Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Snow Drift load in Roof Valleys

[Subject Prev][Subject Next][Thread Prev][Thread Next]
I completely agree that there is valley loading and I think it is already is in the IBC.  Where you have a valley you have a ridge.  Where you have a ridge you have unbalanced loading.  The unbalanced loading diagrams could be created to give a conservative (and even similarly shaped) loading.  It may not be as big as the valley loading in the UBC, but there is still definitely a required check.

Jake Watson, P.E.
Salt Lake City, UT

---------- Original Message ----------------------------------
From: Daryl Richardson <h.d.richardson(--nospam--at)shaw.ca>
Reply-To: <seaint(--nospam--at)seaint.org>
Date:  Wed, 20 Oct 2004 10:30:24 -0600

>Mike,
>
>        If the code has omitted the need to design for an accumulation of
>snow in roof valleys the code writers have made a mistake.  Since it is well
>known by structural engineers working in snowy regions that excess snow does
>build up in valleys it would become the engineer's responsibility to make a
>reasonable allowance for this.
>
>        I would expect an errata will be published to correct his oversight.
>
>Regards,
>
>H. Daryl Richardson
>
>"Michael L. Hemstad" wrote:
>
>> List,
>> For gable roofs with intersecting ridge lines (i.e. for L-shaped
>> buildings), 1997 UBC Appendix Chapter 16, in Section 1641.3.2, dictated
>> an increased accumulation of snow in the valleys caused by the roof
>> intersections.  Figure A-16-12 shows a good picture of what I mean.  I
>> can't find anything like that in the IBC (I'm looking at 2000), only a
>> general unbalanced load for any gable roof, ignoring the valley effect
>> of such intersections.
>>
>> Does anyone have any background as to why the valley drift criteria were
>> not included in the IBC, or have I just not found it?
>>
>> Thanks,
>>
>> Mike Hemstad, P.E.
>> TKDA
>> St. Paul, Minnesota
>>
>> ******* ****** ******* ******** ******* ******* ******* ***
>> *   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
>> *
>> *   This email was sent to you via Structural Engineers
>> *   Association of Southern California (SEAOSC) server. To
>> *   subscribe (no fee) or UnSubscribe, please go to:
>> *
>> *   http://www.seaint.org/sealist1.asp
>> *
>> *   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you
>> *   send to the list is public domain and may be re-posted
>> *   without your permission. Make sure you visit our web
>> *   site at: http://www.seaint.org
>> ******* ****** ****** ****** ******* ****** ****** ********
>
>
>
>******* ****** ******* ******** ******* ******* ******* ***
>*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
>* 
>*   This email was sent to you via Structural Engineers 
>*   Association of Southern California (SEAOSC) server. To 
>*   subscribe (no fee) or UnSubscribe, please go to:
>*
>*   http://www.seaint.org/sealist1.asp
>*
>*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
>*   send to the list is public domain and may be re-posted 
>*   without your permission. Make sure you visit our web 
>*   site at: http://www.seaint.org 
>******* ****** ****** ****** ******* ****** ****** ******** 
>
 

 
______________ ______________ ______________ ______________



 
                   


******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********