Exterior Stairs 1

[kxa]

I have a project to design outside stairs for two-story apartments. I need to compare different options such as concrete, steel or a combination. The structural framing for the bldg is steel so even if I propose concrete staircase I would have to have metal in it for attachment to the steel framing of the bldg. I also have to be concerned with the snow, ice and salt which can cause corrosion.

Are there any references or guidelines that I should be looking into or follow?

Thanks in advace.

 

[ChipB]

Snow, ice, and the resulting salt are going to happen. More of a maintainence problem. I like putting stairs on someone else. A little trick I learned when I worked for a steel fabricator. Try a little note pointing to the stairs which states, "Metal Pan Stairs by Steel Fabricator" and be done with it. Now, if the architect is trying to make a statement with the stairs, it won't work. But, generally, it does. FWIW, this is generally the least costly stairs for this type of building.

 

[Lion06]

Following the same idea as ChipB, we usually have stairs as a performance spec. That means someone else designs it and just sends the calcs to us for review. It beats the heck out of designing them.

 

[dik]

Also, if in steel and exposed... call for Architectural treatment of finishes... connections, welds, etc.

Dik

 

[COEngineeer]

thats what i put all the time. "something" per manuf.

If the stair fails, who to blame? The manuf. of course because you put it on your drawing PER MANUF.

 

[Lion06]

COEngineer-
Don't you still have some responsibility? Do they submit calcs and plans for your review? We always review performance specs to make sure it is not interacting with the overall structure in a way that we don't want as well as for coordination items.

 

[jike]

If the stair fails, who to blame?

This is a very complicated legal question that even our legal profession cannot agree upon. What usually happens is that everyone (even remotely involved) gets sued and it is up to the attorneys and insurance companies to sort it out.


If the stairs is of any significance, I recommend that your performance spec requires an insured, licensed engineer be hired by the fabricator to design the stairs, not just a detailer.

 

[DaveAtkins]

I wonder if this type of stair even meets current codes. I seem to remember that, with the IBC, an exterior stair which is unprotected from the weather cannot be considered a means of egress, because of the snow and ice that can form on the treads.

DaveAtkins

 

[ChipB]

Dave,
Doesn't the snow and ice increase the performance for evacuation? If there is a fire, and all residents are vacating, one person slips at the top, the whole kit and kaboodle come tumbling down. Isn't that why it's called a landing? :-D
Chip
P.S. Is it Friday yet?

 

[IceNine]

It's friday in New Zealand

 

[csd72]

IceNine,

Thats okay, we are still on our weekend when you go back to work on Monday.

csd

 

[kxa]

Well, I did not certainly think I get so many responses. I too look forward to Friday!! From what I read, I get the Impression that everybody is trying to pass the buck for that matter the responsibility to the manufacturers. What many are saying is that why would the client even need an engineer. He could write his own performance spec. Just request bids for stairs that, let’s say, last 15 years or so.

I think we as engineers should be able to spec the materials and do the structural design. That was the intent of this posting. If we don’t know how something may perform how can we accept it? The manufacturer or the contractor may not be around a few years down the road.

I was looking for guidelines/publications that would help me come up with recommendations and perform the necessary designs/details. Is anybody aware of any resources?

Thanks,

 

[jike]

There is a Metal Stairs Manual by NAAMM, the National
Association of Architectural Metal Manufacturers. I don't know if it is still available. You might try your local library or eBay.

 

[Lion06]

kxa-
I didn't mean to imply that someone who is not an engineer be designing the stairs. I was just saying that given the complexity and amount of time and detail that must be put into the building design it is ususally not time well spent designing stairs. As the EOR we have too many other design tasks, and with short time frames for CD documents this is something that can be easily performanced spec'd.
Also, with the performance spec - the calcs still have to be signed and sealed by a Professional ENGINEER, not a detailer or anyone else.
Are you doing the building design and ALSO want to design the stairs, or are you thte guy that the stairs got sent to?