The Roof Replacement Process, Step by Step

A roof replacement involves a precise sequence of steps that determine how the finished system performs over the next 25 to 50 years. Understanding the roof replacement process removes the uncertainty and lets you know exactly what to expect on installation day.

This guide walks through each phase in order, from pre-project planning through the final walkthrough, with the specific durations and methods used on West Hartford residential projects. For a breakdown of how project length varies by home size, see how long a roof replacement takes.

Pre-project: inspection, estimate, and scheduling

Every project starts with an on-site inspection. The estimator climbs the roof to photograph existing damage, measure dimensions, and document the current condition of decking, flashing, and ventilation. These physical observations are paired with EagleView aerial 3D modeling, which provides measurements accurate to within 98.7% for material ordering.

The resulting estimate is fully itemized, covering tear-off labor, dumpster fees, material quantities with specific brands, ice-and-water shield coverage areas, ventilation specifications, and cleanup. No line is lumped into a vague “labor” category.

Once the estimate is approved, the project manager coordinates material delivery and schedules the installation date. Lead times in Connecticut typically run two to six weeks depending on seasonal demand.

Material selection

Shingle selection happens before the installation date is locked. The two most popular architectural products for 2026 are the GAF Timberline HDZ and the Owens Corning TruDefinition Duration.

Product	Algae Protection	Wind Warranty
GAF Timberline HDZ	25-Year StainGuard Plus	No Maximum Speed Limit
Owens Corning Duration	10-Year StreakGuard	130 MPH

Designer and luxury options are also available for homeowners who want the look of natural slate or wood shake. The project manager reviews samples and pricing for each tier so the decision is informed by both appearance and budget.

Installation day: site preparation (30-60 minutes)

The crew arrives early to secure the property before any material comes off the roof. This preparation step prevents damage to landscaping, siding, and the driveway surface.

• Tarps cover landscaping beds, shrubs, AC condensers, and any windows near the roofline
• The dumpster is staged on plywood sheets to protect the driveway from weight marks
• Safety rigging and ladder positioning are set for crew access
• Interior attic vents are covered from inside to block dust from entering the living space

Tear-off (2-4 hours)

Old shingles and underlayment are stripped down to the bare wood deck. A typical 20-square asphalt roof produces roughly 5,000 pounds (2.5 tons) of debris. West Hartford Roofing uses an Equipter RB4000 roofing buggy with a 4,000-pound capacity container that lifts to eave height, catching waste directly instead of throwing it onto the yard.

Roof Size	Debris Weight	Dumpster Size
15 squares	~3,750 lbs	10-15 yard
20 squares	~5,000 lbs	15 yard
30 squares	~7,500 lbs	20 yard

This phase is loud and dusty. Many homeowners choose to run errands until the noise subsides around midday.

Decking inspection and repair (30-90 minutes)

With the deck fully exposed, carpenters walk every square foot testing for soft spots, rot, and delamination. This inspection is the primary advantage of a full tear-off over a roof-over approach, because structural problems are identified and fixed before they are sealed behind new materials.

Damaged sections of 7/16-inch OSB or 1/2-inch plywood are cut out and replaced immediately. Each replacement sheet costs $30-$50 for the material in 2026, and the work is photographed for the homeowner’s records.

Waterproofing layer (1-2 hours)

Two materials create the secondary water barrier beneath the shingles. Self-adhering ice-and-water shield goes on first at the most vulnerable locations:

• Along all eaves, extending at least 24 inches past the interior wall line per CT building code
• Inside every roof valley where two slopes converge
• Around the chimney base, skylights, and all pipe penetrations

Synthetic underlayment (GAF Deck-Armor or Owens Corning Deck Defense) then covers the remaining deck surface. This woven material resists tearing far better than traditional 15-pound felt paper and provides a reliable moisture barrier if wind-driven rain gets past the shingle layer.

Edge protection: drip edge and starter course (30-45 minutes)

Aluminum drip edge is installed along all eaves and rakes. This metal flashing directs water cleanly into the gutter system and prevents moisture from wicking back under the shingle edges to rot the fascia.

A purpose-built starter strip is then nailed along the leading edges. The factory adhesive on these strips locks down the first row of field shingles and provides critical wind resistance at the most exposed part of the roof.

Field shingle installation (3-5 hours)

Shingles are installed from the eave upward toward the ridge in an offset pattern specified by the manufacturer. Proper nail placement in the reinforced nailing zone is essential for maintaining the wind warranty.

Standard inland installation uses four nails per shingle, roughly 320 nails per square. High-wind areas require a six-nail pattern at approximately 480 nails per square. The manufacturer’s specific nailing instructions are followed exactly.

Ventilation and ridge cap (30-60 minutes)

A continuous ridge vent is cut and installed at the peak to allow hot, moist air to escape from the attic. Connecticut enforces a 1:150 ventilation ratio, and the ridge vent provides the exhaust side of that equation. Matching cap shingles fold over the vent and hip joints for a clean finished appearance that keeps rain out of the ventilation slot.

Flashing and penetration sealing (1-2 hours)

Fresh step-and-counter flashing is fabricated and installed at every roof-to-wall junction, chimney, and skylight. New rubber pipe boots seal all plumbing vent penetrations. Transitions are sealed with professional-grade tripolymer sealants (Geocel 2300 or OSI RF140) that bond to damp surfaces and flex with temperature swings across Connecticut’s seasonal range.

Existing flashing is only reused if it is heavy-gauge copper or lead in verified good condition.

Cleanup and final walkthrough (45-90 minutes)

The ground crew removes all tarps, collects scattered debris, and runs high-powered neodymium magnets across the driveway, lawn, and garden beds two to three times to catch every nail. A standard tear-off scatters up to 10,000 old fasteners, making the magnetic sweep critical for property safety.

The project manager then walks the perimeter with the homeowner, reviews the finished roof replacement from every angle, and hands over warranty registration paperwork along with a complete photographic record of the decking repairs and installation phases.

Ready to start? Request a free estimate and the team will map out these roof install steps for your specific property.