Does a roof need felt?
Yes. Building code regulations require the use of 30lb. felt along the eave line for both shakes and shingles, plus 15lb felt for the underlayment with shakes. “I’ve heard that felt doesn’t allow the shakes or shingles to breathe, causing them to rot underneath. Is this true?” No. That is not the case at all. Inadequate ventilation in the attic is what causes the under side of a roof to sweat and eventually rot. A well ventilated attic will not only add many years to the roof, but it will also keep your home cooler in the summer. Most homes are too airtight. Good ventilation will make it more comfortable all year round.