I have stripped most of the attic (was an unregistered conversion) and the rafters have what seems to be additional timber on them which aligned with the previous wall/roof covering. The timbers impede the straight runs of about 400mm wide by cutting in at the top and bottom but some cut the 400mm wide 'channels' in half and I worry about how much insulation I will lose across the roof span.
Question is, what is my best option, to remove or insulate around? Will be using celotex PIR or similar. I have removed a handful of the 'additional' timber and wasn't concerned until I met 1st fix nails.
