This job was done in St Helens Tasmania, on a 150 year old house. The room here was full of what we call crazy cracks through out the whole ceiling. It was not an option to re-sheet the ceiling as the owner wanted to keep the heritage style of the building, which is fair enough as it is a very old residence.
What we did here was to dig out any cracks that were big enough to do so, the small hairlines do not need this. Then once dug out we trowelled them back up with cornice cement to set hard again.
After the dug out cracks were set hard again all the cracks were then taped with a fibreglass joint taped called FibaFuse. The cracks were then given another coat of base and then a final coat of topping to allow for sanding.
As you can see the entire ceiling was nearly trowelled, as myself and the owner had a few jokes about, but this is what was needed to be done to maintain this lovely 150 year old buildings heritage. #ceilingcracks
Regards
Phil
Phil The Cracks Plastering LAUNCESTON 
Repairing cracks In a 150-year-old house by keeping the original material must be done by a professional plasterer. The plastering advice in this post is good and self-explaining, it will help the novice to try and plaster his own home. Phill your plastering tips are great and easy to follow I also have the how to for plastering.
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