Replacing a roof is one of the costliest upgrades a homeowner can make.

Roofers look at several variables to determine the price of a new roof, including its size, pitch, accessibility and cost of materials. Because of this, prices for a new roof can range drastically. In terms of a ballpark figure, though, Michael Allen, owner of highly rated Above It All Roofing in Irvine, California, says a new roof can cost as low as $5,000 for an asphalt shingle roof — the most commonly used roofing material in America — to $25,000 and up for higher-end roof types. The average price, he says, is $12,000. Angie’s List members reported paying an average of $8,900 to replace an asphalt shingle roof in 2013.
“We’ve done [asphalt shingle] roofs for the Housing Authority here in Charlotte for lower-income people for as low as $4,000,” says Dan Hood, sales and marketing manager for H & S Roofing Company in Charlotte, North Carolina. “And [now] we’re in the process of putting on a $150,000 slate roof.”

The roof’s size

A roof’s size is the largest cost factor, Hood says.
Roofers charge per roofing square. A 10-by-10-foot (100 square feet) area is equal to one roofing square.
“For example, if we’re working on a roof that is 3,000 square feet, it’s broken down into 30 squares,” Allen says.

The roof’s pitch

Another variable in pricing is the roof’s pitch, or slope. Allen says a roof with a pitch of about a 7-12 ratio — the first number represents the height and the second the length — or higher isn’t walkable and may require extra safety harnesses and equipment. A 7:12 roof, for example, means that for every 12 inches it runs horizontally, the roof rises 7 inches vertically.
“A roof of 7:12 or greater is a steep roof, and we charge more money for that,” Allen says. “The work just goes a lot slower with a steep roof. You can’t stack stuff on the roof, and you have to wear harnesses.” Hood says H & S Roofing also charges more for pitches above 7:12 because of the difficulty and because the company pays more in insurance costs.
Another factor is accessibility to the roof.“Can we get a truck in there [close to the house]?” Allen says. “Can we back the truck against the house? If not, we’ll have to carry [the materials] all the way out to the trucks, and that can be more expensive.” Tearing off a heavier roof can also increase labor costs.

Type of roofing surface

According to Homewyse, which provides average costs for home improvement projects, the cost per square foot for a shingle roof is between $5.43 and $7.05. That equates to about $1,086 to $1,409 per 200 square feet (or for two squares).
Homewyse estimates the cost and labor for an asphalt roof for a 1,200 square foot house with a low slope at $3,000 to $4,100. A tile roof with the same dimensions may cost $7,500 to $9,300.
Highly rated roofers tell us that asphalt is the most affordable roofing option, followed by wood, metal, tile and slate.
“You can pay twice as much for a metal roof compared to asphalt shingles, and as much as five times more for slate,” Hood says.
While asphalt shingles may last 20 or more years, tile, metal and slate may last 50 or more years, which can play a role in determining the type you want.

Hiring a roofer

Before hiring a roofing company, the National Roofing Contractors Association recommends checking that its workers are licensed and insured. Ask to see a copy of the roofer’s proof of insurance.
Seek out several bids, and don’t just settle for the lowest one.
“Look at their online feedback,” Allen says. “Bottom line, make sure the company has a good reputation.”

Adapted from an article on Angie’s List by Tom Moor dated 06/19/14