How roofing materials are sold

Most roofing is sold by the “square,” enough to cover 100 square feet of roof area. Our sample house — a typical two-story, 2,300-square-foot house with a medium-pitch roof — has a roof area of about 1,500 square feet. Double that if the house is only one story. Note: All costs are approximate.

Composition shingles

Commonly called asphalt shingles, these are the most popular residential roofing material in the country. Most products consist of a fiberglass mat between two layers of asphalt. Tiny stones embedded in the top help protect the shingles from the sun’s damaging rays.

Basic three-tab shingles have slits in the front, so each piece looks like three small shingles. Architectural shingles are a more upscale choice. They are thicker, longer-lasting, and don’t have slits where debris can collect. They also create a more textured look, which many people prefer.

Benefits: Relatively inexpensive, and all roofers know how to install them. Good fire resistance. Some types are suitable for hail regions and available with wind warranties up to 130 mph. May contain zinc or copper to inhibit algae growth.

Drawbacks: Typically last only 20 years and need periodic cleaning to remove moss and debris.

Green factor: Some types have a reflective coating that can lower cooling costs. Though theoretically recyclable, most worn shingles end up in landfills.

Cost per square foot: $2-$4, installed

Average two-story, 2,300 square foot house, including removal of one layer of roofing: $7,000 

Wood shingles and shakes

Traditional and beautiful, wood is no longer as popular because quality has declined, and because of rising concerns about fire. Shakes are thick and have a rough, split surface; shingles are thinner and sawn flat. Both types must be installed over spaced boards, not solid sheathing, so the roofing can dry.

Benefits: In dry climates, shakes and shingles perform well; some shakes have up to a 50-year warranty. Thicker shakes can be used where hail is severe.

Drawbacks: Not fire-resistant unless treated, so some building codes prohibit them. Thinner products can be damaged by hail. In wet climates, wood must be cleaned periodically to remove moss and lichen.

Green factor: Roof-quality shakes are cut from old-growth trees. Worn-out roofing can be recycled into mulch, provided it hasn’t been treated with pesticide.

Cost per square foot: $5-$12, installed

Average two-story, 2,300 square foot house, including removal of one layer of roofing: $17,200.

Metal panels and tiles

Once found mostly on commercial and farm buildings, metal roofing is now the fastest-growing residential roofing material. There are two basic kinds: standing-seam panels and tiles. Panels come in pieces around 16 inches wide and up to 20 feet long, so they reach without a seam from the ridge to the gutters. Metal tiles can mimic the look of wood shingles or shakes.

Benefits: Extremely long-lasting; some come with lifetime warranties. Good fire resistance, and some styles are strong enough to resist wind and heavy hail. Panels go up quickly and require little maintenance.

Drawbacks: Higher initial cost than composition shingles. Tile roofs have numerous grooves that trap leaves, so they need frequent cleaning.

Green factor: Styles with reflective coatings reduce cooling demand by 10% to 15% and can qualify for a federal energy efficiency tax credit of up to $500.

Cost per square foot: $3.50-$11, installed

Average two-story, 2,300 square foot house, including removal of one layer of roofing: $16,800.

Clay or concrete tiles

Red clay tiles are an essential feature of Spanish-style homes in much of the Southwest and Florida. In addition to traditional styles, clay and concrete tiles can mimic wooden shingles or shakes, while others look almost like slate.

Benefits: Long-lasting; some manufacturers offer lifetime warranties. Well-suited to relatively dry climates, and will not burn.

Drawbacks: Heavy, so the roof structure must be able to support the weight. They can be damaged by hail. Concrete tiles are moss magnets in damp climates; use glazed tiles instead.

Green factor: Long-lasting clay and concrete tiles can be reused and eventually recycled into new building materials.

Cost per square foot: $5.50-$10.50, installed

Average two-story, 2,300 square foot house, including removal of one layer of roofing: $17,500

Slate

Quarried in the Northeast and Virginia, slate is much more common in the East than in the West. Because slates hang from nails and are not glued down, they are best suited for fairly steep roofs that shed water quickly.

Benefits: Slate can last for decades, doesn’t burn, and sheds snow and rain well.

Drawbacks: Slate is expensive and requires skill to install and repair, which can be an issue where such roofs are rare. The roof structure must be able to support the heavy weight.

Green factor: Slate is a natural material, and slicing it into shingles requires little energy. If a building with a slate roof is torn down, the slates can be reused.

Cost per square foot: $10-$20, installed

Average two-story, 2,300 square foot house, including removal of one layer of roofing: $29,300.