How to Shingle a Roof: A Guide

How to Shingle a Roof: Key Insights

• Layers: a shingle roof is really a system of layers, drip edge, underlayment, starter course, field shingles and ridge cap, and each part plays a distinct role.
• Pattern: shingle courses are staggered on purpose. A straight vertical seam down the roof is one of the most common signs of a rushed installation.
• Safety: roof work carries a real fall risk, which is why many homeowners hire a pro for anything beyond patching a small section.
• Cost: shingling a roof in Canada typically runs $4 to $9 per square foot, or $6,500 to $18,000+ for a full shingle replacement, depending on shingle type and roof complexity.

In this guide, you'll read about:

1. How Do You Shingle a Roof? An Overview
2. Signs You Need to Reshingle Your Roof
3. Types of Asphalt Shingles to Choose From
4. Tools and Materials for Shingling a Roof
5. How to Install Shingles on a Roof: Step by Step
6. How Much Does It Cost to Shingle a Roof?
7. Find a Roofing Pro on HomeStars
8. FAQs: Your Questions About Shingling a Roof Answered

How Do You Shingle a Roof? An Overview

So how do you shingle a roof, in plain terms? A shingle roof is built in layers, and each layer protects the one underneath it. Drip edge directs water off the roof deck and into the gutters. Underlayment sits between the deck and the shingles as a backup barrier. Shingles themselves go on in overlapping rows, called courses, starting at the bottom edge of the roof and working up to the peak.

The reason shingles are staggered from row to row, rather than stacked in straight vertical lines, is to stop water from finding a continuous path down through the seams. This is the part of the process most likely to go wrong on a rushed installation, and it's usually the first thing a roofer checks when inspecting someone else's work.

Signs You Need to Reshingle Your Roof

Most homeowners don't think about their shingles until something goes wrong. A few signs are worth watching for before that happens.

Curling or Cupping Shingles

Shingles that curl at the edges or cup in the middle have lost flexibility and are no longer sealing properly against wind and rain. This is common once a roof passes the 15-year mark.

Missing Granules

Asphalt shingles are coated in granules that protect against UV damage. If you're finding granules in your gutters or noticing bald patches on the shingles themselves, the protective layer is wearing thin.

Water Stains or Leaks

Stains on ceilings or in the attic are a sign that water is getting past the shingles somewhere. By the time a leak shows up inside the house, the underlayment has usually already failed in that spot.

Roof Age

Asphalt shingles typically last 15 to 30 years depending on the product and the climate. If your roof is approaching that range and hasn't had any major work done, it's worth having a roofer take a look.

Note: catching these signs early often comes down to routine upkeep. Our roof maintenance checklist walks through a seasonal inspection routine that can help you spot wear before it turns into a leak.

Types of Asphalt Shingles to Choose From

Not all shingles are built the same way, and the type you choose affects both the look of the roof and how long it lasts.

3-Tab Shingles

These are flat, single-layer shingles with a uniform look. They're the most affordable option and the lightest, but they generally carry the shortest lifespan of the three main types.

Architectural Shingles

Also called dimensional shingles, these are made of two or more layers laminated together, giving the roof more texture and a heavier, more dimensional appearance. They cost more than 3-tab shingles but hold up better against wind.

Luxury Shingles

Designed to mimic the look of slate or wood shake, luxury shingles are the thickest and most durable option. They come at a higher price point and are usually reserved for homes where the roofline is a visible design feature.

Tools and Materials for Shingling a Roof

Before starting the project, it helps to know what's actually involved in laying out a shingle roof correctly.

Item	Purpose
Roofing nail gun or hammer	Secures shingles and underlayment to the deck
Utility knife	Trims shingles to fit edges, valleys and vents
Chalk line	Marks straight, level courses across the roof
Tape measure	Confirms roof dimensions and course spacing
Ladder and fall-arrest harness	Provides safe access to the roof surface
Drip edge	Metal flashing along the eaves and rakes
Underlayment	Felt or synthetic membrane laid under the shingles
Starter shingles	First course laid at the roof's lowest edge
Field shingles	The main shingles used across the bulk of the roof
Ridge cap shingles	Shingles designed to seal the peak of the roof
Flashing	Metal used around chimneys, vents and valleys

How to Install Shingles on a Roof: Step by Step

Here's how to install shingles on a roof, from a bare deck to a finished ridge.

Step 1: Clear the Roof Deck

Remove any old shingles, nails and debris down to the bare deck. Inspect the plywood or OSB sheathing underneath for soft spots or rot, and replace any damaged sections before moving forward. Skipping this step is one of the most common reasons a new roof fails early.

Step 2: Install the Drip Edge

Run drip edge flashing along the eaves first, nailing it every 12 inches or so. The rake edges (the sloped sides of the roof) are typically installed after the underlayment goes down.

Step 3: Add the Underlayment

Roll out felt or synthetic underlayment starting at the bottom of the roof, overlapping each row by at least 2 inches. In areas prone to ice damming, an adhesive ice and water membrane is typically added along the eaves for extra protection.

