Moisture above roof sheathing
We just removed some very old insulation from between the rafters of our attic ceiling. Between the sheathing boards there is moisture (beads of water) on the underside of the tar paper (see photo). The board shows signs of moisture damage. In other cracks in the sheathing, the tar paper is completely dry. It was 30-32F at the time, attic is unheated (but obviously slightly warmer than outside temp). This morning there was frost on the roof.
What is the most likely cause of this? The roof was last replaced in 1997. I’m also attaching photos of the outside of the roof, and another crack between roof sheathing boards where tar has oozed in- not sure of the significance (if any) of that! Time to replace the roof? Should the sheathing be replaced too? Many thanks for this very helpful site.
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