The decision to install new shingles involves selecting materials, planning the layout, and following safe, code-compliant practices. This guide outlines practical steps, best practices, and common mistakes to help property owners understand the process and make informed choices when putting shingles on a roof.
Assessing The Roof And Planning
Before starting, inspect the roof for structural integrity, damage, and ventilation. A sturdy deck, proper attic airflow, and sufficient insulation reduce long-term problems. Check local building codes and obtain any required permits. Measure the roof area to estimate material quantities and waste. Create a replacement plan that accounts for weather windows, as mild, dry days minimize moisture exposure.
Choosing Shingle Type And Underlayment
Most residential roofs in the United States use asphalt shingles for cost and durability. Architectural shingles offer enhanced curb appeal and longer life than three-tab shingles. For unusual climates, consider silicone or rubberized underlayment in high-wind areas. Underlayment protects the deck from moisture and ice damming, acting as a secondary barrier when shingles fail. Select underlayment rated for your climate and ensure it overlaps correctly with flashing and edge details.
Tools, Materials, And Safety Gear
Keep a well-organized workspace and use the right gear for safety and efficiency. Tools include a pry bar, hammer, utility knife, chalk line, straightedge, tin snips, roofing nail gun or hammer, roofing nails, ladders, fall-arrest gear, and a roof harness. Materials consist of starter strips, shingles, underlayment, leak barriers around valleys and penetrations, flashing, ridge and hip cap shingles, and vent boots. Safety gear should include gloves, eye protection, non-slip footwear, and a hard hat. Have a buddy or team for handling heavy loads and raising bundles.
Removing Or Preparing The Existing Roof
If removing old shingles, start at the lowest course and work upward. Score and lift shingles with a utility knife or pry bar, then detach them from the deck. Inspect the roof deck for rot, mold, or loose boards and replace damaged sections. If the old roof is in good shape, you can install over existing shingles in some cases, but many codes require removal when shingles are damaged beyond a certain extent. Ensure the deck is dry, flat, and free of protrusions before applying new underlayment.
Installing The Underlayment And Starter Strips
Roll out the underlayment over the roof deck, aligning with the eaves and rakes. Attach with corrosion-resistant nails or staples at prescribed intervals, ensuring the underlayment lies flat without wrinkles. Install a starter strip along the lower edge of each slope to provide a clean, uniform edge and to help prevent water infiltration at the first row of shingles. The starter strip minimizes shingle lift in high winds and improves overall roof performance.
Laying The Shingles In Courses
Begin with the first full row of shingles on the lower edge, aligning with the starter strip. Use a chalk line to maintain straight, even courses. For each row, stagger seams at least 6 inches from the row below to reduce water intrusion. Nail placement is critical: drive nails just above the shingle tab line and through the strong part of the shingle, following the manufacturer’s nail pattern. Do not overtighten nails, which can crack shingles or cause buckling.
Flashing, Valleys, And Ventilations
Install flashing at roof valleys, chimneys, skylights, and along edges to divert water away from joints. Use leak barriers under flashing for extra protection in wet areas. Valley flashing should be installed with a proper overlap to channel water downward. Ensure roof vents and under-eave soffit vents maintain adequate attic ventilation to prevent condensation and heat buildup, reducing shingle deterioration. Sealing around penetrations with compatible sealant helps prevent leaks.
Ridge, Hip Caps, And Finishing Touches
After completing the main field, install ridge and hip caps to seal the roof edges and create a finished look. Cut caps to fit irregular angles and ensure consistent overhangs. Inspect the entire roof for loose shingles, nail heads that protrude, or gaps. If wind-driven rain is a risk, consider applying a roof sealant or additional leak barriers in vulnerable areas. Clean up debris, store leftover materials, and dispose of old shingles following local waste guidelines.
Maintenance, Inspection, And Longevity
Regular inspections after severe weather help catch issues early. Look for lifted shingles, damaged flashing, or granule loss in gutters. Clean debris from gutters and inspect attic insulation for moisture intrusion. Most asphalt shingles offer 20 to 30 years of life with proper maintenance, depending on climate, installation quality, and exposure to wind and sun. Address minor repairs promptly to extend roof life and protect interior spaces.
Common Mistakes To Avoid
- Skipping underlayment or improper overlap, which raises leak risk.
- Incorrect nail spacing or nailing through the shingle surface, causing damage.
- Failing to remove debris or to check for deck repairs before installation.
- Inadequate attic ventilation, leading to moisture buildup and shingle deterioration.
- Improper starter strip and flashing installation around penetrations, valleys, and edges.
Cost Considerations And DIY Readiness
Roofing costs depend on materials, labor, local permitting, and roof complexity. Asphalt shingles tend to be cost-effective, while architectural shingles increase upfront costs but may offer longer life and better appearance. DIY installation can save labor costs but requires skill, time, and safety discipline. For most homeowners, professional installation ensures correct flashing, ventilation, and warranty compliance. Always obtain quotes from licensed contractors and verify insurance and references.
When To Hire A Roofing Professional
Consider professional help if the roof shows widespread damage, if you lack safe access to the roof, or if local codes require professional installation for warranty coverage. Signs that call for expert service include persistent leaks, significant deck rot, or complex roof geometry. A licensed roofer can assess structural integrity, provide a detailed estimate, and ensure proper flashing, insulation, and ventilation are in place.
Environmental And Practical Considerations
Choose shingles with recycled content or those that can be recycled at end of life to reduce waste. Proper disposal of old shingles helps minimize environmental impact. Plan for appropriate venting and insulation to optimize energy efficiency and indoor comfort. Consider reflective or cool roofing options if high summer heat is a concern in your region.