Tech Shield Roofing

At Tech Shield Roofing, we specialize in protecting your home with high-quality roofing and siding services you can trust.

Free Inspections
Roof Repairs & Full Replacements
Siding Installation & Repairs
Leak, Chimney & Flashing Specialists
Fully Insured

Whether your home has damage or you’re planning an upgrade, we’re here to get it done right the first time.

Call today for a FREE estimate: 774-517-6989

Proper Drip Edge and Underlayment Installation

This technical illustration demonstrates the correct layering sequence for installing roof drip edges and underlayment (roof felt) at the intersection of an eave and a rake. The primary goal of this specific arrangement is to manage water runoff effectively, ensuring that moisture is directed away from the wooden roof deck and fascia to prevent rot and water damage.

Key Components

Eave Drip Edge: Installed first, this metal flashing sits directly on the OSB roof deck and tucked under the roof felt to protect the lower edge of the roof (the eave).

Roof Felt (Underlayment): Applied after the eave drip edge, this moisture barrier covers the OSB. It laps over the eave metal but stays under the rake metal.

Rake Drip Edge: Installed along the sloping edge of the roof. Critically, it is placed on top of the roof felt to prevent wind-driven rain from getting under the underlayment.

OSB on Roof: The structural sheathing (Oriented Strand Board) that serves as the base for the roofing assembly.

Facia & Barge Rafter: The vertical finishing boards that the drip edges protect from water dripping off the roof surface.

Fasteners: Specified as 7/8" roofing nails spaced on 24" centers along the top edge of the flashing.

System Overview

The image provides a clear "best practice" guide for roofing transitions. The logic follows the path of water: at the bottom (eave), the felt goes over the metal so water sheds onto the metal and then into a gutter or off the roof. On the sides (rake), the metal goes over the felt so that water running down the slope cannot seep under the edge of the felt. The note emphasizes that in a real-world application, the rake metal should be trimmed to overlap the eave metal seamlessly at the corner to eliminate gaps.