Photo of roofers installing new shingles by DolfinDans/Flickr.

If you've ever had a roof replaced, you know that the majority of the cost is in the labor. But that doesn't mean the cost of materials is anything to sniff at, and the prices for shingles alone vary widely. That's why a new roof can run you anywhere from $225 to $1,000 and up per square. What's a square? Read on.

How Shingles are Measured
The standard unit of measurement in the roofing industry is the square, which means 100 square feet of installed roofing. In this case, "installed" does not include the labor cost; it's the amount of roof area that's covered when the shingles are installed, which affects the total cost to install shingles on a roof. As an example, if a plane of your roof measures 25 feet long and 20 feet from the eave to the peak, the total area is 500 square feet (20 x 25 = 500), or 5 squares. Calculate the squares for each roof plane and add them up, then add a bit for the peak shingles, or "caps," for a total shingle amount. Of course, you'll need some other materials for a complete roof installation (discussed below), but knowing the number of squares required gives you a simple basis for comparison shopping.

Costs of Popular Shingle Types
Roofing is a lot like kitchen counters: Despite the endless hype and industry buzz around the latest trendy materials, most homeowners stick with the old, familiar standards. In the case of countertops, it's plastic laminate. In the case of roofing, it's asphalt shingles. Asphalt shingles come in two main types: basic 3-tab (or "flat") style and architectural style (also called "laminate" for their layered construction that gives them visual texture). Other players in the shingle market include traditional wood and an assortment of recycled materials such as metal, rubber and plastic-composite. Be aware that prices for materials vary by region, and the only price that really matters is the one given by your local home center, supplier or chosen roofing contractor.

Asphalt
Retail price for 25-year, 3-tab shingles is about $25 to $30 per bundle, plus tax. You need three bundles per square, so the total price is around $75 to $90 per square. For architectural shingles, the retail price jumps to about $33 to over $52 per bundle, or $100 to $160 per square. Architectural shingles typically have higher wind ratings and longer warranties than standard 3-tab materials.

Wood
Cedar is the most common type of wood shingle roofing, but there are other species available, including redwood, cypress and pine. Shingle type varies, too. Classic sawn shingles are sawn on both sides and have a uniform thickness; taper sawn shakes are smooth on both sides and have natural thickness variation; split shakes are rough on both sides; and split and sawn shakes are rough on the top side, smooth on the back. Other factors affecting the shingle price are grade of material, shingle length and applied treatments for fire- and moisture-resistance. The cost for cedar shingles runs about $175 to $275 per square.

Recycled Roofing
Pinning down a material price for recycled roofing is nearly impossible. Part of the problem is that many of these products are made in Canada, so exchange rates come into play, as do distribution costs. One major manufacturer of plastic-composite shingles (made primarily with recycled plastic, agricultural fiber and rubber) claims its roofing is priced similarly to premium cedar shingles. Recycled rubber shingles are roughly twice the cost of standard asphalt roofing.

Other Materials Costs
Ridge, or cap, shingles can be cut from standard 3-tab shingles; each shingle yields three caps for a total of about 15 linear inches of coverage along the length of the ridge. For architectural shingles, you have to buy individual ridge shingles designed for this purpose. These might start at about $50 for 20 linear feet of coverage. Asphalt and some other shingle types need a course of "starter" shingles along the eave. Asphalt starter material comes in roll and shingle form and costs about to $0.60 to $1.25 per linear foot of coverage.

Additional materials costs of a complete roof include (as applicable) the underlayment, including roofing felt and ice damn membrane; drip cap, the metal edging along the eaves and rake (sloping side edge of a roof plane); nails; flashing, including step flashing for things like skylights and chimneys, boot flashing for plumbing pipes and vents, and valley flashing where two roof planes meet to form a gully; and caulk or roofing cement.