How Many Squares Is My Roof? (By House Size and Pitch)
A house with a 30 ft by 40 ft footprint under a gable roof at 6 in 12 has about 1,341.64 ft² of roof, which is 13.42 squares: roof area is the footprint times the pitch's area factor, never the floor area.
Estimates for planning, not professional advice. Read the full notice.
Work it out for your own sizes
Work out the squares for your own roofExample to try: Length 40 ft, Width across the roof 30 ft, Pitch 6 in 12, Overhang 0 in
Roof area, squares and bundles by footprint and pitch
Gable-roof area, squares of roof and bundles of the default shingle for three house footprints at three pitches, with no overhang
| Footprint and pitch | Footprint, flat | Roof area | Squares of roof | Bundles with 10% waste |
|---|---|---|---|---|
| 30 by 40 ft at 4/12 | 1,200 ft² | 1,264.91 ft² | 12.65 squares | 42 bundles |
| 30 by 40 ft at 6/12 | 1,200 ft² | 1,341.64 ft² | 13.42 squares | 45 bundles |
| 30 by 40 ft at 8/12 | 1,200 ft² | 1,442.22 ft² | 14.42 squares | 48 bundles |
| 30 by 50 ft at 4/12 | 1,500 ft² | 1,581.14 ft² | 15.81 squares | 53 bundles |
| 30 by 50 ft at 6/12 | 1,500 ft² | 1,677.05 ft² | 16.77 squares | 56 bundles |
| 30 by 50 ft at 8/12 | 1,500 ft² | 1,802.78 ft² | 18.03 squares | 60 bundles |
| 40 by 50 ft at 4/12 | 2,000 ft² | 2,108.19 ft² | 21.08 squares | 70 bundles |
| 40 by 50 ft at 6/12 | 2,000 ft² | 2,236.07 ft² | 22.36 squares | 74 bundles |
| 40 by 50 ft at 8/12 | 2,000 ft² | 2,403.7 ft² | 24.04 squares | 80 bundles |
Estimate for planning, from what you entered and the product data shown. Check product labels and your supplier before you buy.
A footprint is the floor area of a one-story house. Squares are the roof area in hundreds of square feet, before waste. Bundles use the shingle named below, with the simple-roof waste allowance added to the area and one round up. Product names are trademarks of their owners. HoneyDoMath is not affiliated with, sponsored by or endorsed by these makers.
The same footprint with an overhang, and as a hip roof
Roof area, squares of roof and bundles for one footprint at one pitch, as a gable roof with two overhangs and as a hip roof
| Roof | Roof area | Squares of roof | Bundles with the waste allowance |
|---|---|---|---|
| Gable roof, no overhang, 10% waste | 1,341.64 ft² | 13.42 squares | 45 bundles |
| Gable roof, 1 ft overhang, 10% waste | 1,502.64 ft² | 15.03 squares | 50 bundles |
| Gable roof, 2 ft overhang, 10% waste | 1,672.58 ft² | 16.73 squares | 56 bundles |
| Hip roof, no overhang, 15% waste | 1,341.64 ft² | 13.42 squares | 47 bundles |
Each overhang is added on the eaves and the rakes alike. The hip roof row uses the complex-roof waste allowance, because a hip roof has more cuts.
What changes for the same footprint
Pitch and overhang both change the roof area of one footprint: the second table works the same footprint with each overhang and as a hip roof, with a different waste allowance for the hip roof. The waste setting in the roofing calculator is where a cut-up roof with valleys and dormers takes more.
Floor area is not roof area. A two-story house has about half its floor area as footprint, so its roof is the smaller footprint times the pitch's area factor.
How the bundles are counted
The bundle column counts GAF Timberline HDZ bundles. Its sheet prints 3 bundles per square[1], and prints no coverage per square, so the count takes a square as 100 ft². Other shingles print other figures: see bundles in a square, by shingle.
Questions
How many squares is a 2000 sq ft roof?
A floor area of 2000 sq ft is not a roof area. The 40 by 50 ft rows of the first table are a one-story house of that size: the squares column gives the roof at each pitch.
How many bundles of shingles for 1500 square feet?
The 30 by 50 ft rows are a one-story house of 1500 sq ft footprint. The bundles column counts the default shingle at each pitch with the waste allowance; other shingles print other bundles per square.
How many square feet of roof sit on a 1500 sq ft house?
For a one-story house, read the roof area column in the 30 by 50 ft rows: it is the footprint times the pitch's area factor. A two-story house with the same floor area has about half that footprint.
How do I get roof area from house size?
Take the footprint of the house, not its floor area, and multiply by the area factor for the pitch. The roofing calculator does this for each roof section and adds the overhang and waste you set.
Calculate it for your project
Enter your own sizes to get the amount to buy or the layout figures, with the working shown and a page to print.
Try your own house in the roofing calculatorSources (1)
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Timberline HDZ Shingles Specification Sheet (opens in new tab), GAF, RESGN467HDZ-0526, 2026.
Manufacturer data.
“Bundles/Square: 3 Pieces/Square: 64”
Per GAF's specification, checked Nov 12, 2026. Figures and codes change; verify with the source. Back to where this is used (Source 1)
These are summaries of what the sources say, not professional advice. Codes and product data change. Check with your building department and the product label about your own project.