Where Asphalt Starter Goes on a Roof

When installing asphalt shingles, the starter course is a critical foundation that ensures a durable, water-tight roof. The starter strip or starter course is a specialized row of shingles laid along the eaves and sometimes along the rake edge to establish a straight, uniform edge for the rest of the shingles. Proper placement improves wind resistance, reduces shingle blow-off, and helps seal the bottom row against moisture. This guide covers where asphalt starter goes on a roof, how to install it correctly, and common pitfalls to avoid for homeowners and roofers alike.

Understanding Asphalt Starter And Its Role

The starter course serves as the base for the entire shingle installation. It creates a level, straight edge, provides an initial sealant layer, and minimizes waste from sawn-off tabs at the bottom of standard shingles. There are two main types of asphalt starter materials: standard starter shingles (pre-cut, adhesive-backed) and cut- from-previous- or full-width shingles trimmed to a starter width. Either option, when installed correctly, helps form a secure first row that supports subsequent shingles and vents water away from the roof line.

Where To Start On The Roof

Edge Alignment And The Eaves

The primary location for asphalt starter is along the eaves, just above the drip edge, ensuring a straight, uniform lower edge for the entire roof. The starter row typically extends from one rake edge to the other, forming a continuous ledge that anchors the first row of shingles. When installed with standard starter shingles, the adhesive tab is oriented toward the roof interior, and the bottom edge should be flush with the drip edge to prevent water infiltration at the eave.

Rake Edges And Corner Considerations

For roofs with visible rake edges, special attention is needed to maintain a clean line at the corners. Starter material may be cut or formed to fit the rake edges, ensuring the first row remains straight and aligned. In some installations, a dedicated starter strip is used along the rake as well, especially on larger or steeper roofs. The goal is a consistent, square edge that helps all subsequent shingles sit properly and shed water efficiently.

Installing The Starter Strip With Shingles

Selection Of Starter Material

Select the appropriate starter material based on the shingle type and roof design. Pre-cut starter shingles are designed to match the width of standard shingles and often include a built-in adhesive strip. Alternatively, some installers prefer using a cut piece from a full-width shingle, trimmed to the correct width. Regardless of choice, ensure the starter aligns with the plan for the first row and creates a level reference line across the roof.

Preparation And Layout

Before installation, snap chalk lines along the eaves to mark the desired bottom edge of the starter row. Start at a corner and place the starter so the bottom edge aligns with the chalk line. If using a pre-cut starter, ensure the adhesive strip is facing up and toward the roof interior. The starter should cover the drip edge completely, with the bottom edge slightly overhanging the eave to shed water toward the soffit. Check for uniformity across the entire width of the roof before nailing.

Nailing And Attachment

Secure the starter according to the shingle manufacturer’s instructions. Nails are typically placed in the designated nail line on the starter, not through the adhesive. Common practice is to nail through the center of each tab or the marked nailing area, ensuring the fasteners are properly spaced to resist wind uplift. If using a full-width shingle cut to starter width, ensure the cut edge remains intact enough to grip the shingle above and create a solid lock for the next course.

Transition To The First Row Of Shingles

Once the starter is secure, begin laying the first row of shingles. Align each shingle with the edge of the starter so the bottom of the shingle sits above the starter line. The adhesive strip on each shingle should engage with the starter as designed, creating a tight seal as you progress. Maintain even exposure and consistent alignment along the entire eave to avoid stepped edges that can trap moisture or catch wind.

Common Mistakes And How To Avoid Them

• Skipping the Starter: Installing a full-width shingle without a proper starter can cause poor alignment and wind damage. Use the correct starter material to ensure a straight edge and proper seal.
• Improper Nailing: Nails placed outside the recommended zones weaken edges and jeopardize the seal. Follow the manufacturer’s nail patterns for the starter and subsequent rows.
• Misalignment At Eaves Or Rakes: Even slight deviations create visible seams and potential leaks. Use guides, chalk lines, and consistent spacing to maintain a straight line.
• Insufficient Overhang: Too little overhang at the eaves can trap water, while too much may compromise roofline aesthetics. Aim for the recommended overhang as specified by the shingle manufacturer.
• Inconsistent Wind Considerations: In high-wind areas, ensure starter and first-row nails are robust and placed per guidelines to resist uplift forces.

Tools, Materials, And Safety Considerations

Tools commonly used for installing asphalt starter include a utility knife, chalk line, measuring tape, straightedge, nail gun or hammer, roofing nails, and a pry bar for adjustments. Materials include the starter strip (pre-cut or cut from standard shingles) and the chosen roofing shingles. Safety gear such as a harness, non-slip footwear, and roof brackets or a stable ladder setup should always be used. For steep or high roofs, consider professional installation to reduce risk and ensure a durable, code-compliant result.

Maintenance And Long-Term Considerations

Properly installed starter shingles contribute to the roof’s long-term performance by supporting uniform shingle alignment and reliable water shedding. Over time, inspect the eaves for lifted edges, loose nails, or adhesive failure, especially after severe weather. If signs of damage appear, address them promptly to prevent moisture intrusion beneath the shingles. Regular maintenance extends roof life and helps preserve home value.

Visual Checks And Quick Reference

• The starter row runs along the eaves, with the bottom edge aligned to the drip edge and chalk line.
• The adhesive strip on starter shingles bonds with the first row of shingles for a secure seal.
• The transition from starter to first full row should be smooth, with consistent exposure and alignment.
• All nails follow the manufacturer’s recommendations for spacing and placement.