Feb 16, 2019 · In other words the gross area of tight packed poly tubes will take up about 1/0.65 = 1.54 x the gross area of OKU panels, and since a loose spaced design takes 1.04/0.65 =1.6 x the area of a tight packed design to produce the same heat, a loose spaced design takes 1.54 x 1.6 = 2.5 x the square area of OKU panels to produce the same energy. Keep