My sister is hoping to brighten up her kitchen/diner and there are a couple of these cracks, caused by people going up into the loft from time to time and a bit of stuff stored up there. There's no question of it being re-boarded or the rafters being strengthened. Is there a flexible filler available, that could tolerate a bit of movement? She would have to get someone in, so it would help if she knew a bit more about the options.
Cheers Andy C