I purchased an early 60's home in a cold climate (northern canada) with an unfinished basement. It was renovated in the 90's, to a vinyl siding with 1" polystyrene underneath. The interior walls are plaster board over 1/2" gypsum (no, really), and, at best, 2" faced batts on exterior walls. There is ~4 feet of uninsulated concrete above grade. We are looking to redo the exterior in the spring to a 2" polystyrene, house wrap, new vinyl, as well as extending the polystyrene down the concrete to 24" below grade with parging or something similar overtop. One 'unique' feature of this house is that the floor joists are set directly into the concrete. This house is cold. I mean, it's really cold. And it hasn't even gotten cold yet. I am looking for advice on how to temporarily keep (at least some) cold at bay. We have already added 6" of Roxul R22 to the attic for a total of 12" up there. I have not laid insulation batts across the centre beam of the attic. We have removed the old oil burning monstrosity of a furnace and installed a HE gas furnace, but it seems to kick on all the time, even though it's barely below freezing at the moment. - should I add batts on the attic beam? - should I insulate the 4' of exposed concrete from the outside with polystyrene and tuck tape it, knowing I can't excavate/seal/parge it correctly until the spring? - should I insulate interior basement walls? My local building code recommends tar paper, spacer, stud wall with insulation, and vapour barrier. - should I remove interior plaster/drywall and re-insulate? - should I do something that I haven't thought of? I have many options, I'm just trying to weight the best long term one, ie., least waste, most impact. I'm not sure if my neighbours would appreciate seeing 4' of pink or blue staring at them all winter, but to be honest, I'd rather be warm than thought well of in the short term.