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Fixed Industrial Stairs 1

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SAIL3

Structural
Oct 7, 2010
751
This supject has been posted before and there seemed to be no definite conclusion reached..so I am posing it again to see if there are any new insights or experience on the problem
..project is in the state of Georgia, US
...governing code IBC with GA amendments
problem...I am designing an outdoor industrial stairs that will be used for maintenance of equipment..
I am coming up with about 13'-7" between stair landings...
..OSHA does not place any limitations on the distance between landings,
IBC is not clear when it comes to industrial type buidings about
what limitations to apply..
..12'max is typically used in the industry..
If I have to adhere to this 12' max, it would entail alot of redesign and time on a tite schedule...
where did this 12' max originally come from?..
thanks
 
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I don't know the origin but I am currently working on an industrial project where we had a stair problem. We are replacing an existing stair in-kind that has a rise of 16 feet. The client made us follow the IBC code which involved re-design and re-detailing. I agrued that IBC is basically for commercial and residential construction and not industrial, but in the end the client is always right.
 
IBC Section 1009.6 - max. vertical height between floors or landings = 12 feet.

 
As you state that the IBC is the governing code, unless the GA amendments alters or allows other vertical rises for landings of industrial structures. Then per (2009 IBC) section 1009.7 the landings needs to be at 12' maximum vertical rise or 20' maximum with an alternating tread devices.
So unless you can get the building department to specify a differance code for your structure, you are stuck with the 12' vertical rise IMHO.

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.
 
If it's egress from part of a building, then you are stuck, but maybe it's not a building and not goverened by the building code. If it's a platform to which you could have ladder access but you are choosing to place a stair, then you might be able to convince a code official that your stair is not govered by the building code. I have sucessfully made this argument with building officials for industrial stairs (but I should note that I have lost this argument too).

It is heavily dependent on the official and on the situation. I tend to think that officials are too concervative and often ask for (or require) a full-fledged 36" wide, 7/11, 12' max rise stairs when an OSHA-comliant 24" wide steep stair or ladder will suffice.
 
Even the biggest knucklehead Plan Reviewer or Building Official knows that section of the code (12'-0" between landings) by heart. And there's no reasoning with them regarding this. So good luck.
 
Once again we see the absolute stupidity in the way OSHA and our bldg. codes force us to deal with these kinds of issues these days. Soon there will be no need for common sense or good judgement, or real thinking..., it’ll all be codified. With absolutely no need for common sense or flexibility which might save the job 1000 engineering hours and a million bucks. Imagine the confusion and total befuddlement if the AHJ (plan checker or inspector) had to make a common sense decision, without a full page of code verbiage to hang his hat on. If they give you 13'-7", then the next thing you know some real jerk will come along and want 13'-7.25", and where would it all end? The 12' btwn. landings was in the first UBC I used, the 1970 Ed. Undoubtedly some tech. writer determined that people navigating stairs should be able to stop and have a picnic every 12' of vertical movement, on a landing, to acclimate to the altitude change, no doubt. Besides, in those days we only had 12' rulers, those newfangled 16' tapes didn’t come along for a few more years. I do understand that you can’t climb a 2000' tall bldg. without a few landings and a lunch room at the 100th fl., but what’s magic about 12' is beyond me, except no decision maker has any incentive to stick his/her neck out for you. Consider yourself lucky, no one has suggested a ramp yet, have they?

I see three possible solutions to your dilemma: (1) Fill the entire site around this structure by exactly 1'-7" and your problem will go away. The AHJ will probably not require you to fill beyond the property lines. (2) Alternatively, you could cut 1'-7" out of all the vertical components in the bldg. and glue them back together. Again, problem gone. (3) Let them use a ladder, there is no 12' limit on those.

It’s hard to imagine that expecting a maintenance worker to take three more steps before reaching the next floor would be a dangerous or unsafe thing. And, a straight run might even facilitate the transport of equipment up the flight of stairs, but never mind, 12' is chiseled in stone, someplace, for some obscure reason.
 
Ironically I did a project about a yr ago with stairs that were 13'-6" to the fist landing and the angle was nearly 45º. They were for maintenance, not regular use so we got around the 12' max rise.
If it is not for regular use, IMO the code officials have no leg to stand on in terms of reason....especially when a ladder is the other alternative.
 
thanks for all the replies.....
since this is a super-fast-track project, I can not afford any uncertainties or delays in obtaining a building permit, so I have decided to redesign now and take the hit up front...much aggro!
I get frustrated also at the strict interpretation of the codes without using any engineering judgement or, for that matter, common sense..
the codes can not cover everything, nor do I want them to...they are cumbersome enough as it is...
to me ,the codes are to be interpreted by qualified users, using their best judgement..see blurb in the front page of the codes..
to ease the sting abit, I guess the local code inspectors have to deal with all kinds of shady and dishonest characters and have probably been burned many times for taking a risk or using independent judgement...as you can see, I am trying hard to move towards peace and serenity on this matter..
 
Peace and serenity are good, we all get too little of both of them in our life and business. Could you put a three step concrete stoop and landing at the bottom of a straight 12' stairs? Make that the lower foundation for the stair.
 
unfortunately, this problem is 29' up in the aie...
 
Sail3...it is not up to the plan reviewer to interject engineering judgment...that's your purview. They are sometimes not licensed professionals, just trained in plan review. Unfortunely, their interpretation of the code will almost always prevail over your interpretation.

dhengr...my thought exactly...great minds think alike! :)

 
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