TL;DR: A starter strip is a factory-made asphalt product installed along the eaves and rakes of your roof before the first course of shingles. It seals the roof edge against wind uplift and water intrusion — two of the biggest threats to Florida roofs. Most major shingle manufacturers require it as a condition of their warranty, so skipping it can cost you coverage even if the shingles themselves are perfect.
If you’ve ever watched a roofing crew work, you may have noticed them laying a narrow strip of material along the very bottom edge of the roof before the first shingle ever goes down. That product has a name — a starter strip — and it quietly does some of the most important work on your entire roof.
Here’s what it is, how it works, and why no licensed Florida contractor should ever skip it.
What Is a Starter Strip?
Starter strip shingles are a pre-cut roofing product installed along the eaves and rakes before the first full course of shingles goes down. Their primary job is to fill the gaps between the tabs or edges of the first shingle course and the roof deck, sealing those joints with a factory-applied adhesive strip.
The reason this matters: a field shingle relies on the asphalt sealant strip on its underside to bond to the shingle below it. The first course at the eave has nothing below it except the underlayment. The starter strip solves that problem by giving the bottom edge of the first shingle course something solid and adhesive to bond to.
The finish shingles cover the starter strip completely, so the aesthetics of these starter shingles don’t matter — they’re usually covered with natural, darker roofing granules. You’ll never see it once the job is done, but it’s working every day.
How a Starter Strip Works
A starter strip performs three distinct jobs simultaneously: it seals joints, resists wind uplift, and creates a clean installation line.
1. It Covers the Joints in the First Shingle Course
At the eave, the starters provide a simple way to “cover” the joints between the finish shingles in the first course, ensuring complete water-shedding roof coverage.
Water can migrate up through the vertical joints at the eave through a process called capillary wicking, where surface tension pulls moisture horizontally behind the shingles — and left unchecked, that moisture leads to rot, mold, and decking failure. A starter strip cuts off that path before it starts.
2. It Bonds the Edge Against Wind Uplift
Starter shingles have a sealant strip, and when positioned correctly, it sits on the top surface at the lowest edge of the roof. At the rake edges, the starter doesn’t perform a joint-covering function, but it is integral in the roof’s overall wind resistance.
Without starter strips, strong winds could easily get up under the shingles on the edges of your roof. In Central Florida and the Space Coast — where tropical systems can drive sustained winds well above 100 mph — that vulnerability is not theoretical. It’s a recurring source of insurance claims.
3. It Creates a Consistent, Straight Edge
The advanced adhesive on the starter is precisely placed to help keep the shingles in place, and because starter strip shingles are manufactured in a controlled environment, they are uniform and result in an aesthetically pleasing finished roof edge.
Where Does the Starter Strip Go?
Starter strips are installed along the eave edge first, then along the rake edges on both sides of the roof. The eave installation runs horizontally across the bottom, while rake starter strips run vertically up the sloped edge, providing coverage at every exposed perimeter where wind and water pressure are highest.
The Florida Building Code’s shingle installation section specifies that the starter strip shall be a row of either self-sealing nonlaminated shingles or approved starter shingles. At every intersection — eaves, rakes, and gable ends — shingles and starter strips shall be set in a minimum 8-inch-wide strip of approved flashing cement.
The starter strip also works closely with your drip edge. If you want to understand exactly how those two components interact at the roof perimeter, see our explainer on what is a drip edge and why every Florida roof needs one.
Why Skipping It Can Void Your Shingle Warranty
This is the part most homeowners don’t find out until it’s too late.
Starter strips are recommended with virtually all asphalt shingles, both three-tab and architectural styles. Most major shingle manufacturers require a compatible starter product for the full warranty to remain valid, so skipping this step can leave homeowners without coverage even if the shingles themselves are in good shape.
Here’s what that means in practice across the three brands Thomas Roofing works with most:
- GAF: To qualify for GAF’s WindProven Limited Wind Warranty, you must install GAF LayerLock-labeled shingles and at least four qualifying GAF accessory products, including GAF Ridge Cap Shingles, GAF Starter Strip Shingles, and a GAF Roof Deck Protection product.
- Owens Corning: The 160 MPH wind rating is applicable when Owens Corning component requirements are met and with starter shingles installed on both the eaves and rakes.
- IKO: The Limited High Wind Resistance Warranty will only apply if IKO starter strip shingles have been installed at eaves and rakes.
