KC EGRESSWINDOWS
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01 / MEASURE YOUR OPENING

Measure what’s open.
Understand what’s next.

Calculate the area of a rectangular, unobstructed opening. Keep the other project checks in view.

Record the clear dimensions

Measure the usable space with the window opened normally. Do not enter the frame size, rough opening or glass dimensions. Read the measurement guide first if you are unsure.

The unobstructed width after opening the window.
The unobstructed height in the same configuration.
A calculation is one part of the review.

Minimum width, minimum height, sill height, well dimensions, access, covers and applicable local requirements must be checked separately. A large area does not automatically mean the window meets them.

Your measured opening

—square feet of rectangular clear opening

Enter both measurements to see the calculation.

This tool does not determine code compliance or permit approval. It does not select a grade-floor exception or compensate for obstructions and irregular shapes.

Still to confirm

  • The exact window and operating hardware
  • Required minimum width and height
  • Finished-floor-to-sill measurement
  • Exterior well and escape access
  • Your jurisdiction’s current requirements

Example: 30 × 28 ÷ 144 = 5.83 ft². That arithmetic alone is not an approval. Check local sources.

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