Measure the horizontal distance from one side of the space to the other. For a more accurate measurement, use a level (or a tape measure with a built-in leveling indicator) to ensure that you are measuring straight across the space. Measuring along the floor can help, but it is not as accurate as using a level tool.
2
Measure vertical clearance
Measure the vertical distance from the bottom of the space to the top. Again, use a level (or a tape measure with a built-in leveling indicator) for accuracy.
