Why Do I Need Insulation?
Next to proper air sealing, insulation is arguably the most important feature that contributes to your comfort and your home’s overall energy efficiency. Without proper insulation, your home needs larger, more expensive heating and cooling devices to keep you comfortable and those devices need to work harder, consuming more electricity, gas, or oil and costing you money.
Consider this. On a cold winter night, would you rather have a thick, puffy down-filled blanket or a single thin cotton sheet on your bed to keep you warm? Think of insulation as the blanket for your home.
Where is Insulation Located and How Much Do I Need?
Ideally, insulation surrounds the living area of your home forming a barrier between the living area and outdoor temperature extremes. In the energy efficiency field this is often referred to as the “building envelop”. Understanding where these barriers are (and are not) in your home and whether those barriers are sufficient is one of the top jobs of an energy auditor. Temperatures permitting, energy auditors use an infrared camera to “see into” your home to identify those areas that have no or insufficient insulation.
R-value is a measure of a material’s ability to resist heat flow. The higher the R-value, the more effective that material is at preventing heat loss from your home in the winter and heat gain in the summer. In general, you should have insulation in the following areas of your home. Recommended R-Values are for Western Pennsylvania referenced from
NAIMA:
- Attic and Cathedral Ceilings: R38-60
- Exterior Walls: R13-15
- Floors over Garages, Crawlspaces or Unheated Basements: R25-30
An energy auditor can identify additional areas of your home where insulation is appropriate.
What Type Insulation Should I Use?
The type of insulation you use depends on a number of factors including:
- Material Cost
- Labor Cost
- Accessibility of the Area to be Insulated
- Material Characteristics
Fiberglass Batts are typically used in new construction and in areas that are easily accessible, such as an attic.
Blown-in Cellulose (recycled/treated paper) is ideal for closed wall cavities and atop existing attic insulation.
Foam Panels are ideal as exterior building sheathing and within the band joists of your basement.
Spray or Injected Foam is ideal to fill around plumbing and electrical penetrations and band joists. Spray Foam is doubly effective as an air-sealer in these applications.