Door Size Calculator
Door Rough Opening
Calculate the rough opening needed for a door
Door Swing Clearance
Calculate the floor clearance area needed for a swinging door
Formula
Rough Opening Width = Door Width + 2" | Rough Opening Height = Door Height + 2.5" | Swing Area = 0.5 × r² × θ
Frequently Asked Questions
What is a standard interior door size?
The most common interior door size is 32" or 36" wide by 80" tall. Bedroom and bathroom doors are typically 28"-32" wide. Closet doors range from 24"-36". ADA requires a minimum 32" clear opening width.
What is a rough opening for a door?
A rough opening is the framed opening in the wall where the door unit fits. For interior doors, add 2" to the door width and 2.5" to the height. For example, a 36"×80" door needs a 38"×82.5" rough opening.
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