Wallpaper calculator

Amount of cubic meters and amount of rolls of wallpaper as you enter the size of walls and the size of rolls

When you are starting the renovation, even the cosmetic one, you must be as precise as possible to calculate the number of necessary materials because nobody wants to overpay their hard-earned money. Due to the incorrect calculation there is often a problem of shortage or surplus of purchased materials.
That's why, according to the request Количество обоев на стену and my own needs I've tried to create a calculator for the necessary amount of rolls of wallpaper. And that's what I got:

PLANETCALC, Amount of wallpaper needed

Amount of wallpaper needed

Number of rolls
Amount of wallpapers, in cubic meters

Here is some explanation:
Room length, m - here you enter the perimeter of the room or your flat.
Room height, m - that's simple I guess.
Roll width, m - the width of the roll. It's usually 0.5, 0.56, 0.6, 0.75 etc.
Roll length, m - the length of the roll. It's usually 7, 10.5, 12 and 18 meters.
Width and length of doors and windows, m - here you enter the width and length of doors and windows. As we don't want them wallpapered this info is subtracted.
All the data is entered in meters. The calculator accounts 10 centimeters of each roll that usually needs to be cut off.