Insulation in the home- Wenatchee and Leavenworth Home Inspection

Home Inspector with NCW Home Inspections, LLC

Insulation in the home- Wenatchee and Leavenworth Home Inspection

This is a follow up to my blog on The Scientific Basics of an Insulator.

There are many ways to insulate a home. Fiberglass is the most common but you may want to consider other options. They all have their plusses and minuses.

I am not a big fan of fiberglass for many reasons but it is the industry standard. So here is a list with some information of all the major insulators in no particular order.

The R-value for an insulator is a measure of thermal resistance used in the building and construction industry.

Insulation Comparison 


Cellulose insulation (R-values- 3.0-3.7 + total fill) is made of ground-up, recycled newsprint treated with borate as a fire and pest retardant. Cellulose can be damp- or dry-blown into walls and dry-blown into attics.








Fiberglass insulation (2.2-4.0) has been the industry standard, is made from spun glass fibers, and is available in faced or unfaced batts or loose-fill. Precautions should be taken during installation to avoid contact with skin or inhalation of airborne glass fibers. Traditionally, formaldehyde has been used to bind these glass fibers. Formaldehyde is a volatile organic compound (VOC) that can off-gas potentially irritating or harmful chemicals into a home. Recycled-content and "no added formaldehyde" products are readily available at comparable costs. Listed by National Toxicology Program, Department of Health and Human Services as reasonably anticipated to be a human carcino­gen.





Cotton insulation (3.0-3.7) is available in faced or unfaced batts. It is manufactured from postindustrial recycled content fibers of the textile industry (primarily blue jean factories), with some polyester fiber for strength and "loft." Unlike fiberglass and mineral wool, cotton insulation is not irritating or potentially dangerous to handle. It should be torn, not cut, to fit. Cork and wool insulation are options made from rapidly renewable, natural sources and now available.





Foam BoardFoam board typically has a higher R-value per inch than batt and loose-fill products (e.g., expanded polystyrene, 3.8; extruded polystyrene, 5.0; polyisocyanurate, 5.8-7.0). Well-installed foam board (taped at the seams) creates an improved air barrier. Look for products that use water or pentane as the blowing or foaming agent instead of HCFC, which contributes to ozone layer destruction.





Spray-in FoamSpray-in place foams (3.9-4.3 + total fill) have excellent air-sealing properties, high R-values, and most of them can easily be installed anywhere, including overhead. They are a particularly effective choice for "cathedralized" attics (insulation is installed at the rafters, so the attic is within the thermal envelope. This is a good approach if ductwork is placed in the attic). Most of these foams are low-density, open-cell polyurethane or polyicynene. HCFC-free foam is available, as is soy-based foam. Spray foams are newer in the market, so installers may be hard to find and costs may be high.





Mineral Wool

Mineral wool (2.8-3.7) is produced as batts or loose-fill made from rock wool (from natural rock) or slag wool (an iron ore blast furnace waste product).









Structural insulated panels (SIPs) (4.0 + total fill) consist of rigid expanded polystyrene foam sandwiched between panels of oriented strand board (OSB). SIPs are fabricated off-site, come in thicknesses from 4 to 12 inches, and are fairly interchangeable with wood frame construction if incorporated early in a project's design phase. SIPs advantages include a very high effective Rvalue, excellent soundproofing performance, and rapid on-site installation. Note that mechanical ventilation is typically required when using SIPs due to the resulting airtight nature of such construction. As with foam board and spray foams, look for products fabricated with and from more environmentally friendly foam materials.




Radiant BarrierRadiant Barrier-(little or no R-value) Radiant barrier insulation systems reflect radiant heat energy instead of trying to absorb it. Radiant barriers come in a variety of forms, including reflective foil, reflective metal roof shingles, reflective laminated roof sheathing, and even reflective chips, which can be applied over loose-fill insulation. The reflective material, usually aluminum, is applied to one or both sides of a number of substrate materials. Substrate materials include kraft paper, plastic films, cardboard, oriented strand board, and air infiltration barrier material. Some products are fiber-reinforced to increase the durability and ease of handling.

Radiant barriers-which don't provide a significant amount of thermal insulation-can be combined with many types of insulation materials. These combinations are called reflective insulation systems. In these combinations, radiant barriers can also act as the insulation's facing material.



Recycled Content (environmental comparisons)

Insulation materials vary in their recycled content.  Which insulation offers the environmental benefits of resource conservation and reduced waste? The typical recycled content of various insulations is as follows:

Fiberglass: 0-30%, mostly post-industrial, some post-consumer

Cellulose: 75-95%, mostly newspapers

Mineral wool: 0-90%, rock wool - 0%, slag - 90%

Cotton: 75-95%, post-industrial fabric trimmings

Foam board: 0-50%, post-industrial foam

Spray foam: 0-15%, post-industrial chemicals

Radiant Barriers: 0-100%, mostly recycled aluminum

Insulation in the home- Wenatchee and Leavenworth Home Inspection

NCW Home Inspections, LLC  is located in Wenatchee Washington serving Chelan County, Douglas County, Kittitas County, Okanogan County and Grant County Washington and the cities of Wenatchee, Leavenworth, Cashmere, Orville, Cle Elum, East Wenatchee, Quincy and many more...                             

NCW Home Inspections LLC-509-670-9572


Re-Blogged 2 times:

Re-Blogged By Re-Blogged At
  1. Dan Edward Phillips 07/05/2011 08:33 AM
  2. Dan Edward Phillips 08/22/2011 01:34 AM
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Not a real person
San Diego, CA

Just stopped by to say that I

Happy Fourth of July!

Jul 04, 2011 06:53 AM #1
Donald Hester
NCW Home Inspections, LLC - Wenatchee, WA
NCW Home Inspections, LLC


Thank you and you have a very happy and safe 4h.

Jul 04, 2011 07:25 AM #2
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