Would have to agree with Shaun on this one. Nothing is a better insulator than a compartmentalised air space, and the aluminium foil option is very light, and will reflect and dissipate radiant heat well. The problem with ceramic blanket is that it might be slow to heat up but once it is hot it will also retain heat for longer than Shaun's option.

Just one other thing.....the softening point of epoxy resin is around 100 degrees C depending on the type of resin of course. I would not want my fuselage getting that hot as permanent deformation can result. If I can feel the fuse is warm I would fix the problem rather than tempt fate.

Hope that helps.