To Ventilate or Not to Ventilate

Should attics be ventilated?

There are two correct methods in this case EITHER

• 1. Attics should be highly ventilated.  OR

• 2. Attics should be completely sealed.

Method 1.

• Insulate ceiling and ventilate attic liberally

• Attic ventilation is a very important thing to be aware of as a builder and a homeowner.
• In the winter, an attic that does not properly breathe can have severe moisture problems which lead to roof rot and mold issues. 
• In the summer in an improperly ventilated attic, heats from 130 to 160 degrees are possible. Heats this extreme may conduct from the attic through to the living space no matter how well the attic is insulated.

 

Method 2.

• Insulate roofline with an air barrier and insulation like Air-TIte Spray Foam Insulation. Do not ventilate attic at all. This has several advantages:

• There are no areas where air leakage from the home to the attic could cause condensation or mold.
• In the summer, the attic will naturally keep only 10 degrees warmer then the living space instead of 50 to 70 degrees warmer.  This reduces the load on air conditioning equipment.
• Ductwork that is in the attic will not be as exposed to severe temperature changes which decrease efficiency
• Attic space can be used for temperate storage or living space