subject: Is It Possible To Evenly Cool A Multi-Level Home? [print this page] As for environmental concerns, it seems that keeping a multi-level home at the right temperature requires a lot of energy inefficient tricks. This doesn't have to be the case. For starters, make sure you have a highly efficient furnace with a variable speed option. Even a furnace running at 80 percent has a much worse impact on the environment and on your checkbook.