2. Next, you should calculate the length of one canvas. It equals the distance from the lower point of the floor to the highest point of the ceiling. This length should be divided into 10.5 (average length of one roll).
2. Next, you should calculate the length of one canvas. It equals the distance from the lower point of the floor to the highest point of the ceiling. This length should be divided into 10.5 (average length of one roll).