We heat our 3400 sq ft center hall colonial, built 1795, with 2 pellet stoves, one at each end of the house. The kitchen has a Mt Vernon AE that pretty much runs 24/7. In the living room, a Harman Accentra insert installed in the fireplace. We have insulated the acttic but not the walls. The basement is air sealed and interior storms on 21 windows. The downstairs is maintained at 68-70F and upstairs 60-65F even during this brutal New England winter. We use no oil except as backup and burn 7 tons during an average winter. In the past we needed over1500 gals of heating oil for the season and were never as comfortable. With heating oil still over $3 per gallon in Vermont, we are saving over $3000 per year. Hope this helps.