Deal with the insulation substance as homogeneous, Whilst in real purposes, rigid materials have joints and even cracks. So, the U-value is usually greater than what It will be If your insulation behaved like a homogeneous product. Reference two presents assistance on calculating U-values. Disadvantages: it’s not generally by far https://jaroslavx196lhc6.thekatyblog.com/33479081/the-2-minute-rule-for-window-insulation