#### Calculating square footage of wall minus openings

Assume this is your wall

To calculate the square footage of your wall take the length 26' and the height 9'of the wall and multiply these by each other.

26' * 9' = 234 sq. Your wall has a total area of 234 square feet.

Calculate the square footage of your wall openings:

Window = 5' * 4' = 20 sq.

Door = 3' * 6'8" = 20.1 sq.

Add them together (ignore the .1) 20sq.ft + 20 sq. = 40 sq.

Subtract the total openings area from the wall sq. footage:

234 - 40 = which leaves 194 sq. ft. of wall area you want to cover with siding.#### Calculate the lineal area factor of your siding.

Example

Calculating the area factor for lineal feet of 8" wide bevel siding:

Nominal is what you call it, a 1 x 8 or 2 x 4

Dressed is the actual size

Exposed face is assuming a 1" overlap 7 1/2 dressed - 1 overlap = 6 1/2

Lineal foot area factor = 12 divided by 6 1/2 = 1.84615 round to two digits your area factor for this piece of siding is 1.85#### Calculating the amount of siding needed for your wall.

Square footage of your wall minus openings = 194 sq. ft.

Lineal foot area factor for your 8" wide piece of siding = 1.85

194 sq. * 1.85 l.a.f. = 358.9. Round it up 359.

The result you need 359 lineal feet of 8" bevel siding to cover your wall.