Drip edge calculator

Add up the length of all eaves and rakes — roughly the roof perimeter, or 2 × (length + width) for a simple roof — and add about 10% for overlaps and corner cuts. Enter your roof size above for the linear feet and piece count.

Standard pieces are 10 feet (often labeled 10 ft 6 in — the extra few inches allow for overlap at each joint). The calculator divides your total linear feet by 10 to count pieces and rounds up.

At the eaves it goes under the underlayment; along the rakes it goes on top of it. Most building codes now require drip edge on both.

Overlap each joint about 1–2 inches. The built-in 10% waste allowance covers those overlaps plus corner cuts; bump it up for a cut-up roof with lots of edges.

The three common profiles are Type C (an L-shaped bend, the simplest), Type D (a “T” profile with a lower kick-out that throws water clear of the fascia — often required by code), and Type F (a longer top flange, used over existing shingles or on rake edges). Type D is the most widely specified for new roofs; check your local code and match the flange size to your shingle overhang.

Aluminum drip edge runs about $2–$5 per 10-foot piece, or roughly $0.25–$0.50 per linear foot; galvanized steel and heavier gauges cost a bit more. A typical single-story house needs about 150–250 linear feet, so material is usually well under $150. Multiply the linear feet from the calculator by your local price per foot.

Retrofitting drip edge under shingles that are already down runs about $1–$3 per linear foot installed, so a typical 150–250 linear foot house lands around $150–$750 — and many roofers charge a $150–$300 minimum for a small standalone job. It costs more than drip edge on a new roof because each shingle edge must be gently lifted (and the first course sometimes re-nailed) to slip the flange underneath. Rake edges are easier: a Type F profile is made to slide over existing shingles, which is why retrofits often use it.

It depends on the roof footprint, not the living area. A single-story 2,000 sq ft home is roughly 40 × 50 ft — about 180 linear feet of edge, or 20 standard 10-foot pieces with waste. A two-story 2,000 sq ft house has a smaller footprint (~1,000 sq ft), so it needs closer to 14 pieces. Enter your roof’s length and width above for your exact count.

Both are edge flashing, but the lower leg is shaped differently. Standard drip edge (Type C or D) has a short kick-out that throws water off the fascia; a gutter apron (a Type F profile) has a longer, angled lower leg that reaches over the back of the gutter so water can’t wick behind it. Use a gutter apron along eaves that have gutters and regular drip edge along the rakes. If your fascia is staining or water runs behind the gutter, a gutter apron is usually the fix — count it in the same linear feet the calculator gives for your eaves.