Currently there is just 20mm of fiberglass insulation. So my question is can I “just” cut a 6 inch hole at the top of the ceiling and fill the cavity with a loose insulation.?
I’ve had a survey from one of the energy companies and they said “your cavity is too small for wall insulation and we don’t do your type of roof, bye”…. (I’m so glad I took a day off work for that

Any help or ideas to try to reduce my heating costs would help.
Thanks
Dave,