How to use
- Enter the room length, width, and the height you will paper.
- Enter how many doors and windows to subtract. Each door removes 21 square feet and each window removes 15, as a planning default.
- Enter the usable square feet per roll from the label, after you account for pattern repeat if the label already did that.
- Press Calculate. The roll count is rounded up.
How it's calculated
Gross wall area = 2 × (length + width) × height. Net area subtracts 21 square feet per door and 15 per window.
Area to cover = net × (1 + extra percent ÷ 100). Rolls = that area ÷ coverage per roll, rounded up.
Worked example
A 12 by 10 foot room with 8 foot walls has 352 square feet of wall. One door and one window leave 316. At 10 percent extra that is 347.6 square feet. A roll with 28 usable square feet means 13 rolls, because 347.6 ÷ 28 is about 12.41 and you cannot buy 0.41 of a roll.
Assumptions
Four walls, no closets, no sloped ceiling. The 21 and 15 square foot openings match the planning defaults used on the ClearQuip paint calculator. Measure an unusual door yourself and adjust the area before you divide. Double rolls and murals are not a separate mode.
FAQ
Why isn't coverage filled in?
Labels differ. A number we invented would order the wrong count.
What if the pattern repeat is large?
Raise the extra percent, or reduce the usable coverage to what you can actually place. Both boxes are yours.
Does this paper the ceiling?
No. Ceiling area is length times width, and you would divide that by the roll yourself.
Can I use this for one accent wall?
Enter that wall as if the room's perimeter produced only that area, or take length times height for the single wall and skip the other walls. The form assumes four walls.