Wind exposure factor in Canada

[CDLD]

Good afternoon!

I am having trouble making sense of the reference height definitions for wind loads using NBC 2015.

If you are designing cladding and girts, would you simply take the height of the element above the ground, or would you refer to 6) a) & b) below?

What I am thinking is that part a) & b) apply only to overall building design and part c) would apply to girts, cladding and secondary elements.

Thank you!

 

[KootK]

I see it exactly the same CDLD.

 

[CDLD]

Thanks for the reply.

It is strange that clause 7) only refers to buildings.
It feels inconsistent to use part 6)c) in combination with part 7)b).

The wording of 6)c) is not very clear; I wonder if this clause is tailored more towards miscellaneous structures than wall girts.

 

[jayrod12]

My interpretation for 7. b) being different than 6. c) is to do with the research that goes into the internal pressures.

Perhaps the testing/modelling didn't notice an appreciable difference in internal Ce values until you get up to the 20m tall building.