When I remodeled this 1450' house and retro fitted a heat pump (electric baseboard before) I took off all the old 1960 siding and shiplap and redid the insulation from the outside in doubling what had been in there to R13. This house was built in '60 as a "good cents" house ala' PGE when electricity was really cheap and hey, insulation is expensive....... I made dang sure we have R35 or higher in the overhead, too. Finished off the outside with ply, felt, then hardiplank siding all around. Took a spell but we got'er done. New Milgard double pane windows at the same time as I went around the house on the siding. Been MUCH warmer and happier since! I'm freezing in 70* in winter and yet 70* in summer is comfy...go figure.