Ask The Inspector - Adding Insulation to Older Home

Question:

We've added insulation to the attic in our older home but wonder if adding a radiant barrier would help with heating and cooling bills?  

Answer:

Radiant barrier can help in controlling your heating and cooling costs if properly installed.  Here are some of the types that you can purchase.

To be classified as a radiant barrier the Department of Energy states that products must have a reflectance of 90 percent and an emissivity rating of no more than 10%.  Here are some types.

* Foil Backed Insulation.  A foil barrier is made of a thin layer of aluminum laminated to a thin layer of substrate. This substrate can be craft paper, cardboard, plastic sheeting, etc. The barrier may have aluminum on one or both sides and is typically installed inside the attic.

* Radiant Barrier Chips. These are small pieces of aluminum coated materials that are installed on the insulation on the floor of the attic space. The chips are layered on top of the insulation about 1/2-inch thick and are intended to reflect the heat from the sun before it reaches the insulation layer.

* Roof Sheathing.  The plywood used as a platform for roof shingles can also have an aluminum radiant barrier coating applied to it. This type of radiant barrier is used primarily in new roof installations or replacements as the felt and shingles will have to be replaced on top of the sheathing.

* Low Emissivity Paint.  Not an actual radiant barrier, low emissivity paint is applied to the exposed areas in the attic, and the un

Source: Fox Inspection Group