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Glossary of Terms

Glossary of Common Terms in Consrtuction


Professional Builders tend to use a lot of “jargon” and other words to describe things in their business that most of us will have no idea what they mean. So to “de-mystify” the secret language here is a short translation or glossary of common building terminology.

  • Window Lights (lites) – can often mean a glazed section of the window that opens (top lite / side lite)
  • Window Cill (sill) – the bottom section or “shelf” of a window (inside or outside)
  • Leaded Lights (lites) – window panes that have decorative lead patterns
  • Georgian (Astrical) Bars – the bars that divide a large window into smaller panes
  • Window Head – the top of a window frame
  • Window or Door reveals – the inner recessed wall that surrounds the window or door
  • (Door) Jamb – the vertical sides of the window or door frame
  • Profile – refers to the cross section design of a frame
  • Left or Right Handing – for double doors its which one opens first
  • Lead (pronounced Leed) Door – the main opening door
  • Furniture – handles, locks, letter boxes, hinges etc.
  • Sash – the vertical moving window section
  • Brush Seals – weather proofing strips fitted to window & door frames
  • uPVC – the abbreviation for Unplasticised Poly Vinyl Chloride
  • Engineered Wood – wood made from laminated sections of timber glued together to form a new piece
  • Bumping, Snapping & Drilling – methods used by burglars to break door & window locks
  • WER Label – Window Energy Rating for energy efficiency, shows how good the whole installation is at keeping in heat (A+ is best).

  • Veneer – a thin surface layer overlaid onto the core material of a door
  • Composite Door – one constructed from a combination of GRP Wood & uPVC
  • GRP – Fiberglass or Glass reinforced plastic
  • Low-e or Low emissivity – energy efficient glass that is coated (with a metal oxide)
  • Air Gap – refers usually to the space between the panes of glass in a double or triple glazed window. Can be filled with an inert gas such as Argon to enhance energy efficiency
  • Trickle Vent – a small air ventilation gap that help prevent condensation fitted to double glazed windows.
  • Laminated Glass – a “sandwich” of glass/plastic/glass which makes it harder to break & safer when it does break
  • Solar Gain – usually mentioned when describing the ability of double glazed windows to let in more heat than they let out.
  • Beads (window or door) – strips that fit around a window or door panel to hold the panel (or glass pane) into place. Interior beading is preferred to prevent removal by burglars.
  • Standard door – 2’ 6” wide x 6’ 6” high (1981mm x 762mm)
  • Non Standard Door – typically 2’ 9” inches wide
  • NFR – Non “fire rated” door
  • FD – safety door that is Fire Rated and can last longer in a fire (FD60 = 60 minutes of protection)
  • Impossible – can be done, but at a suitable extra cost. Usually spoken by a builder when faced with changing some aspect of your project.

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Glossary of Terms