"Commander Kinsey" wrote in message
newsp.0d1jwqxqwdg98l@glass...
On Tue, 07 Jan 2020 20:35:23 -0000, Rod Speed
wrote:



"Commander Kinsey" wrote in message
newsp.0d1gkmz9wdg98l@glass...

Why secure a loft trapdoor in a storm?

And what's the roof pitch to do with anything?

In theory you can get a suction effect similar to
what you get with an aircraft aerofoil section.

In practice it isnt seen often enough to matter.

The conservatory I've half built is staying firmly put. I guess I bolted
it together well :-)

You can get flatish roofs lifted right off by strong
winds. basically due to the aerofoil effects.

"Close and secure loft trapdoors with bolts, particularly if roof pitch
is
less than 30°"

https://www.metoffice.gov.uk/weather...afe-in-a-storm