For a home to be truly energy-efficient and cost-effective, proper attic insulation is the first place to consider. Heat rises and escapes through cracks and gaps in the roofing system during the cold months and that cold comes in through the same gaps during the hotter months.
If your utility bill is high, it is likely that the attic is not properly insulated. You can spot check if you need more insulation in the attic by looking across the attic’s area span. If you see any joists, then your attic is gravely under insulated. Today’s standards are 16” depth of insulation. Proper insulation will make the attic air-tight, well-ventilated and moisture and condensation free.
Types of Insulation for the Attic
Here are a few common methods and materials for insulating attics.
Batts and Rolls are rolled out across the joists. Find insulating material that is 23” wide. A DIY-er can insulate his own attic by rolling the insulation between the joists. This type is also known as blanket insulation. This is a difficult way to insulate an attic.
Loose-fill Insulation is best insulating attics. Loose-fill material such as fiberglass, rock wool or cellulose is blown into the area by the use of an insulation blower. The material is sprayed on the whole span of the attic including the gaps and cracks. Rulers are placed at different places in the attic to help the insulator judge the depth correctly and to spray evenly.
Reflective Insulation is common in the Southern states. Foil insulation is stapled to the ceiling of the attic.
It is best to have a professional weatherization contractor to assess the attic to know which type of insulation and R-value it requires to be effectively air-tight.