Diane writes from Barnwell, South Carolina: "My house is over 100 years old. It has 11 foot ceilings and no insulation in the attic. We will be insulating soon but thought we'd ask the expert first... We're in the hot, humid south. Where would you recommend starting? I heard that one should lay the insulation with the paper side down (or up?) and possibly add another roll of insulation on top of the first roll except in the other direction. Is this true and can you elaborate? Thanks!"

Thank you for the question, Diane. We would start in the attic, where you are apparently preparing to start. If you are using two layers of insulation, the second should be placed across the first layer at a 90 degree angle, as you also indicate.

In high humidity areas the local building code will indicate which way the vapor barrier should face. Sometimes in your part of the country they do not use a vapor barrier and sometimes they want the vapor barrier to face the outside.

Check with your local building code for the correct method in your area.