Front Door Jargon Buster

Jargon buster

To find the explanation for your jargon term just browse the terms below.


  • Composite Door

    Also known as: Comp Door

    A composite is something made up from several elements and this is also true of a Composite Door - it is made up of a timber sub-frame which is filled with high density foam. The surface of the door is coated with GRP for a durable yet beautiful appearance. 

  • Furniture

    Also known as: Hardware

    Furniture is the term given to the handles, letterbox and door knockers on a front/composite door. They are the final items that finish off and decorate the door, just as furniture finishes off and decorates a room. 

  • Drip Bar

    Also known as: Rain Deflectors

    The Drip Bar sits at the bottom of the door on the external face and is there to deflect any rain running down the surface of the door away from the home. 

  • Sub-Frame

    Also known as: Sub-Frame

    The Sub Frame is essentially the skeleton of a Bowater Composite Front Door - giving the door a structure around which the other components are built. 

  • Low-Profile Threshold

    Also known as: Low-Profile Threshold

    A Low-Profile Threshold is a lower alternative to the standard threshold - the benefit is that a low profile threshold is less of a trip hazard. 

  • Backing Glass

    Also known as: Backing Glass

    Backing glass is the clear or obscure glass which sits behind the patterned glass chosen to personalise your Bowater Composite Door. 

  • Patterned Glass

    Also known as: Patterned Glass

    The Patterned Glass is used to personalise all the Bowater Composite Doors which can be glazed. Patterns are available in a range of traditional and contemporary styles.  

  • Triple Glazed

    Also known as: Triple Glazed

    Some of the glazing options for Bowater Composite Doors are Triple Glazed, which means there are 3 panes of glass instead of the stand 2 panes. This offers further enhanced thermal efficiency. 

  • Cill

    Also known as: Cill

    The Cill protrudes beyond the frame at floor level on the outside of the door and serves a similar purpose to a window cill - it finishes everything off neatly and also directs any rainwater away from the home. 

  • Spyhole

    Also known as: Door Viewer

    The Spyhole is a small viewing hole which is an optional extra on the door knockers on Bowater Composite Doors - it allows you to see who is stood outside before opening your front door. 

  • Door Sash

    Also known as: Sash

    The Door Sash is the actual door area which opens out from the frame. 

  • Side Panels

    Also known as: Side Lights

    Side Panels are the vertical panels of glass and/or composite door material that can be used on one or both sides of a composite door. Side Panels give the front door a more decorative home and allow extra light into the hallway of your home.  

  • Threshold

    Also known as: Threshold

    The threshold is the area at the bottom of the door frame which you step over the get into the house. 

  • U Value

    Also known as: U Value

    The U Value is the term used to describe the energy efficiency of the door and the lower the number the better the thermal performance. Current Building Regulations demand a minimum U Value of 1.8 for doors - all Bowater Composite Doors have a U Value of 1.6 or less, with some boasting an incredibly low U Value of 1.0. 

  • Edgeband

    Also known as: Edgeband

    The edgeband is the strip which runs vertically down the side edge of the door - providing a neat, clean finish. Edgebands on Bowater composite doors feature a grained effect to match the door surface and are white on coloured doors and woodgrain on Golden Oak and Rosewood doors. 

  • Frame

    Also known as: Door Frame

    The Frame is the area around the edge of the door which it closes into. Bowater Composite Doors come with a choice of frame colours - Woodgrain doors have matching frames in either Golden Oak or Rosewood, whilst coloured doors are supplied with a choice of white or black frames.  

  • Woodgrains

    Also known as: Golden Oak, Rosewood, Foils

    Woodgrain is the name for the finish on the Composite Doors which look like wood (IE not colours such as red). Bowater Composite Doors are available in 2 Woodgrain finishes - Golden Oak and Rosewood. 

  • GRP

    Also known as: Glass Reinforced Polymer

    The external surface of a Bowater Composite Door panel is made from GRP (Glass Reinforced Polymer). GRP is a highly durable material that is much more hard wearing than a traditional painted timber door which means that time consuming "touch-ups" are required much less frequently – if at all. 



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