Observe: These values are for the center of glass only. They must only be applied to compare the result of different glazing styles, not to compare total window items. Frame decision can considerably have an impact on overall performance. These values characterize double glazing using a 1/two″ air hole.  Yes, https://jasperqdmsz.blogocial.com/secondary-glazing-can-be-fun-for-anyone-70457793