What do you call single pane glass window with a removal interior glass pane for cleaning? home built in 1988.
That appears to either a single hung or double hung. If it is the pane you are asking about and they are Pella, it is a DGP.
got it, that’s what I was looking for (dual glazing panel) thay are double hung
Nope “detachable glazed panel”
These generally had a film for tint and or reflection. Early model for low-e