Ah, you mean one of those strange ones that opens downwards? Mine lifts up, a much more sensible arrangement. It simply cannot open itself, it's too heavy.

On Tue, 07 Jan 2020 20:13:13 -0000, Brian Gaff (Sofa) wrote:

I don't know their reasons, but mine used to come open during high winds
dumping tons of old muck and dust onto my landing. Its now held shut with
duct tape. No nasty whining noises or rattles either. The roof on this
property is open ie it can bee seen there are gaps under the tiles, so one
assumes if that hole was through to the house and a really spectacular wind
came it could blow many tiles off the roof.
Brian