Maintaining heat during the cold weather

Where I live, there are bad Winter seasons. We all get numerous feet of snow and suffer from a lot of Winter storms. I live in an older farm home which is great other than the fact that the Winter seasons are cold and drafty. We have very little insulation since the home is so ancient. In our room especially, I can feel the crisp breeze seep in through our walls. I have asked our father numerous times to repair the insulation concerns and explained how it would save him a ton of money on weekly bills, however he is too stubborn. He thinks that our new gas furnace is enough to maintain the heat in our home during the Winter season. He doesn’t realize how much of that heat is being wasted from so little insulation. We have a boiler system that we use to heat the home. While several other houses have a central gas furnace that seems to push more heated air into the environment. We get our entire HVAC system cleaned and took care of in the beginning of every Winter season. Regardless of how well we maintain it  it does not make up for the lack of heat throughout the Winter season. We have taken many smaller steps to help keep the heat inside. For example, we all have insulated curtains for our rooms and we lay towels in front of the doors to make sure the draft doesn’t disrupt the gas furnace. But it never fails to keep our furnace running all day and all night long. If our father would listen, we could find a better gas furnace that suites our beach house and saves us some money.