10 Minute BidsSiding calculatorSquare feet, squares and lap pieces.
Enter each wall and gable end, and your windows and doors. You get the siding area, squares and the lap pieces for your exposure.
Your estimate
—
| Wallshow many × length × height | — |
|---|---|
| Gable ends½ × width × height | — |
| Wall area | — |
| Openings | — |
| After the openings | — |
| Waste | — |
| Siding to order | — |
| Squares100 sq ft each | — |
| One piece coversexposure × length | — |
| Piecesrounded up | — |
How we got it
Skip the math — upload your plans. We measure it all on a 3D model of your house.
Priced per plan setSiding bid, 3D model included
Upload your plansNot in these numbers: corners, starter, J-channel and trim, flashing where the roof meets the wall, and soffits. A siding takeoff from your plans lists every one of them.
This is an estimate from the numbers you enter. Plans don't show pony walls and other framing built in the field under the siding line, or walls changed during construction. Confirm measurements on site before you order.
The siding formulas.
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Wall area
Each wall is a rectangle, each gable end a triangle.
walls = how many × length × height · gable = ½ × width × height -
Openings
Left in by default: the uncut area over windows and doors covers the cut waste. Take them out and add a waste % instead.
openings in: to order = wall areaopenings out: to order = (wall area − openings) × (1 + waste %) -
Squares
A square is 100 sq ft of wall.
squares = square feet ÷ 100 -
Pieces
One lap board covers its exposure times its length.
one piece = exposure ÷ 12 × length · pieces = to order ÷ one piece, rounded up
Worked exampleTwo 40 ft and two 30 ft walls, 9 ft tall, are 1,260 sq ft, and two gables 30 ft wide and 7.5 ft tall add 225: 1,485 sq ft, or 14.85 squares. A 12 ft board at a 7 in exposure covers 7 sq ft, so 1,485 ÷ 7 = 212.1: 213 pieces.
| Board | Exposure | 12 ft piece | Per square |
|---|---|---|---|
| 5.25 in | 4 in | 4 sq ft | 25 |
| 6.25 in | 5 in | 5 sq ft | 20 |
| 7.25 in | 6 in | 6 sq ft | 17 |
| 8.25 in | 7 in | 7 sq ft | 15 |
| 9.25 in | 8 in | 8 sq ft | 13 |
| 12 in | 10.75 in | 10.75 sq ft | 10 |
Fiber-cement lap boards, 12 ft long, 1¼ in lap. Pieces per square rounded up.
Skip the math —upload your plans.
We build every wall of the house in 3D from your plan set and cut in the openings. Your siding bid lists wall area by elevation, every opening, corners, starter, flashing and gable ends. You spend about 10 minutes checking it against your plans.
Priced per plan setSiding bid, 3D model included
Or see what’s in a siding bid.
Siding questions.
Should I subtract windows and doors from siding?
Not by default here. Many siding crews side straight past the openings and cut them out later, so the area of the windows and doors covers the cut waste. Tick "Subtract the openings" to take them out, then add a waste %, typically about 10%.
How do I figure a gable end's siding area?
A gable end is a triangle: ½ × width × height, with the height from the top of the wall to the peak. A gable 30 ft wide and 7.5 ft tall is 112.5 square feet.
How many pieces of lap siding are in a square?
One piece covers its exposure times its length. A 12 ft board with a 7 in exposure covers 7 square feet, so a square of 100 square feet takes 14.3 boards: 15 once you round up.
What is a square of siding?
100 square feet of wall covered. Siding is priced and ordered by the square, so 1,485 square feet of wall is 14.85 squares.
Is this an exact siding order?
No. It's an estimate from the numbers you enter. Corners, starter, trim and flashing are extra, and walls change during construction. Confirm measurements on site before you order.