You are standing in the door aisle at Home Depot trying to remember which way your bathroom door swings. The pre-hung doors are priced and stacked, but the labels say “left hand inswing” and “right hand outswing” and you are not sure which one matches your house. This is the most common stumbling block in any door purchase. The difference between a left vs right hand door is a 30-second test if you know the convention — but pick wrong and you go home with a $200 mistake that the store will not always take back.
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The Standard Convention
Door handing is determined by where the hinges sit when you stand on the outside of the door, facing it as if you were about to enter. If the hinges are on the left side, the door is a left-hand door. If the hinges are on the right side, the door is a right-hand door.
This convention applies to exterior doors and to most interior doors throughout the U.S. The few exceptions involve closet doors that open outward into a hallway and reversed-handed locksets, but the convention itself is consistent across manufacturers.
Inswing vs Outswing
Handing tells you which side the hinges are on. Swing tells you which direction the door moves. Together they define one of four configurations.
- Left hand inswing: Hinges on left, door swings away from you into the room when you open it from outside.
- Right hand inswing: Hinges on right, door swings away from you into the room.
- Left hand outswing: Hinges on left, door swings toward you when you open it from outside.
- Right hand outswing: Hinges on right, door swings toward you when you open it from outside.
Interior doors are almost always inswing — they open into the room being entered. Exterior doors in most American homes are inswing too, with outswing reserved for storm doors, shed doors, and commercial applications.
The Test Every Time
Use this 4-step test in 30 seconds at the door you want to replace.
- Stand on the outside of the door — the side from which you would enter the space.
- Look at which side has the hinges.
- If hinges are on your left, it is a left-hand door. If on the right, it is right-hand.
- Look at which direction the door opens. If it opens away from you, it is inswing. If it opens toward you, it is outswing.
For an interior door, the outside is whichever side you stand on most often when entering. For a bedroom door, that is the hallway. For a bathroom door, that is also the hallway. For a closet door, that is the room outside the closet.
Why Manufacturers Care About Handing
Pre-hung doors come from the factory with the hinges already mortised into the jamb, the strike plate already installed, the weatherstripping already cut, and often the lockset bored. All of these are handed — they are not symmetrical. Mounting a left-hand door in a right-hand opening means cutting new hinge mortises, drilling a new strike plate, and reversing the lockset, which takes hours.
For slab doors (no frame), most are reversible — you can drill the lockset hole on either side. But pre-hung doors are locked into one handing from the factory.
Lockset Handing
Most cylinder locksets from Schlage, Kwikset, and Defiant are reversible — they install on either-hand doors. Lever-style locksets, however, often need to be set for the correct handing before installation. The lever needs to point downward in the latched position regardless of which side the door is on.
Mortise locksets — common on commercial doors and high-end residential entry doors — are usually handed and cannot be reversed without sending the lock back to the manufacturer. Check the box carefully before installing.
For exterior deadbolts, handing rarely matters. The bolt itself is symmetrical and the thumbturn can flip if needed.
When You Need an Outswing Door
Outswing doors solve problems that inswing doors cannot. In a tight bathroom, an inswing door can leave only inches of clearance once installed. An outswing door — opening into the hallway instead — frees the bathroom floor space for fixtures.
Outswing exterior doors are also common in hurricane zones along the Gulf Coast and parts of Florida. Wind pressure on an outswing door pushes against the frame, holding it shut, while wind pressure on an inswing door tries to push it open. The Miami-Dade code allows outswing entries with enhanced hinges and security strikes.
The downside of outswing doors is the exposed hinge pins. A burglar can pop the pins out of an outdoor-facing hinge in seconds. Use security hinges with set screws or non-removable pins on any outswing exterior door.
Measuring Before You Buy
With handing determined, measure the rough opening. Pre-hung interior doors typically need an opening 2 inches wider and 2-1/2 inches taller than the door slab. A 30-inch door needs a 32-inch by 82-1/2-inch rough opening.
Measure the jamb width too. Most interior walls use 2×4 studs with 1/2-inch drywall on each side, for a jamb width of 4-9/16 inches. Older homes with 3/4-inch lath and plaster need a 4-3/4-inch jamb. Exterior walls with 2×6 studs need a 6-9/16-inch jamb.
Pre-hung doors come in standard jamb widths, and matching the wall thickness avoids needing to add extension jambs after installation. Take a tape measure to a small section of wall before driving to the store.
Common Mistakes to Avoid
Three errors send homeowners back to the store. The first is determining handing from the inside of the room — always work from outside. The second is buying an inswing door for a tight bathroom where it will collide with the toilet or sink. Sketch the swing arc before buying.
The third is ignoring the wall switch position. Light switches typically sit on the latch-side of the door so you can reach them as you enter without walking around the open door. A reversed-handed door puts the switch behind the open door, which is awkward to live with every day.
