We will be re-shingling our roof this weekend. I want to know if we have to put "tar paper" on all of the roof, or just near the edges. The interior is cathedral ceilings and I don't think there is much insulation. I think there are two layers of shingles. I don't want to have a flood this spring.
Answer:
To do it right, you can apply ice and water shield to the bottom edges of the roof and make it go up high enough to be at least 9" past the exterior wall. From there on up to the baffled ridge vent (the only way to ventilate a cathedral ceiling) you apply tarpaper under the shingles. This should be fun because both layers of the existing shingles must first be removed.
