Interior door sizes: US, EU and Middle East standards for importers

Half of all door disputes start with a size mismatch. This guide sets out the sizes that actually ship in each market and the four numbers you must confirm before production.

The four numbers that decide everything

Regardless of market, a door order must fix:

• Leaf width × leaf height × leaf thickness (the door itself)
• Wall opening (structural opening), not the finished opening
• Frame/jamb type and its rebate
• Wall thickness the frame must cover

Give suppliers the wall opening and wall thickness as well as the leaf size — that is what decides whether a pre-hung set fits without on-site cutting.

United States and Canada

Imperial sizing dominates: common interior leaf sizes are 24, 28, 30, 32 and 36 inches wide and 80 inches high, with 1⅜ inch thickness for interior doors and 1¾ inch for exterior and many commercial doors. Door slabs are often ordered pre-hung in a jamb with a bore and hinge prep. Buyers who order metric sizes for this market usually regret it.

Europe

Metric sizing with a modular logic: 60/70/80/90 cm widths and 200/210 cm heights are the familiar family, with 40 mm leaf thickness common for interior doors. DIN-style frames and rebated jambs are normal, and fire-rated doors carry a class (for example EI30) plus a certificate the authority will ask for.

Middle East, Africa and Southeast Asia

Both systems appear, often in the same project. Metric sizes are usual in new high-rise work, while hotels built to US specifications keep imperial openings. This is the market where you should never assume — ask the contractor's shop drawings for the opening schedule.

Practical checklist before ordering

• Send a sample door or the exact leaf drawing for approval
• Confirm metric or imperial and mark the unit on the PO
• Confirm left-hand or right-hand handing and inswing or outswing
• Confirm whether frames are included, and the wall thickness they cover
• Agree packing that protects edges — corner damage is the most common transport claim