or should the topic be stairBAD insulation - i have an old colonial 3 story house (2 floors with walk up attic).  I just realised the large stairwell from basement to attic has no insulation (nor could it really) between attic and lower floors and other than stair treads, stringers and drywall is a huge hole in the building envelope.  Another reason the whole house should be sealed, including the attic.  I guess you could try to put some foam board between the drywall and the bottom of the stairs up to the attic, but it would be almost impossible to get a good seal throughout.  Anyone ever try to address this issue?