Lynne writes again from Clinton, Ohio and sends a drawing: "Here is what the room looks like in comparison to the roof. There are knee walls with storage areas behind them."

Answer: A minimum of R-38 is recommended in the ceiling of the room you are insulating, with R-13 on the knee walls. Install more R-38 on the floor behind the knee walls. Be sure to maintain at least one inch of airflow along the entire roof line. The ceilings behind the knee walls do not need to be insulated.