Pre Eng building canopy 2

[nilaypathak]

On top of the Exterior door, contractor install canopy. Size of canopy is 1.2mt wide and 1.8mt long. Because of snow drift, snow load on that canopy called for 10 Kpa. Which engineer wants to confirm.
Is it make sense to consider 10kap load to design this small canopy?
Please share any thoughts

 

[MikeHalloran]

PEMBs are reputed to have essentially zero safety margin.
Be careful what you hang it on.


Mike Halloran
Pembroke Pines, FL, USA

 

[BAretired]

I note that you are from Alberta, Canada. The Alberta Building Code provides snow loads and some guidance for this situation. Why don't you use it to determine design criteria? Most members of this forum don't know the conditions in your area, so you must make reasonable judgments on your own.

It does not seem likely that a 10 kPa snow load on such a small canopy would have significant cost ramifications, so why not just stick with the code?

BA

 

[Ron]

Both of the above responses are right on target. A PEMB has little margin to add anything.

As for 10kpa...yes, that's a bit high, but considering where you are located and the drift because of the geometry of the canopy, it is probably not unreasonable, since you wouldn't want the entry blocked by a collapse.

Do as BAretired noted...follow the code. When you compute the drift, you'll find that because your canopy is short, your trapezoidal load distribution won't vary much from front to back of the canopy.

 

[beton1]

Can you use a separate support structure, as the PEMB likely has little reserve to accomodate?

 

[seimike]

You might also consider sliding snow with impact if the upper roof slopes downard toward the canopy and the upper roof does not include a mechanism to alleviate this condition