For a shingle system to qualify for its Class H wind rating, the manufacturer requires the matched starter product. A GAF Timberline HDZ installed with a generic starter strip is only rated to Class G — even though the shingle itself can achieve Class H. That difference in rating matters enormously in hurricane country.
Purpose-Made Starter Strip vs. Cut Three-Tab Shingles
Some contractors — especially those cutting corners on price — will flip a standard three-tab shingle upside down and use it as an improvised starter. It saves them $100–$300 in material. It can cost you your warranty.
Some roofing contractors may think that cutting three-tab shingles will work as a roofing system’s starter strip, but that could risk the adhesive being improperly placed without a tight seal.
For years, some roofers improvised starter courses by flipping a standard three-tab shingle upside down and trimming off the tabs. It worked to a degree, but it left the sealant strip in the wrong position and created inconsistent coverage across the eave. Purpose-made starter strips solve both problems.
Some contractors skip starters to save cost — roughly $100–$300 on material. This is a red flag. Demand starter shingles or go with another contractor. It’s a basic requirement, not an upgrade.
Why This Matters Even More in Florida
Florida’s climate creates a convergence of threats that make every layer of roof protection count more here than in most other states.
- Hurricane wind uplift: Eaves and rakes are the first points where wind gets under a roof. The eaves and rake edges of your roof are the parts most vulnerable to the elements. A properly bonded starter strip is the first line of defense.
- Tropical rainfall: Florida’s intense, wind-driven rain forces water horizontally against roof edges in ways that gravity-only drainage designs never anticipate. Joint sealing at the eave is critical.
- Coastal salt air: For Space Coast and Volusia County homeowners, salt-laden air accelerates the degradation of any weak point — including an improperly sealed edge.
- UV and heat: The Florida sun activates the thermal adhesive on the starter strip, bonding it firmly to the shingle above. The sealant strip is activated by sunlight and plays a vital role in forming a strong bond with the regular shingles above. That bond has to form correctly, which requires a purpose-made product with adhesive in the right location.
The Florida Building Code — one of the most stringent in the country — requires asphalt shingles to meet ASTM D3161, ASTM D7158, or TAS 107 test standards to determine wind uplift classifications. The starter strip is part of the tested system that achieves those ratings. Remove it, and the assembly’s tested performance is no longer valid.
The starter strip also works in coordination with your roofing underlayment beneath it. For a full breakdown of how those layers interact, read our guide on what is roofing underlayment and why it matters in Florida’s climate.
How Long Does a Starter Strip Last?
A properly installed starter strip typically lasts as long as the shingles above it — anywhere from 25 to 50 years depending on the shingle product and maintenance of the overall roof system. Because it is sandwiched between the shingle and the decking, it is protected from direct UV exposure and physical wear.
In short: it goes in once and never has to be thought about again — provided it was installed correctly in the first place.
How to Confirm Your Contractor Is Using One
Before your roof replacement begins, ask your contractor these direct questions:
- Are you using a manufacturer-approved starter strip at both the eaves and rakes? Both locations matter.
- Is the starter strip the same brand as my shingles? Mixing brands can disqualify you from system-level warranties.
- Can I see the product label on the starter strip bundle? A reputable contractor won’t hesitate to show you.
- Will the warranty documentation reflect the full system installation? This is especially important for enhanced warranties like GAF’s System Plus or Owens Corning’s Platinum Protection.
At Thomas Roofing and Repair, every shingle installation uses manufacturer-matched starter strips at both eaves and rakes — installed to current Florida Building Code and manufacturer specifications. As a CertainTeed ShingleMaster Pro and Owens Corning Preferred Contractor, we install complete roofing systems, not just shingles, so our customers qualify for the strongest available warranties from day one. Our work is also backed by the Blue Shield Loyalty Program, which includes a 7-year workmanship warranty, free annual inspections, and priority scheduling after named storms.
Have questions about your existing roof or an upcoming replacement? Contact our team at any of our three offices — Orlando, Holly Hill, or Titusville — for a no-obligation inspection. Spanish-speaking staff are available at all locations.
Recommended Reads
- What Is a Drip Edge and Why Does Every Florida Roof Need One?
- What Is Roofing Underlayment and Why It Matters in Florida’s Climate
- What Is Roof Fascia — And What Happens When It Fails?