A dual pane window with low-e coating and frame which is not aluminum or steel will have the energy star rating
if it has a low-e coating. The tax form states:
“Special rule for Energy Star
windows and skylights: You
may rely upon the energy Star label that identifies any window or skylight as an eligible building envelope component rather
than the manufacturer’s certification.”
Since the risk of being audit is slight, a spurious claim will probably go unnoticed. Save one energy
star sticker, to prove that the windows were so rated. Also a copy of the contract showing.