Minimum internal door width
How to Measure a Door? What is standard door width? : Minimum Internal Door Width
Quote from Article entitled How to Measure a Door? What is standard door width?:
More often than not, the measurements are taken at the very top edge, the bottom edge and along the middle of the door. This is done to ensure that the door is uniform in width from top to bottom. In order to get the middle point, all you have to do is to measure the door’s length at any point and mark the midpoint using your chalk or pencil.
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