window projecting from an upper storey and generally supported by brackets

Polyurethane

A polymer having isocyanate links used in the formulation of sealants. An adhesive sealant can be single component (moisture curing) or double component (chemical curing). Also known as Urethane and PU

Primer

A coating used to improve adhesion to the substrate to which it is applied

Safety Glass

Glass that meets the requirements of British Standard BS 6206

Sashes

Opening part of a window frame

Silicone

A basis for the silicone sealants (available in a number of types)

Sill

Projecting member of the window at the base integral within timber/aluminium window frame

Structural Mullion

A load-bearing intermediate vertical member of the building fabric, which transfers applied work load from the structure above an opening to the structure beneath

Structural Opening

An aperture in a wall into which the window or door is to be installed

Structure

The main building elements e.g. walls, roofs and floors

Sub-sill

Swarf

Trim

Decorative architrave fitted to the perimeter to a window

Weatherseals

Compressible strips around any opening window or door perimeter, which prevents wind and rain penetration