It means the door is 30 inches wide.
The standard dimensions for a 30" door are 30 inches in width and 80 inches in height. To ensure it fits properly in your doorway, measure the width and height of the doorway opening accurately before purchasing the door. Make sure the door frame is square and level, and adjust as needed to accommodate the door.
The rough opening required for a 30-inch door is typically 32 inches in width and 82 inches in height.
There is not a quote "standard" door width as doors can be purchased in 2" increments. There are a few building code restrictions for minimum width of certain doors. Like an egress door is required to be 36 inches in width for a residence. There can also be minimum widths for handicap accessibility. These doors in a house need to have a clear opening width of 30 inches.
Given an inch is 2.54 centimeters a 30 inch door (or anything else 30 inches long) will be 30x2.54 centimeters long
The recommended rough opening size for a 30-inch door is 32 inches in width and 82 inches in height.
There is actually no actual measurment you will have to measure it for yourself to fin out
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The recommended rough opening size for a 30-inch interior door is 32 inches in width and 82 inches in height.
The standard rough opening size required for a 30-inch door is 32 inches in width and 82 inches in height.
width of car door
The dimensions of an average American front door is 36 inches wide and 80 inches high (3' x 6'-8").
The most often chosen width of a front door is 36".