Improving home insulation for savings and comfort: Part 2

Choosing the correct type and form of insulation depends on several factors and can save the homeowner money and improve comfort in winter and summer.

According to the U.S. Department of Energy, the average American spends 44 percent of the energy used in the home on heating and cooling. 

Home insulation has become so important that having the correct amount in the correct places is not an option anymore.  With the increasing cost of non-renewable energy, it is a necessity.  If your home is more than 15 years old, it may be time to evaluate your insulation needs to see if there is enough. 

The three factors in choosing the best type of insulation are

  • Where you want or need to install or add insulation
  • The R-value you want to achieve in the home or area
  • Who will be installing the insulation

Other considerations might include indoor air quality impacts, life cycle costs (will cost of installation be recouped in reasonable time), recycled content of insulation and ease of installation.  Remember that the R-value is very dependent on correct installation of whatever type you choose.

There are a variety of insulation materials from blanket batts and rolls to radiant barriers.  They all have advantages and disadvantages to consider when choosing. Not all types of insulation require a professional while others should only be installed by a professional. The most common types of insulation are:

Blanket: Batt and Roll insulation:

  • Most common and widely used type
  • Consists of flexible fibers, usually fiberglass or recycled plastic
  • Comes in widths to accommodate standard wall stud, attic truss or rafter spacing
  • Available with or without facing which acts as a vapor barrier
  • Unfaced batts are better when adding additional insulation over existing insulation
  • Comes in standard, medium and high density products which affects R-value and is typically R-11 for standard to R-15 for high density
  • Good for do-it-yourself projects 

Foam Board or Rigid Foam:

  • Good for any place in the home
  • High insulation value based on thickness
  • Made from polystyrene, polyisocyanurate, polyurethane or fiberglass
  • R-value of R-5.6 to R-8 per inch
  • Good for do-it-yourself projects 

Loose-Fill or Blown-In Insulation:

  • Consists of small particles of fiber, foam or other material, such as cellulose, fiberglass, mineral wool 
  • Primarily made from recycled material; example: cellulose is made primarily of recycled newsprint
  • Conforms to any space without disturbing structure or finishes so is good for retrofit projects
  • Cellulose, fiberglass and rock wool should be installed by professionals to get correct density and R-value
  • R-value per inch of R-2.2 for fiberglass to R-3.8 for cellulose 

Radiant Barriers and Reflective Insulation:

  • Work by reflecting heat away from the living space
  • Most often used in attics to reduce summer heat
  • Most effective in hot climates
  • Not as effective as installing additional thermal insulation
  • No R-value rating because reflects heat rather than restrict heat flow 

Rigid Fiber Board Insulation:

  • Primarily used for insulating air ducts in the home
  • Made either of fiberglass or mineral wool material
  • Most often installed by HVAC professionals
  • R-value of R-4 per inch of thickness 

Sprayed-In and Foam-in-Place Insulation:

  • Liquid material that is sprayed, injected or poured in where it hardens
  • Conforms to irregular, small areas to prevent heat flow
  • R-value per inch may be twice that of traditional batt or roll insulation
  • Does not contain chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs)
  • Needs special equipment and should be done by experienced installers 

For more information on home insulation, see the Michigan State University Extension bulletin Home Maintenance and Improvement: Insulation. The U.S. Department of Energy has a variety of information on insulation as well.  

Part Three of this series will cover Determining Insulation Needs. 

Other articles in this series

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