In our previous house, in Andover, on several occasions we opened the upstairs windows to find hundreds of flies sheltering in the gap. It was a horror film as the black buzzing horde invaded the bedroom.
Here in Wells we've had a mini rerun. To escape the endless rain, wind and cold the vile flies have been creeping into the exhaust vents of the bathrooms. After a few hours, four or five have made it all the way past the fan and are buzzing around the wash basin and toilet. Yeuk!
I have taken to spraying insecticide into the fan.
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Just installed Google Drive, which looks a lot like DropBox.