Step 4: How to Measure a Roof for Shingles

Roofing is sold by the square, where one square covers 100 square feet. To measure a roof for shingles, multiply the length and width of each roof plane, add the sections together, and divide by 100 to get the total number of squares. Add 10 to 15 percent to that total to account for waste, cuts around vents and chimneys, and mistakes. Steeper roofs and roofs with a lot of valleys or dormers will need more waste allowance than a simple gable roof.

Step 5: Lay the Starter Course

Install a starter course of shingles along the bottom edge, with the tabs cut off so only the adhesive strip faces down. This row seals the bottom edge and prevents wind from lifting the first row of field shingles.

Step 6: Install the Shingle Courses

Working from one bottom corner, lay each course of shingles so the seams are offset from the row below. Snap chalk lines as you go to keep each course straight, and follow the shingle manufacturer's nailing pattern, typically four to six nails per shingle, placed just below the sealant strip.

Step 7: Flash the Valleys, Chimneys and Vents

Install metal flashing anywhere the roof meets a vertical surface or changes direction, including valleys, chimneys, skylights and vent pipes. These transition points account for a disproportionate share of roof leaks, so this step is worth doing carefully rather than quickly.

Step 8: Cap the Ridge

Finish by installing ridge cap shingles along the peak, overlapping each piece to shed water in the direction it naturally flows off the roof. This is the last layer and the one most visible from the ground.

For a broader look at how shingle costs compare to a full tear-off and replacement, see our roof replacement cost guide.

Get quotes from roofing pros on HomeStars

How Much Does It Cost to Shingle a Roof?

Shingling costs come down to the size of the roof, the shingle type, and how much prep work is needed before installation can start.

Cost Factor	Typical Range
Basic asphalt (3-tab) shingles (per square foot)	$1 to $3
Architectural shingles (per square foot)	$3 to $6
Premium or designer shingles (per square foot)	$6 to $9
Full shingle replacement (average home)	$6,500 to $18,000+
Labour (share of total cost)	40 to 60%

Complexity adds to the total as well. A steep roof, multiple valleys, or a lot of dormers and skylights all increase labour time, which is usually the biggest line item on a roofing quote. Extra costs like deck repairs, disposal fees and permits aren't always included in an initial quote, so it's worth asking a roofer what's covered before work starts. For a full breakdown of what drives shingle replacement pricing, see our shingle replacement cost guide.

Compare quotes from local roofing pros

Find a Roofing Pro on HomeStars

Shingling a roof is technical, physical, and unforgiving of shortcuts, which is why most homeowners bring in a professional rather than tackling the whole project themselves. HomeStars makes that search easier. Post your project for free and hear back from interested roofing pros in your area, then compare their profiles, past customer reviews and photos of previous roofs before deciding who to contact. You can also browse our roofing pros near you page to see available roofers in your area before posting a project.

Find a roofing pro on HomeStars

FAQs: Your Questions About Shingling a Roof Answered

Do you need a permit to reshingle a roof in Canada?

It depends on your municipality and the scope of the work. A straightforward like-for-like shingle replacement often doesn't require a permit, but work that involves structural repairs to the deck, changes to the roofline, or a full tear-off in some cities can. Check with your local building department before work starts, or ask a roofing pro found through HomeStars to confirm what applies in your area.

Can new shingles go over an existing layer, or does the old roof need to come off first?

Some building codes allow one layer of new shingles to go over an existing layer, up to a limit (often two layers total). That said, most roofers recommend a full tear-off, since it lets them inspect and repair the deck underneath, and a second layer adds extra weight and can shorten the lifespan of the new shingles. Ask your roofer whether your existing roof is a candidate for an overlay or needs a full strip.

How many bundles of shingles does an average roof need?

Shingles are sold in bundles, and most 3-tab and architectural products run three bundles to a square (100 square feet). A 2,000-square-foot roof with a typical waste allowance would need roughly 60 to 70 bundles, though this varies by manufacturer and shingle style. A roofing pro can give you an exact count based on your roof's measurements and pitch.

What's the best time of year to shingle a roof in Canada?

Late spring through early fall tends to be the busiest and most predictable window, since asphalt shingles seal best in moderate temperatures and dry conditions. Shingling in cold weather isn't impossible, but the sealant strips on the shingles bond more slowly below about 4°C, and some manufacturers have specific cold-weather installation requirements. If a repair can't wait for better weather, a roofing pro will know how to adjust the process.

Do new shingles affect a home's insurance or resale value?

Many insurers ask for the age and condition of a roof when setting premiums, and a roof nearing the end of its lifespan can sometimes lead to higher rates or added conditions. On the resale side, a recently reshingled roof is often noted favourably in a home inspection, since it signals one less major expense for a buyer to plan for. If you're weighing the timing of the work, a roofing pro connected through HomeStars can give you a sense of how your current roof is likely to be viewed.