At an eave end, where is the drip edge installed?

The drip edge should be installed under the felt when it comes to roofing installation. This is critical for ensuring that any water that runs off the roof is directed away from the underlying structure and does not seep underneath the roofing materials. By placing the drip edge under the felt, it creates a barrier that channels any moisture away from the wood sheathing or framing, which helps to prevent rot and water damage over time.

Installing the drip edge in this manner means that it not only acts as a protective feature but also helps in controlling the flow of water more effectively. Moreover, this installation technique maintains the integrity of the roofing system by ensuring that the felt paper and shingles can function as intended—namely, to keep water from penetrating into the roof structure.

Properly installing it under the felt also prevents issues like ice damming in colder climates, as the water is directed towards the outer edge of the roof rather than being allowed to pool where it could potentially cause damage.