Historical NBCC Parking Structure Live Loads (Canada)
Historical NBCC Parking Structure Live Loads (Canada)
(OP)
I need to know the code specified live loads for parking structures according to the 1977 and 1980 versions of the National Building Code of Canada. I've been led to believe that, at some point in time, the loading dropped from 3.6 kPa to 2.4 kPa. If anyone has some dusty NBCC's on their bookshelf, it would be a great help.
Thanks,
KootK
Thanks,
KootK
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.






RE: Historical NBCC Parking Structure Live Loads (Canada)
RE: Historical NBCC Parking Structure Live Loads (Canada)
2.4 kN/m2 for garages used by passenger cars,
6.0 for garages for unloaded buses and light trucks,
12.0 for loaded buses and trucks and all other trucking spaces.
I don't immediately see the 1977 NBC, but both my 1965 and my 1970 NBC both gave 50 psf, 125 psf and 250 psf for the above 3 categories, which us the same loading as listed above. So I would think the 1977 NBC is the same.
However, my 1960 NBC gave 75 psf for passenger car garages.
The 1968 City of Toronto Building by-law (which we used to call the Toronto Building Code) specified 75 psf for garages for passenger cars (75 psf = 3.6 kPa). My recollection is that for buildings in Toronto we used the Toronto Building Code until 1975 when the Ontario Building Code took over.
I think though that you should check your provincial Code to be absolutely sure, because it may be that the provincial Code did not necessarily follow the NBC.
RE: Historical NBCC Parking Structure Live Loads (Canada)
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Historical NBCC Parking Structure Live Loads (Canada)
BA
RE: Historical NBCC Parking Structure Live Loads (Canada)
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Historical NBCC Parking Structure Live Loads (Canada)
Prior to 1974, there was no Alberta Building Code. The City of Edmonton followed the Uniform Building Code as far as I can remember. I can't be certain about the design load for parking structures at that time but I would be surprised to learn that it differed from the current value of 50 psf (2.4 kPa).
In all editions of the Alberta Building Code, the structural aspects of the code, including loads for various uses and occupancies, have been taken directly from the NBC.
BA
RE: Historical NBCC Parking Structure Live Loads (Canada)
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Historical NBCC Parking Structure Live Loads (Canada)
Why do you ask the question? If you are reviewing an old garage, there may be some reduction in strength if it has not been kept in good repair, or if the repairs have not been carried out properly.
There is of course the requirement to resist concentrated loads as well - these are most likely critical for relatively short spans.
Interestingly, but not really relevant to your question, the 1949 NBC gave the loading as 100 psf!
RE: Historical NBCC Parking Structure Live Loads (Canada)
RE: Historical NBCC Parking Structure Live Loads (Canada)
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Historical NBCC Parking Structure Live Loads (Canada)
If I remember correctly, Harold Collins, Chief Building Inspector for the City of Edmonton in the 1970's held the view that Alberta should adopt the UBC in preference to the NBCC because he believed it dealt more thoroughly with most issues and was easier for plan checkers to interpret than the NBC. I hope I am not misquoting him as he died quite a few years ago and is unable to refute or clarify my comment.
http://en.wikipedia.org/wiki/Uniform_Building_Code
BA
RE: Historical NBCC Parking Structure Live Loads (Canada)
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Historical NBCC Parking Structure Live Loads (Canada)
RE: Historical NBCC Parking Structure Live Loads (Canada)
1) Use the NBCC commentary appendix L to lower my load factors. Gamma_LL = 1.20; Gamma_DL_1.08. It's not ideal but it's easily justified based on the code provisions.
2) Lower my live load from 50 psf to 30 psf. In several parking industry design references, I've seen statements saying that, statistically, a fully loaded parking structure is only subjected to a live load of 25-30 psf. I feel that this will be particularly true for my underground residential parking facility as it's unlikely that there will be heavy trucks down there.
Obviously, employing both of these strategies simultaneously makes for a very aggressive analysis. At the same time, my gut feel is that the existing structure will be fine. But, then, what does my gut know really?
The question: how crazy do you think this is? Be merciless...
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.