Roof drip edge is a corrosion-resistant metal flashing bent into an L, T, or extended profile that runs along the eaves and rakes of a roof. It carries runoff past the fascia and into the gutter instead of behind it, and it is required by the International Residential Code (IRC R905.2.8.5) at eaves and rake edges of asphalt shingle roofs.
The part is small and cheap, yet skipping it or lapping it in the wrong order is one of the more common causes of rotted fascia and sheathing along a roof edge. This guide covers what drip edge is, the standard profile types, materials and gauges, where each piece goes, and the exact code spec, so you can spec it or check an installer’s work.
Last reviewed: September 2026. By The Roofing Brief Team.
What a drip edge does
A drip edge is metal flashing installed along the perimeter of a roof, at the horizontal eaves and the sloped rake edges. Water clinging to the underside of a shingle tends to wick backward toward the deck by surface tension. The drip edge gives that water a lower lip to break off from, so it drops clear of the fascia board and the wood beneath the roofing rather than running behind the gutter.
Alongside directing water, it stiffens and supports the shingle overhang at the edge, which helps limit curling and wind lift at the most exposed part of the roof. For the specific question of directing water into a gutter versus over the edge, see our companion piece on drip edge versus gutter apron. You can also locate the eaves, rakes, and fascia on our labeled roofing terminology diagram.
Drip edge profile types
Manufacturers and the industry loosely classify drip edge by letter, based on the bent profile. The letters are a shorthand for shape, not a strict standard, so a supplier may label the same piece differently. The three you will encounter most are Type C, Type D, and Type F.
| Type | Profile | Common use | Notes |
|---|---|---|---|
| Type C (L-style) | Simple 90-degree L bend with a lower flange | Eaves and rakes, often on lower-slope and metal roofs | The simplest and usually the least expensive profile |
| Type D (T-style) | T-shaped with the leading edge kicked out away from the fascia, plus a hemmed bottom | Eaves, where you want water thrown farther from the wall | The Asphalt Roofing Manufacturers Association (ARMA) prefers a T profile |
| Type F (gutter apron) | Extended leading edge with a longer face | Retrofits over existing shingles, or to reach out over molding and drop water into a gutter | The long lip helps it clear trim and feed a gutter |
Thinner stock is often finished with a hemmed edge, where the metal is folded back on itself along the bottom lip. The fold adds rigidity to a light-gauge piece so it holds a straight line along a long run.
Materials and gauge
Drip edge is sold in several metals. Aluminum is the most common residential choice for its corrosion resistance and low cost, with galvanized and stainless steel used where more strength is wanted, and copper on higher-end or historic work. Whatever the metal, code requires it to be corrosion resistant.
| Material | Typical thickness | Where it fits |
|---|---|---|
| Aluminum | About 0.019 in (some lighter 0.015 in stock exists) | Most residential shingle roofs |
| Galvanized steel | About 0.019 in (26 gauge) up to 0.024 in (24 gauge) | When more rigidity or impact resistance is wanted |
| Copper / stainless | Varies by supplier | Premium, historic, or coastal work |
Pieces commonly ship in roughly 10-foot lengths. As a rough cost signal, home-service estimates often put basic Type C aluminum in the range of a few dollars per 10-foot piece, with heavier steel and copper costing more; local pricing varies, so treat any single figure as an anchor rather than a quote.
Where each piece goes: eaves versus rakes
Drip edge runs along two different edges, and the sequencing differs between them, which trips up a lot of installs.
- Eaves are the lower horizontal edges where the gutter usually hangs. Here the drip edge goes on first, directly on the deck, and the underlayment laps over the top flange of the drip edge.
- Rakes are the sloped edges running up to the ridge. Here the order flips: the underlayment goes down first, and the drip edge is installed over the underlayment.
The logic follows the water. At the eave, any water on top of the underlayment should run out over the metal and off the roof. At the rake, water shedding down the slope should stay on top of the metal.
What the code requires
For asphalt shingle roofs, IRC Section R905.2.8.5 sets the baseline. The commonly cited requirements are:
- A drip edge is required at eaves and rake edges of shingle roofs.
- The metal must be corrosion resistant.
- Adjacent lengths overlap not less than 2 inches.
- The flange extends up the roof deck not less than 2 inches.
- The edge extends not less than 1/4 inch below the roof sheathing.
- It is mechanically fastened to the deck at not more than 12 inches on center.
Fasteners follow the roofing-nail spec referenced in R905.2.5, generally corrosion-resistant roofing nails with a minimum 12-gauge shank and a 3/8-inch-diameter head. Codes are adopted and amended locally, so the edition your jurisdiction enforces may differ; confirm with your local building department before relying on any single number here.
Installation order, step by step
On a standard asphalt shingle roof, the typical sequence is:
- Install drip edge along the eaves first, fastened to the deck.
- Run the underlayment (or ice-and-water membrane at the eave, where used) over the eave drip edge.
- Install drip edge along the rakes, this time over the underlayment.
- Overlap each new length of drip edge over the last by at least 2 inches, working so upper pieces shed onto lower ones.
- Install shingles, keeping the starter course aligned to the drip edge so the edge is supported.
Common mistakes
- Reversing the eave sequence. Tucking the underlayment beneath the eave drip edge lets edge water run behind the metal and onto the fascia.
- Skipping it on a re-roof. Older roofs sometimes have none; a tear-off is the moment to add it. A Type F gutter apron can sometimes be slipped in on an existing edge, but a full install is more reliable.
- Under-lapping the seams. Butt joints or short overlaps open a path for water at every seam.
- Wrong relationship to the gutter. If the edge is too short or set behind the gutter’s back, water can run behind the gutter instead of into it. See why water runs behind a gutter for the failure modes.
Frequently asked questions
Is drip edge required by code?
For asphalt shingle roofs, yes. IRC R905.2.8.5 requires a drip edge at both eaves and rake edges. Local amendments and other roof coverings can change what applies, so confirm with your building department.
What is the difference between a drip edge and a gutter apron?
A gutter apron is a specific drip edge profile (often called Type F) with an extended leading edge designed to reach over trim and drop water directly into the gutter. All gutter aprons are a form of drip edge, but not every drip edge is shaped to feed a gutter. Our drip edge versus gutter apron guide compares them directly.
Does the underlayment go over or under the drip edge?
It depends on the edge. At the eaves the underlayment goes over the drip edge. At the rakes the drip edge goes over the underlayment.
What size and gauge of drip edge should I use?
Residential aluminum drip edge is commonly around 0.019 inch, with galvanized steel running from about 26 gauge (0.019 inch) up to 24 gauge (0.024 inch) for more rigidity. The right size also depends on the fascia and gutter it has to reach; match the profile to the edge condition.
Can you add drip edge to an existing roof?
A gutter-apron style piece can sometimes be worked in along an existing eave, but installing full drip edge is best done during a re-roof when the shingle edge is open. The eaves-first, rakes-over sequencing is hard to correct once shingles are down.