Homeowner Forum / Construction / August 2006

I'm planning on building a maintenance access to the main roof on my
building and instead of using a pull down ladder I want to install a
permanent "staircase."  In order for this staircase to work it needs to
be steep -- much like some staircases in Amsterdam.  The rise of the
staircase is around 10' and the run is 6' which makes this violate
standard building codes but since this is strictly for maintenance
access to the roof I think this might be OK.  I've been googling the net
to figure out how the dimensions used by the dutch for their steep
staircases and can't seem to find anything.  The typical max for US
building code (as far as I read) requires a max step height of 8 1/2"
with a 9" tread.  This won't work in my situation.  In order for me to
figure this out mathematically I'd like to know how I can get this
staircase steeper in order to reach the landing.

Does anyone know of a resource (book or web site) where I can learn how
to design this including acceptable non-standard dimensions?  I read
about those alternating step steep staircases and I'd rather go with a
regular straight run.  I could get a pull down ladder which would be
even steeper but those ladders are kind of cheezy and I think I can put
in a more permanent structure that would be less steep and look nicer.  
Right now I'm just planning the project and hope to start building in
January and opening the roof next April.

Ironically I was just in Amsterdam last month but forgot to bring a tape
measure.