What type and where should I use insulation ?

Many different types of insulation can be used in a re-model or new construction. Most have similar R-values/inch but, there are other differentiating characteristics.

In PDR we used Icynene, Cellulose, Formaledhyde-Free Fiberglass in the walls, ceiling and floor (and a few interior walls), respectively. In addition, I sealed all gaps and penetrations with a 30-year caulk to limit heat loss from the interior of the house to the attic. It is also important to talk about  heat loss through windows and doors since a substantial surface area of the walls will be covered by windows and doors.  To create a an effective building envelope it is critical to have energy efficient windows and doors as well as  good weather stripping around doors.

California's Title 24 Standard mandates a minimum energy efficiency for compliance.  In similar climates (Zone 24),  shoot for the following R-values or better:

• R-30 in attics
• R-13 in 2X4 walls,  R-19 in 2X6 walls
• R-19 under the floor
  

You will need to decide how healthy and sustainable of a material you want to use  for the cost. Equally important is how effective the installation method is:   

• Loose-fill
• Blown-in (wet)
• Batts
• Rigid panel 

As I mentioned, I did not want to risk a poor fiber-glass batt installation in my walls.  So, while fiberglass batts are the cheapest and you can get them formaldehyde free there are a lot of other alternatives. Natural cotton fiber  made from recycled blue jeans, straw bales, SIPs, insulating masonry are other insulation examples.

What is Icynene ?

Icynene is an open cell Polyisocyanate.   It is water-blown for installation, 99% air and 1 % material. It stops air infiltration while allowing water vapor  to permeate, it is non-nutritive to rodents/mold, won't sag or loose its R-value over time, contains no formaldehyde nor VOCs.  Convective air movement inside cavities is virtually eliminated.
 

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