Siding calculator
Enter an address to estimate net exterior wall area and siding squares from Google's aerial roof outline and your story count. Or type wall dimensions for siding quantities with waste. We haven't published a wall-area test yet; check openings and wall heights on site before ordering.
Updated
By stories
- 1 story1,666 sq ft
- 2 stories3,208 sq ft
- 3 stories4,695 sq ft
Measurements from Google aerial roof data, measured by the same engine Measured Bid prices from. No prices are shown here. Confirm every number on site.
At a glance
| Input | What you get |
|---|---|
| Address and stories, or wall dimensions and openings | Net wall area, siding squares and area by stories; typed mode adds material quantities |
| Openings, waste and material choice | Net siding squares, vinyl cartons or fiber cement planks |
How to calculate siding squares
Siding is ordered by the square: 100 square feet of wall. The calculator gets there in five steps.
- Measure the wall perimeter. From the air, that's the roof outline less the overhang on each side (18 inches to start).
- Multiply by the wall height. The calculator starts at 9 feet per story.
- On gable roofs, add the triangles above the end walls.
- Take off windows and doors. The calculator starts at 10% for siding.
- Divide by 100 for squares of siding.
MeasuredOur model house, one story
- Wall perimeter
- 184 ft
- × 9 ft wall height × 1 story
- 1,653 sq ft
- Gable ends
- + 198 sq ft
- Windows and doors (10%)
- − 185 sq ft
- Net wall area
- 1,666 sq ft
- 1,666 ÷ 100
- 16.7 squares
The same house at two stories has 3,208 sq ft of net wall area.
Vinyl cartons and Hardie planks
Squares tell you how much wall to cover. The order is in cartons or pieces, so convert after you add waste.
- Vinyl: divide the squares by the squares in a carton and round up. Double 4 and double 5 inch panels in Alside's Odyssey Plus and Mastic's Carvedwood 44 lines come 2 squares to a carton (Alside, Mastic). Some longer panels come 1 square to a carton.
- Fiber cement lap: each plank covers its exposure times its length. Hardie Plank is 12 ft long, and the table shows the exposure for each width from James Hardie's specs.
- Trim, corners, J-channel, soffit and starter strip are ordered by the piece or the foot, on top of the siding. The soffit calculator counts the soffit panels and channel.
- Board and batten: the board and batten calculator counts siding sheets or boards and the battens, wall by wall.
ExampleHardie Plank on our typed-walls example
| Plank width | Exposure | Planks a square | Planks with waste |
|---|---|---|---|
| 5.25 in | 4 in | 25.0 | 317 |
| 6.25 in | 5 in | 20.0 | 254 |
| 7.25 in | 6 in | 16.7 | 212 |
| 8.25 in | 7 in | 14.3 | 181 |
| 9.25 in | 8 in | 12.5 | 159 |
| 12 in | 10.75 in | 9.3 | 118 |
1,151 sq ft of net wall with 10% waste is 1,266 sq ft to cover. In vinyl at 2 squares a carton, that's 7 cartons. Planks are 12 ft; counts round up.
How this measures
- The wall model starts with Google's aerial roof outline, subtracts the overhang, multiplies by stories and wall height, adds gable ends and deducts an allowance for openings.
We haven't published a wall-area test yet. Address measurements use model assumptions for wall height and openings.
Measurement methods and published testsWhat it can't see
Wall area from the roof outline is a fast starting number. Walk the house before you order.
Measure these on site
- Individual windows, doors and garage doors.
- Stone, brick or other walls that won't get siding.
- Walls that step down a slope, like a walkout basement.
- Porches, bump-outs and walls tucked under a roof line.
- Detached garages and sheds. The calculator measures the house you confirm.
- Wall heights, including each story and gable end.
Siding or paint
- Painters and siding crews deduct different shares for openings. On the model house that's 1,666 sq ft for siding and 1,574 sq ft for paint.
- Measured Bid prices both trades from the same wall model, each with its own settings.
- We haven't published a wall-area test yet. Treat the number as a starting point.
Price it with your rates
Siding is priced per square foot for each material, with tear-off, trim, an adjustment for taller houses and a job minimum. You set each one in Measured Bid.
FAQ
How many squares of siding do I need?
Divide the net wall area by 100. That gives squares of wall to cover. Add a waste allowance for cuts and trim before you order. Your supplier or the siding maker lists one for each product.
How many boxes of vinyl siding do I need?
Divide the squares, with waste, by the squares in a carton and round up. Alside's Odyssey Plus and Mastic's Carvedwood 44 double 4 and double 5 inch panels come 2 squares to a carton. Some longer panels come 1 square to a carton, so check the label.
How many Hardie planks are in a square?
Divide 100 sq ft by the face each plank covers: its exposure times its length. James Hardie's 8.25 inch lap plank is 12 ft long with a 7 inch exposure, so it takes 14.3 planks to cover a square, before waste.
Is the siding calculator free?
Yes. Measuring from an address needs a free Measured Bid account, with 5 measurements free and no credit card. Changing the story count on the same house doesn't count toward that limit. Typing the walls has no limit.
How exact is the wall area?
It's estimated from the roof outline and the story count, less a share for windows and doors. It doesn't see individual openings, stone or brick sections, or walls that step down a slope. We haven't published a wall-area test yet. Measure the walls on site before you order.
Does it work for exterior painting?
Yes, as a starting point. Painters usually deduct a bigger share for windows and doors. Measured Bid's painting estimates start at 15% and siding at 10%. You can change both.
Can I put a siding price on my website?
Yes. Measured Bid's website price form measures the walls the same way and shows the homeowner a price range from your rates for each material.
Related pages and tools
Price siding from an address
Type the address. Your free account measures it, and you can price it with your own rates when you're ready.