Flat roof rafters noise
We have just closed on the house that was build in 1961 and planning on doing a complete remodeling.
There seems to be an issue with a flat roof framing as we hear a very load popping noise in the ceiling most of the time we are in that house (we currently don't live there). Noise seems to be more in the mornings and less during the day and there is absolutely no noise in the overcast and rainy days which tells me that this noise has something to do with sun hitting the roof and some kind of expansion.
Roof seems to have 2 layers and it looks like 2nd layer was not installed properly so I would to do the re-roofing as part of remodeling.
What I wanted to ask if what could be the nature of this noise? What steps do I need to take to trouble shoot this issue?
Also, it sounds like this noise does travel from one side of the house to another. Other words it can pop in the living room and then continue popping all to the to the end of the house. Currently our ceiling is open so I can see 1 x 6. It looks like above them I have a 6 inches of roof sheathing which could be 2 x 6 and then on the roof itself I have 1 x 6 again (no plywood) on which the roofing material is residing.