Well I stand corrected...my AF 1150 has a single pane of tinted glass...definitely not two panes (dual pane). The confusing part is my windows are configured with the horizontal, sliding windows described in insp1505's reply. I guess I correctly have 'storm windows' although I can't find that option or description listed on the Northwood site. So I'm not sure now if the Northwood option of 'thermal pane windows' are true dual panes or if that is their description of removeable 'storm windows' like I have. I'm curious for those that have the true dual panes if they also came with the removeable storms?!?
