Tom Shafer

19 window terms to know

June 24, 2014

If you're discussing replacing your windows with a window salesperson/expert, it might seem like you're speaking different languages. Industry-insider lingo can seem indecipherable, but with a glossary in hand, you'll be talking like a pro in no time. Below are some more obscure definitions you may be having trouble with:

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  1. Daylight opening - The area of the glass; the opening that allows daylight into the home.
  2. Buck opening - The opening size between the horizontal and vertical frame in the house.
  3. Fin window - A window used in new construction. It has a flange through which to nail, or a nail fin, hence the name.
  4. Commodity size - -Set sizes used in Florida - i.e. 5/2 or 3/5.
  5. Modular sizes - Commonly used sizes in wood frame construction.
  6. Combo unit - Windows comprised of two or three windows; mulled windows.
  7. Mulling - Combining two or more windows into one unit (see above).
  8. Continuous head and sill; one piece head and sill - Piece used when two or more windows are combined in the factory.
  9. Stacked units - Windows with a transom, an arch, pr a half round attached to a window below it.
  10. OX, OXO, XO - Movement pattern of windows. X is the moving panel and O is the fixed panel.
  11. XX - Both sashes move.
  12. Oriel window - A vertically operating window where the lower sash is 1/3 the size of the upper sash.
  13. Cottage window - A vertically operating window where the lower sash is 2/3 the size of the upper sash.
  14. Single strength glass - 3/32" thick glass - or 3mm.
  15. Double strength glass - 1/8" thick glass - 4mm.
  16. Laminated glass - Glass with a layer of .15, .30, .60, or .90mm heavy vinyl laminated in a sandwich between two layers of glass.
  17. Impact glass - Glass for hurricane protective windows, usually laminated with .90mm thick vinyl
  18. Jamb adjustor - A device on the jamb of a replacement window that assists an installer in squaring the window.
  19. Grid patterns:
  • 1/1 - No grids in top sash, none in bottom
  • 2/2 - 2 lites/2 lites
  • 4/4 - 4 lites/4 lites
  • 6/6 - 6 lites/6 lites
  • Prairie - Grids on perimeter or glass about 4" from edge
  • Diamond - Grids in a diamond pattern

Window jargon is confusing. Not understanding these terms might put you into position where you order an incorrect window. If confronted with window and door terms that you do not know, ask to have them explained.

About the Author

Tom Shafer has decades of experience in window sales, marketing and product development. He's worked closely with window design engineers in testing, design, and building code interpretation. Past employers include United Windows and Doors and Norandex, MI Windows. He currently works at a home improvement retailer.


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