Asphalt shingle roof cost

An asphalt shingle roof costs $386 to $749 per square installed, so a typical 20 square roof runs $8,200 to $15,400 with the permit. Architectural shingle at the national average is about $534 a square.

Four out of five American roofs are asphalt, and the reason is arithmetic rather than taste: nothing else covers a house for a third of the price of metal and lasts twenty-five years doing it.

Three-tab against architectural

Three-tab is a single flat layer, cut into tabs so it reads as separate shingles. $296 to $604 a square installed. It is thinner, lighter, rated for lower wind speeds, and lasts 15 to 20 years. Manufacturers have quietly stopped promoting it and some have discontinued lines.

Architectural, also sold as dimensional or laminate, bonds a second layer onto the first. $386 to $749 a square. It is heavier, casts a shadow line that reads as depth from the street, carries higher wind ratings, and lasts 25 to 30 years.

The gap is roughly $100 a square, or about $2,000 on a whole roof, and architectural is what nearly every quote will assume. Three-tab makes sense on a rental, a detached garage, or a house being sold within a couple of years.

Premium or designer shingles imitate slate or shake at $700 to $1,200 a square. They are heavier still and carry the longest warranties.

What a square costs, broken down

The material is the smaller half. That surprises people who have priced bundles at a home centre and assumed the rest is markup: the labour, the tear-off, the disposal and the crew's insurance are most of a roofing bill.

What the ratings actually mean

Wind rating. Shingles are tested to 110 or 130 mph. The rating only holds if they were nailed to the manufacturer's pattern, which usually means six nails per shingle rather than four in high-wind areas. It is the cheapest upgrade on a roof and the one most often skipped.

Impact rating. Class 4 is the top of the UL 2218 scale, and several insurers discount premiums for it in hail states. The shingles cost $50 to $100 more a square. In Texas, Colorado or Oklahoma the discount can pay that back in a few years, so ask your insurer before choosing.

Algae resistance. Copper granules mixed into the surface stop the black streaking that shows up on north-facing slopes in humid climates. Usually a few dollars a square and worth it east of the Mississippi.

The warranty number is not the life. A "lifetime" shingle warranty is prorated after the first ten or so years and covers material defects, not wear. What determines how long the roof lasts is ventilation, installation and sun exposure.

What is under the shingles matters as much

Underlayment. Synthetic has replaced felt on good jobs: it is stronger, does not tear in wind before the shingles go on, and does not wrinkle when wet.

Ice and water shield. A self-adhering membrane at the eaves and in the valleys. Northern codes require it a set distance up from the wall line. It is what stops an ice dam pushing water back under the shingles.

Drip edge. Metal along the eaves and rakes. Required by code in most places and still missing on plenty of older roofs.

Ventilation. Intake at the soffits and exhaust at the ridge. Without it an attic bakes the shingles from below and most manufacturers void the warranty.

Ask for these four by name. A quote that lists only shingles is quoting half a roof.

Frequently asked questions

How many shingles do I need?

Three bundles cover one square, which is 100 square feet of roof. A 2,000 square foot house with a standard pitch has about 25 squares, so 75 bundles plus 10% for waste, valleys and hips.

Can I put new shingles over old ones?

Code usually allows two layers, and it saves the tear-off, around $130 a square. It is still generally a bad trade: it hides deck rot, adds weight, shortens the new roof's life because it traps heat, and makes the next replacement more expensive.

Do darker shingles make the house hotter?

A little, and less than people think once the attic is properly ventilated. Reflective or "cool roof" shingles cut attic temperature measurably in the south and matter almost not at all in the north.

How long do they really last?

Twenty to twenty-five years for architectural in a moderate climate, less in intense sun, more in mild coastal weather. Poor ventilation is the most common reason a roof fails at fifteen instead of twenty-five.

What time of year should the work happen?

Shingles need warmth to seal down. Late spring through early autumn is ideal; below about 40°F the adhesive strip will not bond until the following summer, so winter installations need hand-sealing.