Roofing Squares Calculator

Enter your measurements

ft
ft
/12
%

Extra to cover cuts, breakage, and mistakes.

Results

  • Roof area1,476 sq ft
  • Roofing squares14.76 squares
  • Footprint1,200 sq ft
  • Slope multiplier1.118

Estimated cost

Material$1,550 – $2,509
Installed (with labor)$5,165 – $8,265

per roofing square installed (asphalt)

Material cost covers asphalt shingles only, per roofing square (100 sq ft), based on widely available architectural/dimensional products in 2026; premium impact-resistant or designer lines exceed this range. Installed cost adds labor, synthetic underlayment, ice-and-water shield at the eaves, and a standard single-layer tear-off; it excludes decking replacement, new drip edge, and skylight or chimney flashing.

Estimate only — prices vary by region, supplier, and season. Get a local quote before buying.

A roofing square is the unit contractors use to quote and order materials — one square equals 100 square feet of finished roof surface. This squares roofing calculator converts your building's footprint into actual roof area by applying the slope multiplier for your pitch, then divides by 100 to give the number of squares you need. It also adds a waste allowance you set, since cutting shingles around valleys, hips, and rakes always leaves scrap. Asphalt shingles are sold by the bundle, with three bundles covering one square for most three-tab and architectural strips. Knowing your square count before calling a supplier prevents under-ordering on delivery day and gives you a real basis for comparing bids. A 10% waste factor is standard for simple gable roofs; hip roofs and cut-up designs with multiple valleys often warrant 12–15%. The calculator shows both raw roof area and waste-adjusted squares, so you can see exactly what is driving the number — the footprint, the pitch multiplier, or the overage you chose.

How it’s calculated

Roof area = Footprint (Length × Width) × slope multiplier for the pitch. Squares = Roof area ÷ 100.

Worked example

For a house with a 50 ft by 28 ft footprint and a 5/12 pitch, the slope multiplier is 1.0833, which stretches the 1,400 sq ft footprint to about 1,517 sq ft of actual roof surface. After adding the 10% waste allowance, the calculator returns a roof area of 1,668 sq ft and 16.68 squares — round up to 17 squares, or about 51 bundles of standard architectural shingles.

Inputs

Building length
50 ft
Building width
28 ft
Roof pitch (rise per 12)
5 /12
Waste / overage
10 %

Result

Roof area
1,668 sq ft
Roofing squares
16.68 squares
Footprint
1,400 sq ft
Slope multiplier
1.0833
Estimated material cost
$1,752 – $2,836

Materials & pricing near you

Asphalt shingles, the most common US roofing material, are sold in bundles at lumber yards and big-box stores, with three bundles equaling one square for most architectural (laminated) products. Three-tab shingles run cheapest; dimensional/architectural shingles sit mid-range; designer and impact-resistant lines carry a premium. Roofing is a seasonal trade: summer demand and post-storm surges push material prices and installer availability upward, while late fall and winter often bring better contractor pricing in northern states. Many suppliers set a minimum delivery (often around 10 squares) or charge a drop fee on small loads, and bundles are heavy enough that rooftop loading is usually an added service. Most jurisdictions require a permit for a full tear-off and re-roof, so check with your local building department before scheduling.

Frequently asked questions

How do I measure my roof pitch if I don't have plans?

Use a level and a tape measure. Hold the level horizontally against the roof slope, mark 12 inches out from one end, then measure straight up from that mark to the underside of the level — that vertical rise is your pitch. A 6-inch rise over a 12-inch run is a 6/12 pitch. You can do the same in the attic by resting the level on a rafter. That rise-per-12 number feeds directly into the slope multiplier the calculator uses.

Why does pitch matter if I already know my footprint?

Steeper roofs have more surface area over the same footprint. A 1,400 sq ft footprint at a 4/12 pitch becomes roughly 1,476 sq ft of actual roof surface; the same footprint at 8/12 becomes about 1,683 sq ft. Ordering by footprint alone on a steep roof means you'll run short. The slope multiplier corrects for this, and the gap widens on larger houses — easily several squares.

How many bundles of shingles does one roofing square require?

For standard three-tab and most architectural (dimensional) shingles, it's three bundles per square. Some heavier designer or slate-look products ship four or even five bundles per square because each bundle is heavier and covers less area. Always confirm the square-foot coverage printed on the bundle wrapper before ordering, since coverage varies by product line.

Should I order extra beyond the waste percentage?

It's worth ordering a little extra. Shingle color can vary slightly between production runs, so coming up short and reordering later may produce a visible mismatch on the same roof plane. Leftover shingles are also useful for future repairs after wind or hail damage. A common rule of thumb is one extra bundle, on top of your waste-adjusted total, with more on roofs that have lots of valleys, dormers, or hips.