On 02/29/2016 3:25 PM, Don Y wrote:
On 2/29/2016 2:18 PM, wrote:
....

Since we started here I have been measuring all the doors I see and
the answer I come up with is there is no standard.
I have anything from "right on" to a 1/2" smaller and one that is
about 1/4" smaller (steel door so I know it wasn't modified).
My guess is that manufactures make doors for standard rough openings
and the thickness they choose for the jam determines the actual door
size.

(for PREHUNG doors)

I am curious how building inspectors deal with clear opening sizes for
accessible routes since even a full size door is smaller because of
the stops.

I expect lots of variation on *interior* doors. But, I figured exterior
door would have far less wiggle room!

Nope as I told you some several responses above...they build to a RO and
the final interior opening turns out to be what it is--the two of -1/2"
and -1/4" are pretty common for width but the length (height) is also
dependent upon those factors plus how they design the threshold.

If you're trying to order a door slab to fit an existing opening, see
above as well, there's a whole lot more besides just the exterior
dimensions to worry about, especially if you're talking steel, not wood,
where field modification is much more of a trick...particularly things
like number, size, placement and setback of hinges, hole locations, etc,
etc., etc., ...

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