Re: Snow load evaluation

[nobody@xxxxxxxxxxxx (Dave Houston)]

L. M. Rappaport <nospam@xxxxxxxxxxx> wrote:

>On Sun, 11 Feb 2007 11:58:05 -0500, "Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>
>wrote (with possible editing):
>
>>Anybody doing anything automated in terms of detecting an excessive snow
>>load on a structure's roof?   I saw a news report about upstate NY where a
>>guy said "when your doors begin to stick, that's when it's time to clear the
>>snow off the roof.  It's good to know one of the warning signs but surely
>>there's got to be a better way!
>
>You could put stress gauges on the roof rafters, but you'd still have the
>problem of calibration.  There are just too many variables - rafter size, rafter
>spacing, decking, shingle material, water content of the snow, ice, etc - to be
>able to do this in advance.

I think it would be difficult to use strain on the rafters as an indicator
with a rather evenly distributed load like this. Even wind might have as big
an effect as snow.

If you could place load cells to measure the weight on the roof, you should
get reliable data that correlates with snow load.

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