Insurance are trying to worm out of paying for my garage/shed roof where the felt covering was ripped off by a strong gale.

By chance I saw something on “Winterwatch” last night where they said their expert had calculated their shed roof had experienced 6 tons of lift in a storm similar to an aircraft wing. Looking at the profile of my roof I think it would also behave like a wing and suspect the felt was “sucked off”. I’d like to simulate this – are there any free online tools where I can put in dimensions and test this out?

Shed/garage side profile is as below…. Where I wrote vacuum is where I think the low pressure would occur and corresponds with the damage.

EDIT – Ignore picture, it didn’t work!
WIND——————>

…….x ————->
…x…….x vacuum? —————–>
x…………..xxxxxxxxxxxxxxxxxxxxxxxxxxx
x………………………………….x
x………………………………….x
x………………………………….x
x………………………………….x
x………………………………….x
x………………………………….x

MY OH is a bit of a wiz in this, but he reckons you could get a reasonable estimate with hand calcs.
If you can’t estimate it with hand calcs any simulation you do will just be pissing in the wind. 😆

Is it worth claiming?

a 20m roll of heavy duty green mineral felt is only £40

Dbcooper – Just looked and that is Linux only. I guess the calcs to do it properly would be pretty complex

Jota180 – A large area of of it is flat roof, so would need doing properly to avoid leaks – think it is probably around 25m^2

Strangely, just had a lunchtime CPD with a wind Micro-Climate engineer.
They use CFD to provide comfort level windspeeds for use in building design decisions for urban realm effects, but for negative pressure values use a model in a wind tunnel, otherwise they’d end up taking too much time to run the calcs as unlike my SO they don’t have a Cray CS400 to use…

Winterwatch OMG

Its turned into Top Gear with Squirrels