My workshop is a converted barn with corrugated fibre cement sheeting roof.
It's been sprayed with expanding foam and when they did it they assured me
that they'd sealed the apex where there is a 'top hat' shape.

Well they obviously didn't - I recently had an enormous bonfire ( 1/2 mile
of Leydandii hedge top and there is a line of 'fall out' ash down the
length of the workshop. So if the ash blew in then my heat MUST be able to
go out !

No chance of getting them back, as access is now very difficult with all the
machines in place, and I don't want them covered in foam anyway !

SO - my thought was some form of insulating sausage that I can poke up there
with a long stick - if there was such a thing as a 6" diameter cylindrical
shape I reckon it would stay in place by friction.

??? BUT YOU MAY HAVE OTHER SUGGESTIONS PERHAPS ???


Andrew