After having the roof replaced on my century old home, I have noticed that the plaster key has broken in many places on the ceilings of my second floor rooms due to the vibration from re-roofing. It has been suggested to me by co-workers that I need to install some 3/8 inch drywall panels on the existing plaster ceilings, tape and mud the joints and this will solve my problem. Is this the preferred solution? I thought about 1/2 or 5/8 inch firecode drywall on the ceilings, but I am very concerned about the extra weight put on the ceiling joists as they are only 2x4's on 2 foot centres spanning 11 feet.
Answer:
My first concern would deal witht he possibility of augmenting the integrity of the ceiling joists. If that cannot be done, I wouldn't dare put up even 3/8 drywall but if the joists can be firmed up, by all means, add 5/8 drywall as it makes the house that much more energy efficient.
