Written below are the steps for measuring each dimension of your entry way.

      Dimension #1 On the exterior, Measure in width the dimension from the inside to the other inside of the brick or vinyl.

      Dimension #2 On the exterior measure from the top of the stone sill to the underside of the brick or vinyl at the top.

      Dimension #3 Option #1 Open the door and measure the depth of the existing jamb only (do not include exterior or interior trim). Common       Dimensions are as follows: 4 9/16", 5 1/4" and 6 9/16".

                               Option #2 If you have a door and sidelight unit you must take this dimension at the wall side of the sidelight. Measure from the       furthest exterior point of the jamb to the face of the sidelight than add 1 3/4" for the sidelight. After that you must check on the interior side and       if the sidelight is flush with the jamb you are done. If there is a stop holding in the sidelight you have to measure that depth and add to the other       dimension to get the complete jambs depth.