Hello Carol, You raise an interesting issue and I have thought about ladders as well for such situations. One thing to keep in mind is that if what you design, especially regarding egress and human movement through the habitable finished space, has hazards, that you will likely inherit such risks. Every Board of Architecture indicates that an architect is to "Protect the Health, Safety & Welfare" of the public.
It may seem like an inconsequential thing to indicate a ladder going to part of the main, finished spaces of a house, but you could be opening yourself up to possible liability in the future, should someone fall and injure themselves on such a means of circulation. I have seen situations where I have labeled some space on my documents as "future bonus room" and not provided any means to get there, because it was not part of the initial project. I had imagined a future exterior stair to get there. Then months into the future, someone, perhaps a contractor, may have installed some questionable means to get to that space and finished it. That is not my liability: I didn't design that or indicate that solution on my documents or in writing. I would always prefer to have a code-compliant stair and I would always state that, in writing.
But exposing yourself to liability to solve a client's immediate desires to not spend what it would take to solve in a code-compliant manner is not something for which you are being paid. Be careful out there. If your client's family (or future owners) were hurt on your ladder, a smart attorney could haul you into court, open the IRC and ask you, on the witness stand, to show him and the court where it allows ladders to be used in habitable space...not a pleasant scenario. However, if your client fell down a code-compliant stair you designed, You could pull out the IRC and defend yourself and be acquitted. Designing to avoid liability may not be something that we think of as we try to solve client problems and help them achieve their goals, both functionally and economically, but if we cross that line, bad things can happen, both to ourselves and our clients, that in the heat of the moment may seem unimportant, until something unfortunate occurs.
And relying on a building department to supposedly erase your liability won't work. Any building department will tell you that they are not responsible for the design nor for the constructed project. Just because they allow something doesn't mean that our liability as architects goes away. Building departments have no contract with the owner, the builder or anyone else. We are all licensed by the State. That is who will hold us accountable, not the building department.
This does bring to mind attic fold-down ladders: why are they acceptable practice? I would think the answer there would be: that is not habitable space: that is a utility function and the owner doesn't even have to go there; licensed tradespeople might mainly use that to perform construction and maintenance duties. But those are my opinions and others may have found ways to deal with such things... if so, let's hear them. I wish you all the best.
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Rand Soellner AIA
Architect/Owner/Principal
Home Architects
Cashiers NC
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