What is a siding square?
A square is 100 square feet of coverage, the standard unit siding is priced and ordered in.
Siding Calculator
Estimate siding squares and accessory linear feet.
You'll need — squares of siding for — sq ft of wall.
Siding material
Waste defaults update for the selected material but stay editable.
Wall dimensions
Perimeter and height drive gross wall area; corner count drives corner trim.
Gables and openings
Optional — gables add triangular wall area; openings subtract from net coverage and set the trim run around each one.
House wrap and battens
Product sizes. House wrap is sized on the gross wall because it is cut out at the openings afterwards.
You'll need — squares of siding for — sq ft of wall.
You'll need
Siding results
Warnings
- ERROR Enter the wall perimeter -- without it there is no wall area to cover.
- ERROR Enter the wall height -- perimeter alone does not give an area.
Not counted -- answer these to add them
- Corner posts
- How many outside corners the walls turn. The perimeter cannot tell us -- a rectangle and an L-shaped footprint measure the same and need different amounts of corner board.
Detail values
- Gross wall area
- — sq ft
- Gable area
- — sq ft
- Net area
- — sq ft
- Opening trim
- — linear ft
- House wrap
- — rolls
Assumptions
- Material: Vinyl
- Corner count: not entered — corner board not counted
- Estimated waste: 10% for an average project
- House wrap coverage: 900 sq ft per roll — the nominal 9 ft x 100 ft face. No seam or corner lap is deducted, so a roll covers somewhat less wall than this.
- J-channel: not counted — an opening entered as an area has no edge to trim
- Siding fasteners: Aluminum nails at 0.005 lb per sq ft of siding (Vinyl Siding Institute installation manual: 0.005 for aluminum nails, 0.01 for roofing nails, staples and screws). Switch the fastener type if you are using the other.
Included: siding squares, starter strip, opening trim (J-channel or casing), house wrap, siding fasteners, by weight.
Not included: labor, delivery, permits, disposal of waste material.
Formula details
- Net wall area: perimeter x wallHeight + gables - openings
- Squares: netArea x (1 + wastePercent / 100) / 100
- House wrap rolls: ceil((grossWall + gables) / coveragePerRoll)
Sized on the gross wall: the wrap is run over the openings and cut out afterwards.
Material List
About this calculator
Enter the wall perimeter, wall height, and corner count -- plus any gables and openings -- to get siding squares and starter strip, corner, and opening trim linear footage.
FAQ
Are openings subtracted from wall area?
Yes. Enter each opening's width and height in the Openings box, in inches -- the area comes off the wall for you, and the width and height also give the run of trim around each one. A bare number is read as an area in square feet and gets no trim.
Does waste apply to accessories too?
Not to the linear footage. The editable waste factor is applied to the siding squares, and to the fastener weight, which is counted off that waste-adjusted area. Starter strip, corner trim, opening trim, house wrap and battens are net lengths -- add your own allowance for cut-offs.
Disclaimer
Material estimate only. Verify local wind, exposure, and manufacturer installation requirements.