I am stripping all asphalt shingles and felt paper from my roof. My sheathing is rough cut 1" x 8" pine. The roof is not a flat plane and therefore needs to be strapped with 2x4's and 2x6's and shimmed. It is a seasonal camp used only from June-October. My question is do I need felt paper on the sheathing to prevent condensation from leaking through the cracks. I understand this may occur with metal roofing.