The Practice Management Knowledge Community (PMKC) identifies and develops information on the business of architecture for use by the profession to maintain and improve the quality of the professional and business environment. The PMKC initiates programs, provides content and serves as a resource to other knowledge communities, and acts as experts on AIA Institute programs and policies that pertain to a wide variety of business practices and trends.
Thanks for your response. I think you are correct about the cause of the problem.
Now I am trying to fined out what the original roof deck was made of.