I would say that you should know where your studs are underneath, and try and walk there. There is give, and there is damage.
When I brought my /09 home I scrubbed and then polished the roof over the course of a few days, trying not to sit in the direct hot sun for too long. During that process, I took off every MaxAir vent, cleaned inside and out, and discovered some sources of leakage that I repaired.
I would certainly start on the outside with a thorough inspection, possible recaulking anything suspicious before going looking for trouble.
