Roof live load capacity
Roof live load capacity
(OP)
My client would like to build a roof deck on their NYC apartment, and I am looking at the live load carrying capacity of the existing roof of an old industrial building from the 1920's. The roof structure is 10" steel beams approximately at 6ft OC with an old style concrete deck.
I have run into this a few times now, but there is a lot of dead weight on these decks from the cinder fill (>120psf), and the roof has really no spare capacity whatsoever to the point of not even being ok for snow loads.
Has anyone else had similar experience?
I have run into this a few times now, but there is a lot of dead weight on these decks from the cinder fill (>120psf), and the roof has really no spare capacity whatsoever to the point of not even being ok for snow loads.
Has anyone else had similar experience?






RE: Roof live load capacity
or, reinforce the existing roof to take the existing and new loads, so more steel joists and reinforced beams.
RE: Roof live load capacity
RE: Roof live load capacity
If the existing roof deck is that recent there should be available drawings no? why don't they contact the engineer that designed that one?
RE: Roof live load capacity
"Flat, slope up to 20 degrees (1/3)": 40 PSF
"Steep, slope over 20 degrees (1/3)": 30 PSF
This is from page 265 of the 1923 Carnegie Pocket Companion. This book is available (free, of course) at this page of my website:
http://www.slideruleera.net/miscellaneous.html
It is reasonable to assume that these loads remained in force for all of the 1920's since they remain unchanged in the 1932 NYC Building Code, as quoted in the 1934 Carnegie Pocket Companion (have not finished scanning that one).
www.SlideRuleEra.net
www.VacuumTubeEra.net
RE: Roof live load capacity
RE: Roof live load capacity
http://www.gostructural.com/magazine-article-gostr...
http://www.rci-online.org/interface/2009-04-koziol...