Starter Strips and Ridge Caps: The Edge Shingles That Keep a Roof On

Starter strips are the first row of shingle material at the eaves and rakes, laid under the first visible course, and hip and ridge caps are the pieces that close the hips and the peak. Both sit where wind gets under a roof first, and GAF’s shingle warranty ties its enhanced wind coverage to GAF starter strip products installed at the eaves and rakes.

Treat these parts as components of the wind and warranty system, not as trim; the roof components guide shows where they sit among the other layers. The questions to settle before you sign are which products the quote names for the edges and ridge, and what your shingle warranty requires there.

What the Starter Row Does at the Eaves and Rakes

The first visible course of shingles has gaps: the cutouts between tabs on three-tab shingles and the joints between neighboring shingles on every style. A starter row laid underneath fills those gaps so water that runs through them lands on shingle material instead of underlayment. It also puts a line of sealant along the roof edge, which bonds the first visible course down where wind pressure is strongest.

Wind explains why the edge matters. Air moving over the eaves and across the rakes pulls upward on the first course, and a shingle edge that is not sealed down gives that suction something to grab. Once the first course lifts, the next one is exposed from below.

The starter also has to sit in the right place relative to the drip edge. DOE’s Building America guide to asphalt shingle roofs says to “Install drip edge at eaves and rakes” and that “The starter strip should overhang ¼ to ¾ inches past the drip edge for drainage.” For a roof built to the IBHS FORTIFIED standard, the same page adds that “Starter strips and shingles must not extend more than ¼ in. beyond the drip edge.” Too little overhang and water can wick back toward the fascia; too much and the unsupported edge is easier for wind to lift. For the drip edge itself and its installation order, see drip edge at eaves and rakes.

Stricter programs ask for more at the edge. IBHS’s FORTIFIED Roof standard lists edge details “including a wider drip edge and a fully adhered starter strip.”

Why Cut 3-Tab Starters Are a Weak Substitute

Some crews make their own starter by cutting the tabs off three-tab shingles and laying the remaining strip along the edge. Others use full field shingles turned or trimmed. The result can look the same from the yard, which is exactly why you need to know what the quote names.

A purpose-made starter is built with its sealant line where the edge needs it. A cut or turned field shingle puts its sealant there only if the crew trims and orients each piece correctly, which is hard to confirm once the first course covers it. The firmest reason to insist on the named product, though, is the warranty consequence, because that one is written down.

That consequence is concrete on GAF roofs. The GAF Shingle & Accessory Limited Warranty (RESWT160L-0426), which applies to installations after January 1, 2025, defines its “Special Installation” for GAF shingles other than LayerLock-labeled ones as “use of 6 nails per shingle and GAF Starter Strip Products installed at the eaves and rakes.” A cut three-tab is not a GAF Starter Strip Product, so a roof built with one does not meet that condition.

Other brands set their own terms, which may differ, and any maker can revise its warranty form, so read the version that applies to your installation date.

Hip and Ridge Caps: The Last Course Wind Reaches

Hips and ridges are the roof’s high edges. Wind flowing over the house accelerates across them, and each cap piece is folded over the peak with both sides exposed. The nails that hold a cap are hidden under the next cap, so the whole run depends on each piece being bent cleanly, sealed to its neighbor and fastened where the next piece covers it.

Purpose-made hip and ridge products are made to be folded over that line. Caps cut from field shingles are another improvised option, and the same rule applies as at the eaves: if the warranty or the shingle maker’s instructions name a hip and ridge product, the quote should name it too.

On a roof with a ridge vent, the caps are nailed over the vent rather than directly over the deck. That changes the nail length needed to reach the deck, and the vent maker’s instructions add their own requirements, so ask which cap product and fastener the roofer will use over the vent.

Direction matters along a ridge, too. Each cap overlaps the next in one direction, so its exposed edge faces one end of the ridge; ask which way the crew will run the caps relative to the wind your house sees most in storms, since an edge that faces into that wind gives it something to catch.

From the ground, a cap line in good shape looks straight, lies flat and shows a consistent exposure from piece to piece. Lifted, cracked or missing caps after a storm call for a storm-damage check, which is a separate diagnosis from the product questions here.

What the Shingle Warranty Requires at the Edges

Start with what a warranty actually covers. Manufacturer warranties, as NRCA puts it in a consumer bulletin on roof system warranties, “provide only that the manufacturer will repair leaks that result from specific causes specified in the warranty.” Edge and ridge conditions sit inside that framework: they decide whether a given level of coverage applies at all.

GAF’s warranty shows how the conditions stack. Its enhanced wind coverage depends on the Special Installation described above, and for LayerLock-labeled shingles it accepts “4 nails per shingle” with “GAF Starter Strip Products installed at the eaves and rakes.” What the resulting wind coverage means, and how it relates to a shingle’s tested wind class, belongs to what wind classes mean. The nail-count side of the same condition is explained in nail count and placement.

When you read your own warranty, look for these items:

1. The list of qualifying accessory products, by name, for starter and hip and ridge.
2. The installation conditions for each level of coverage, including nail count and starter placement.
3. Whether coverage requires registration or a certified installer.
4. The covered causes of loss, and the exclusions.

Then compare the list to the quote. If the warranty names a starter and a hip and ridge product and the quote names neither, the quote does not yet describe a roof that qualifies. For how material, system and workmanship coverage differ, see material vs system warranties.

Checking Starter and Ridge Work in the Quote and Walkthrough

These checks happen before and during the job, and none of them requires you to climb.

In the quote, check for:

• A starter product named by maker and product line, at both eaves and rakes.
• A hip and ridge product named by maker and product line.
• Drip edge at eaves and rakes.
• The nail pattern the warranty requires, stated in writing.
• If there is a ridge vent, the vent product and the cap product that goes over it.

During the job, ask the crew to photograph the starter row along an eave and a rake while the first course is going on, so part of the starter is still exposed, with the product wrapper or label in one frame. That one photo answers the question no walkthrough can, because the starter disappears under the first course within minutes. In the photo, check two things: the starter sits at the edge with its sealant line along the eave or rake rather than up the slope, and its joints do not line up with the joints of the first course laid over it, so a seam never sits directly over a seam.

On a roof that is already finished, nobody can see the starter from the ground. The record is the invoice’s product list and any warranty registration, so ask the installer for both and keep them with your house papers.

At the walkthrough, look from the ground with binoculars for a straight eave line, shingles that overhang the drip edge by a small, even amount, and caps that lie flat along hips and ridge. For where these steps fall in the overall job, see the install sequence.

Should You Accept Field-Cut Starter or Ridge Pieces?

If your shingle warranty names the maker’s starter or hip and ridge products as a condition for coverage you want, do not accept field-cut pieces; ask for the named products in writing. If the warranty names no product and the maker’s installation instructions allow cut pieces, the choice is a workmanship one, and the roofer should state in the contract that the edge and ridge method follows those instructions.

Whichever case applies, the quote should name the starter and the hip and ridge products by maker; read the warranty’s edge conditions against it, and ask for a photo of the starter row before it is covered.

This guide is general information for U.S. homeowners, not legal, insurance, tax, or engineering advice. Codes, laws, and policy terms vary by location and change over time; confirm details with your local building department, your insurer, or a licensed professional.

Sources

• Asphalt Shingle Roofs, DOE Building America Solution Center
• FORTIFIED Roof, Insurance Institute for Business & Home Safety (IBHS)
• GAF Shingle & Accessory Limited Warranty (RESWT160L-0426), GAF
• Roof System Warranties (Consumer Advisory Bulletin Issue 1), National Roofing Contractors Association (NRCA)