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How To Measure for Windows and Doors

If you are lucky enough to have the original plans for your home and the windows are original, bring the blueprints when you come to your nearest Dolan’s to shop all the quality name brands. Otherwise, get out your measuring tape, notepad and pencil, and measure the windows and doors you plan to replace. After reading this article, if you have questions about measuring, call your nearest Dolan’s location. When you visit us, you’ll be able to consult with a Dolan’s window and door expert in person. Call 800-936-5267 and select your nearest location to speak with an expert. Here are some tips.

Note: The measurements you take should be as accurate as possible because estimates will be based on these measurements. Before you order any custom windows, your contractor or a Dolan’s expert will measure each and every window and door opening according to your manufacturer’s specifications.

The easiest way is simply to measure the width from sheetrock to sheetrock and measure the height from sheetrock at the top to the bottom sill.

If you are measuring wood sash windows, you want to open the window and measure from jamb face to jamb face. Measure in three places, near the top, the middle and near the bottom in case there is warping. Height is measured from the head jamb down to the highest point of the sloped sill. Again, measure left side, middle and right side. When you provide measurements always give the width first and then the height.

If you are measuring an aluminum window opening, open the window and remove the screen so you can determine which flange is the widest. Then measure from that flange to the same one on the other side of the window. Measure at the top, center and bottom and use the narrowest width. Measure height the same – three places, left, center and right.

Keep in mind that today’s new windows can be joined together to fill almost any opening. Where you have one large window, you may want two narrower windows. Where you have two double hung windows, you may want one large window. So again, the easiest way to measure with would be from sheetrock on the left of the window on the left to sheetrock on the right of the window on the right.

Patio door measurements should be taken from side to side inside the doorframe. Standard two-panel doors are usually 5, 6 or 8 feet wide. Standard height is 79.5 inches.

Entry doors and interior doors are easy, but accuracy is important. Simply measure the width and height of the door and don’t forget to measure the depth or thickness of the door. If you have sidelights, measure the width and height of each sidelight only.

Suggestion: Bring picturesto Dolan's of the interior and exterior of your entry door, sidelights if any included. If you plan to purchase a pre-hung unit, measure the door, and sidelights if any, including the frame. Keep in mind that Dolan’s has a professional door shop and can trim to fit for a nominal price.

Helpful Window & Door Terms:

  • Casement Window – window unit with a single sash that cranks out either to the left or to the right.
  • Casing – molding of various widths, thickness and shapes that goes on the framework of windows and doors.
  • Check rail – on a double-hung window this is where the lock is mounted connecting the bottom rail of the upper sash and the upper rail of the lower sash.
  • Cladding – material that is married to the outside facing of doors and windows providing a protective,  low-maintenance surface.
  • Cottage double-hung window – the upper sash is shorter than the lower sash.
  • Double-hung window – the window has two operating sashes that move up and down within the frame.
  • Fixed window – a non-ventilating or non-operating window.
  • Flashing – a strip of material that diverts water away from a window, roof window or skylight.
  • Frame – the enclosure to which window sash or door panels are mounted.
  • French hinged door – hinged door or doors with wider panels around the glass.
  • French sliding or gliding door – has wider panels around the glass resembling a French hinged door.
  • Grilles or grids – windowpane dividers, permanent or detachable, to give the “divided light” look.
  • Head – the main horizontal piece that forms the top of the window or doorframe.
  • Header – the main framing piece that prevents the wall from resting on the window frame.
  • Jambs – the vertical pieces that form the sides of a window or doorframe.
  • Jamb liner – the sliding track installed inside the jambs.
  • Rail – the horizontal pieces of the framework of the window sash.
  • Sash – the pieces that form the frame that holds the glass.
  • Sidelights – fixed glass units on either side of doors that give a wider appearance.
  • Sill – the main horizontal piece that forms the bottom of a window or doorframe.
  • Single-hung window – the top sash is fixed and only the bottom sash moves up and down.