# Steel bracing protruding from wall - overhead obstruction?



## Yikes (Nov 17, 2009)

I have a steel-framed elemtary school building.  On on wall of each classroom, there is a diagonal steel brace (for lateral forces) that  - in plan view - sticks out about 8" from the wall.  In elevation view the brace is angled about 30 degrees, and protrudes from the ceiling and dies into the floor at the corner of the classroom.  Our California Building Code 1133B.8.6.1 says that any obstruction below 80" high must not stick out more than 4" at "walks, halls, corridors, passageways or aisles".  This situration occurs nowhere near the exit doors.

Question: the local inspector is basicaly saying that anywhere in the classroom is a "walk", because you can walk over to it, thus we have a clearance problem.  I think that the language of CBC is specific enough that its applicaton is limited to areas where people are intended to walk, and it would not apply to the back wall of a classroom.  What do you think?


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## Paul Sweet (Nov 17, 2009)

Re: Steel bracing protruding from wall - overhead obstruction?

Many classrooms are arranged to have aisles around the perimeter.  On the other hand, desks could be rearranged if there is a visually impaired student in the classroom.


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## TJacobs (Nov 18, 2009)

Re: Steel bracing protruding from wall - overhead obstruction?

Why can't it be enclosed?


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## JBI (Nov 18, 2009)

Re: Steel bracing protruding from wall - overhead obstruction?

"the local inspector is basicaly saying that anywhere in the classroom is a "walk", because you can walk over to it, thus we have a clearance problem."

That doesn't leave too many places in any building that would NOT qualify as a 'walk' in his interpretation.  :roll:  I don't agree, but not sure what section to throw back at him... Normally structural components aren't considered 'obstructions', are they?

EDIT: OK, the CA codes are in the I-Codes free view selections,  

_1133B.8.6 Protruding objects. _

_1133B.8.6.1 General. _

_Objects projecting from walls (for example, telephones), with their leading edges between 27 inches (686 mm) and 80 inches (2032 mm) above the finished floor, shall protrude no more than 4 inches (102 mm) into walks, halls, corridors, passageways or aisles. Objects mounted with their leading edges at or below 27 inches (686 mm) above the finished floor may protrude any amount. Free-standing objects mounted on posts or pylons may overhang 12 inches (305 mm) maximum from 27 inches (686 mm) to 80 inches (2032 mm) above the ground or finished floor. Protruding objects shall not reduce the clear width of an accessible route or maneuvering space. See Figure 11B-7A. _

Is the object in question actually 'projecting from' the wall, like the telephone example provided? OR Is the object in question a component of the wall?

Is the object in question reducing the 'clear width of an accessible route or maneuvering space'?

I think he's reaching...


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## Gene Boecker (Nov 18, 2009)

Re: Steel bracing protruding from wall - overhead obstruction?

We have the same condition here in our office.  A piece of diagonal seismic bracing runs from above the ceiling to the floor.  It is located next to one of the aisles for access to the "cube farm."  Yes, it's an obstruction and needs to be "protected."

Unless, the diagonal member is located in an area where walking cannot happen - such as by a bookshelf or cabinet, then an aisle could be located there and the headroom issue is real.

I'd suggest looking at the final furnishings layout to determine if any element will be able to act as a warning.  If not, then some detail will need to be done to provide the necessary warning for the "head-banger potential."


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## Yikes (Nov 18, 2009)

Re: Steel bracing protruding from wall - overhead obstruction?

FYI, some additional info.:

During plan check, the State (DSA) plan checker specifically looked at this issue and said it was OK.

The local school district has decided to hire their own independent inspectors.  It is this inspector who is having a problem with it.  The school doesn't want to enclose the space under the brace because (a) it may block windows in some classrooms, and (b) it will reduce the square footage.  They may consider adding cubby holes below it, but they want to avoid a change order if it's nto necessary.

Gene, I can see your point, if the furnishings of the classroom will ultimately create an aisle adjacent + parallel to the brace, then there might be a potential application of 1133B.8.6 to the situation.

I would not describe the brace as "projecting from" the wall.  It is a freestanding obeject, but it is not mounted on a post or pylon - - it IS the post or pylon, albeit at an angle that is not true vertical.

Obviously, the "spirit of the law" is to reduce the likelihood of someone bonking their head on an overhead obstruction, without warning.  But there are all kinds of situations where an angled wall (something other than vertical) or a sloped roof on a pony wall (like in a finished attic) would have the potential for a head 'bonk', but it's allowed and we don't worry about that because there's no sharp edge or corner.  I don't think there will be a sharp edge in the only direction of travel that has any potnetial of a head bonk.


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