A roof drip edge is the formed metal flashing along the eaves and rakes that steers runoff off the roof edge and away from the fascia and sheathing. King Roof Care handles roof repair, replacement and inspection in Kirkland, Bothell, Everett, Issaquah and Redmond, WA. Drip edge is not listed as a separate service, so ask about it when you request an estimate.
What a Roof Drip Edge Does on a Pitched Roof
A roof drip edge is a strip of formed metal installed along the roof perimeter, at the eaves and usually along the rakes. Its job is to let runoff drip clear of the roof edge instead of curling back under the shingles.
- Moves runoff past the fascia instead of along it
- Covers the vulnerable edge of the roof decking
- Gives the first shingle course a stiff, straight edge
- Helps guide water into the gutter rather than behind it
Types of Roof Drip Edge: L-Shaped, T-Shaped, C-Shaped and Gutter Apron
Roof drip edge comes in a handful of standard profiles. The right one depends on the shape of the roof edge, the depth of the fascia and where the gutter hangs.
| Profile | Common name | Shape | Typical use | Trade-off |
|---|---|---|---|---|
| L-shaped | Type C | A simple right-angle bend | Rakes and eaves where water only needs to clear the fascia | Small kick-out, so water runs closer to the fascia |
| T-shaped | Type D | Deck flange, vertical face and an outward drip lip | Eaves above gutters on pitched shingle roofs | Extra lip pushes water farther out; more visible from the ground |
| C-shaped | Hemmed or wrap edge | Wraps around the edge of the decking | Edges where the sheathing edge needs full cover | Must match the decking thickness to fit snugly |
| F-shaped | Gutter apron | Longer face with a lip that tucks behind the gutter | Eaves where the gutter back sits under the flashing | Only useful where gutters are present |
Roof Drip Edge Sizes, Widths and Lengths
Roof drip edge sizes are described by several measurements. These are the width of the flange that lies on the deck, the depth of the face that hangs over the fascia, the length of each piece and the thickness of the metal.
- Deck flange width: how far the metal reaches onto the roof
- Face depth: how far it covers the fascia
- Drip lip: whether there is an outward kick at the bottom
- Metal thickness: how well it holds a straight line in wind
Metal Roof Drip Edge and Drip Edge Material Choices
Metal roof drip edge works differently from drip edge on a shingle roof. Panel and standing-seam roofs usually finish with eave trim and rake trim that the panels hook onto or close over.
| Material | Strengths | Watch-outs |
|---|---|---|
| Aluminum | Light, resists rust, many color options | Dents more easily; keep it out of direct contact with copper |
| Galvanized steel | Stiff, holds a straight edge | Coating can wear at cuts and scratches, which can lead to rust |
| Painted or coated steel | Can be color-matched to trim or metal panels | Scratches from handling should be touched up |
| Copper | Long-lasting look that develops a patina | Higher material cost; must not touch aluminum or galvanized steel |
| Vinyl | Lower material cost, does not corrode | Less rigid and can turn brittle; limited use on roof edges |
How a Roof Drip Edge Is Installed, Step by Step
Roof drip edge installation follows a set order relative to the underlayment. Getting that order wrong can send water behind the flashing instead of over it.
- Inspect the fascia and the edge of the decking, and replace rotted wood before any metal goes on.
- At the eaves, fasten the drip edge to the deck. Lay ice-and-water protection and underlayment over its flange, so water on the underlayment drains onto the metal.
- At the rakes, lay the underlayment first and the drip edge on top, so wind-driven rain on the gable stays above the membrane.
- Lap each joint in the direction water flows, and nail through the flange into the deck, not through the face.
- Where an eave meets a rake, trim the corner so the rake piece overlaps the eave piece.
- Set the starter course and shingles so they overhang the drip edge slightly, letting water leave the shingle onto the metal lip.
- Check that the gutter sits where the drip edge or gutter apron empties into it.
King Roof Care Replacement Scope and Drip Edge Repair
King Roof Care's roof replacement scope covers the parts of the roof around the drip edge:
- Tear-off and haul-away of the existing roofing material
- Inspection of the roof deck, with damaged sheathing replaced as needed
- New underlayment, plus ice-and-water protection where the roof requires it
- Flashing at valleys, walls, chimneys and other roof penetrations
- Starter course, ridge caps and a full cleanup
Signs of Roof Drip Edge Problems and Mistakes That Cause Rework
Roof drip edge problems tend to show up first along the eaves and gable ends. Look along the roof edge from the ground before anyone climbs a ladder.
- Sign: streaks, stains or peeling paint on the fascia
- Sign: soft or darkened wood near the gutter line
- Sign: water running behind the gutter instead of into it
- Sign: bent, loose or lifted metal after a windstorm
- Sign: rust spots or gaps between the metal and the fascia
- Mistake: underlayment tucked under the eave drip edge instead of over it
- Mistake: reusing bent or corroded edge metal
- Mistake: mixing incompatible metals or fasteners
- Mistake: nailing through the face or leaving joints lapped against the flow of water
- Mistake: relying on sealant instead of correct laps and overlaps
What to Ask in a Roof Drip Edge Estimate
Roof drip edge cost depends on several things. These include the total length of eaves and rakes, the profile and metal chosen, and whether shingles or gutters must be removed to reach the edge.
- Which profile goes on the eaves and which on the rakes?
- Which metal, thickness and color is specified?
- Is the drip edge being replaced, or is existing metal being reused?
- Will the eave metal sit under the underlayment and the rake metal over it?
- How will rotted fascia or edge sheathing be handled if it is found?
- How are joints and corners lapped and fastened?
- Do the gutters need to come down and be rehung?
- Is the drip edge listed as its own line item?
Getting a Roof Drip Edge Checked with King Roof Care
King Roof Care, based at 16007 NE 6th St in Bellevue, WA, provides roof repair, roof replacement, roof inspection, storm damage repair and gutter work across its service area.