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Door headroom = 79.5" above threshold - - is this OK?

Y

Yikes

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CBC 1010.1.1 says "The minimum clear opening height of doors shall not be less than 80 inches". Is the threshold an allowable encroachment into this 80"?

My client's existing small office building (circa 1990s) has an exit door that is nominal 80" high above the adjacent floor, but because it has a 1/2" high threshold, the CASp is saying that it only provides 79 1/2" clear height, and the CASp report recommends removing and replacing the doors and frames to achieve 80" clear height.

Is there such a thing as dimensional tolerance or encroachment of a threshold for nominal 80" doors?
Also, what about the stop at the head of the door - - does it also reduce code-required clear height?
 
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I assumed that doors are standard sizes. Does chapter 11B have a code section for the door opening height? If not, why would a CASp be concerned with that. As an inspector I would not be concerned with 1/2” and the door stop is another 3/8” that would not concern me.

People generally do not step on the threshold so the opening height is relative to the floor. A 6’8” tall person is rare and aware.
 
Sorry Ice, I disagree. 32x80 is minimum clear dimension. That’s the low end of the tolerance, and there’s plenty of room on the other side. It’s kind of a chickensh1t thing to write up in s report, unless you are an auditor and you need to justify your fee.

I’m going through the same issues with an architectural firm who has a side business doing ADA audits. Got dinged last week, complete with picture: in the parking lot, asphalt pavement abuts concrete sidewalk ramp. The asphalt has shrunk back a little and now i have an opening exceeding 1/2” that creates a hazard. 302.3 Openings. You have to get down on your knees are look closely, but it’s there.
 
There is some leeway for typical projections:

1010.1.1.1 Projections into clear width. There shall
not be projections into the required clear width lower
than 34 inches (864 mm) above the floor or ground.
Projections into the clear opening width between 34
inches (864 mm) and 80 inches (2032 mm) above the
floor or ground shall not exceed 4 inches (102 mm).
Exception: Door closers and door stops shall be
permitted to be 78 inches (1980 mm) minimum
above the floor.
 
A CASp report is a statement of facts. As such there is no obligation to do anything. The likelithood of being sued over a half inch in door opening height is so slight as to not exist.
 
E37-07/08 Part I, submitted by AMMA, attempted to reduce the clear height to 78" for entry doors in nonresidential buildings. The IBC Egress Committee, in their ignorance, rejected the change saying it would be confusing and kept the 80" dimension even though I don' believe that there is a "standard" 6'-0x80" entry door on the market that meets the requirement. AMMA states that door leaves are manufactured in 2" increments.
E37-07/08 Part II, also submitted by AMMA, was successful in reducing both the clear opening width and height for entry doors in the IRC.
 
OK, maybe I should have posted this originally in the Commercial Building Codes subforum, because even though the comment was in a CASp report, the code requirement really comes from CBC Chapter 10.

bill1952, yes it has been like that since first occupancy.

It appears the basic question for this forum is, does the presence of a 1/2" raised threshold mean that I measure door opening height:
(a) from the adjacent floor, or
(b) from directly on top of the threshold?
 
Odd the IRC says only the egress door clear height opening needs shall be not less then 78" in height above the top of the threshold to the door stop. But the IBC says the height of the door opening shall not be less then 80" with nothing about a threshold or floor.


Also the IBC has an exception on door stops which can be 78" above the floor (not threshold) but nothing about door closer.
 
Rick18071 said:
Odd the IRC says only the egress door clear height opening needs shall be not less then 78" in height above the top of the threshold to the door stop. But the IBC says the height of the door opening shall not be less then 80" with nothing about a threshold or floor.


Also the IBC has an exception on door stops which can be 78" above the floor (not threshold) but nothing about door closer.
Click to expand...
Different committees.
 
ADAguy said:
ADA requires removal of pre-ADA existing barriers, no grandfathering
Click to expand...
Sorry, I thought the referenced 1010.1.1 was MOE, not accessibility. How does that quarter inch of height prevent discrimination against people with disabilities?
 
( = = = )
" Is being 6'8" a disability? "
Click to expand...
Not necessarily, but everything seems to be subjective
these days in the current Nanny State & Land of Litigation.

( = = = )
 
I believe that you can be somewhat flexible on some things. By the letter of the code this probably would not comply. If I were doing the inspection and actually measured it I would be flexible and approve the half inch. Most construction specs give you plus or minus 1/4". I don't believe it is detrimental to safety. If the wording says from the floor you could still not have the clear measurement if there is tile or carpet. I know some guys that will write up a grab bar for a 1/4" to high, I would not. I'm sure some will agree with me and some won't.

As for the residential height they may have taking in to account that thresholds are about 1 1/2" or could be the occupants are more familiar with the structure.
 
Here is the commentary. You could consider the threshold as hardware and is exempt?


This section of the code provides specific allowances
for projection into the required clear widths of means
of egress doors. These allowances directly correspond
with the method of measuring the required
clear width of the door as specified in Section
1010.1.1. A reasonable range of projections for door
hardware and trim has been established by these
requirements. The use of the means of egress door
by a wheelchair occupant will not be significantly
impacted by small projections located in inconspicuous
areas. The key to these allowances is their location.
Projections are allowed at a height between 34
inches (864 mm) and 80 inches (2032 mm). Below
the 34-inch (864 mm) height, the code does not permit
any projections since they would decrease the
available width for wheelchair operation. The full 32-
inch (813 mm) width must be provided at this location.
At 34 inches (864 mm) and higher, projections of
up to and including 4 inches (102 mm) are permitted.
The 4-inch (102 mm) projection is consistent with the
allowances of Section 1003.3.3. This section permits
door hardware, such as panic hardware, to extend
into the clear width, yet maintain accessibility for persons
with physical disabilities [see Commentary Figure
1010.1.1(2)].
Allowance must be made for door closers and
stops, since their design and function necessitates
placement within the door opening. The minimum
headroom clearance for door closers and stops is
allowed to be 78 inches (1981 mm) [see Commentary
Figure 1003.3.1(1)]. The 2-inch (51 mm) projection
into the doorway height is reasonable since these
devices are normally mounted away from the center
of the door opening, thus minimizing the potential for
contact with a person moving through the opening.
This is consistent with the exception in Section
1003.3.1. Other items that are mounted at the top of
the door opening, such as an electromagnetic lock on
a pair of doors, would still require an 80-inch (2032
mm) minimum headroom.
While this section deals with door hardware projection
within the clear door opening width, door hardware
projection into the required width of corridors,
aisles, exit passageways and exit discharge is
addressed in Section 1005.7.1.
 
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