New Construction in Elizabethtown So, you have your dream house plans completed and ready for construction? Did you think about what will condition your house? Why not consider the most economical heating and cooling units on the market. Your recently built house represents your pride of ownership and only the finest will do. By adding a WaterFurnace geothermal system in your Elizabethtown home, you include your heating and cooling system in that feeling of new home ownership as well.