Measuring for the vertical four track inside mount Eze-Breeze Vinyl Window unit.
When ordering the Ez-Breeze vertical four track units, and most other Ez-Breeze units, we prefer to work with the smallest daylight opening. Always give width first and then height.
It is necessary to have a one inch mounting surface in the corners to attach the mounting flange of the window. In other forms of construction this might be called a nailer. It is common to add a 1x2 in the corners of some rooms, giving both windows a mounting surface.
Be sure to measure in at least three places for each width and height. Use the smaller of the three measures. Typically, say for the width, you would measure across the top, center and bottom.
When manufactured, the part of the unit that fits into the opening will be approximately 3/8" smaller than the opening size given to us. This is to allow for out of square conditions.
The windows are packaged with very good instructions, follow them and your installation will go smoothly, provided you measured correctly.