Modern heat pumps are great in spaces that are insulated well. Even when very cold outside they can get enough into the space to keep it warm. In spaces with po

Modern heat pumps are great in spaces that are insulated well. Even when very cold outside they can get enough into the space to keep it warm. In spaces with poor insulation then a furnace or boiler is better as they can blast a space full of heat quickly. In my very old home I have areas that are not insulated and a furnace heats them. I have had renovations and those areas are well insulated and a heat pump does great.