Roof Crafters also removed and replaced two plywood boards that were rotten. They do a great job and a follow up on policing/picking up any nails and debris. They installed our new roof in 2016 and came back September 2020 for a Warranty issue, which was accomplished to our satisfaction. They are professional and I highly recommend them.
Yes, at Roof Crafters we will not install a new roof without removing the old felt as well as removing the old nails from the roof deck. We believe you can roof over rotten wood if you do not remove the old felt. One reason we remove the old nails is to minimize what is called nail pops. If you are getting a new roof you should demand that not only your old shingles be removed but the old felt and valley metal as well. If your roofing company is not doing this I would ask why not.
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