Re: Snow load evaluation

[AZ Woody <reply@here>]

Simple solution here!

Step outside and look!

Hey..  I grew up in "snow load" areas..  Look at the roof and say "darn!
  I need to do something!"

Lewis Gardner wrote:
> L. M. Rappaport wrote:
>
>> 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 used to do something like this in my last garage.
>
> That garage lacked a BIG A** beam to connect a hoist for lifting motors
> and other big stuff. As a workaround I placed a 2" steel pipe across 5
> roof trusses and connected the chain hoist to the mid point. Using a
> tape measure I would check the deflection of the middle truss. As long
> as it was less than .5" (20' span) I didn't worry.
>
> If I were to attempt a similar snow load sensor I would measure the mid
> span deflection of a rafter in the middle of the largest lowest pitched
> section of the roof. There are no magic numbers to go by but over time
> you might be able to get a feel for "well the snow in 07 deflected the
> rafter .25" and the house didn't collapse" so this snowfall is not that
> bad (yet)!
>
> Just a thought...