Definition
What it means.
- Clear opening width
- A door labeled "32 inches" describes the door slab or the rough frame, not the space an object can pass through. The clear opening width is what remains once the open door leaf, hinges, stops, and any hardware intrude into the gap, typically an inch or more less than the nominal width. ItemFits always solves against the clear opening, not the nominal number, because that is the dimension a sofa actually has to clear.
- ADA minimum clear opening width
- 32 in Source: ADA Standards §404.2.3
In depth
The fuller picture.
Nominal size versus the gap that is left
A door is sold by a nominal size that names the slab or the rough frame, not the space an object passes through. By the time the leaf is open, the hinges, the stops, and the door slab itself all intrude into the gap, so the clear opening is typically an inch or more narrower than the number on the box. A 36 inch nominal door commonly leaves about 34 inches of clear width, and a 32 inch nominal door can fall short of the 32 inch accessible clear minimum entirely.
Because this gap is what an item actually has to clear, ItemFits always solves against the clear opening rather than the nominal size. The accessibility standard is built the same way: the ADA states its 32 inch minimum as a clear opening measured with the door open 90 degrees, and it rises to 36 inches when the opening is more than 24 inches deep, such as a thick wall or a vestibule.
Measure it
How to measure.
In practice
How it shows up.
A door sold as 36 in nominal often yields only about 34 in of clear opening width once the open leaf and stop are subtracted, which is the number ItemFits checks a couch against.
Go deeper
Related terms and tools.
Frequently asked
Questions we keep getting.
Is clear opening width the same as the door size?
No, the door size is the nominal slab or frame; the clear opening is the smaller, unobstructed gap left once the open door leaf and stop are subtracted.
01How much narrower than nominal is the clear opening?
Usually about an inch or more. A 36 inch nominal door often leaves roughly 34 inches of clear opening once the leaf and stop are subtracted.
02Does taking the door off its hinges help?
Often yes. Removing the leaf reclaims the width the open slab and its hardware were eating, which can be the difference for a tight piece.
03How is the clear opening measured?
Horizontally between the face of the door open 90 degrees and the stop on the opposite jamb, which is the same way the ADA measures it.
04