New Construction in Grinnell 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 dynamic heating and cooling units on the market. Your newly built house represents your pride of ownership and only the highest quality will do. By installing a WaterFurnace geothermal system in your Grinnell home, you include your heating and cooling system in that feeling of new home ownership as well.