Home Inspection Insulation
Insulation in your home provides resistance to heat flow and lowers your heating and cooling costs. Properly insulating your home not only reduces heating and cooling costs, but also improves comfort. Insulation slows down heat flow, which involves three basic mechanisms — conduction, convection, and radiation. Conduction is the way heat moves through materials, such as when a spoon placed in a hot cup of coffee conducts heat through its handle to your hand. Convection is the way heat circulates through liquids and gases, and is why lighter, warmer air rises, and cooler, denser air sinks in your home. Radiant heat travels in a straight line and heats anything solid in its path that absorbs its energy.
Home Insulation Materials
There are four main types of insulation materials on the market today used for attics and wall cavities: fiberglass, rock wool or slag wool, cellulose, and spray foam. Each of these options has different qualities and attributes that may inform your choice of materials. The four main types of insulation used in residential homes is Rolls and Batts, Loose Fill Insulation, Rigid Foam Insulation and Spray Foam insulation. Choosing the right type of insulation will depend on your budget and area of installation. Read about Asbestos Testing for your Home
R-Value of Insulation – R value measures the resistance of heat transfer from one side of an object to another. For example, one inch of solid wood has an R value of 1. In comparison, an inch of blown fiberglass insulation has an R value of 3.1 – 3.4, and an inch of closed cell spray foam insulation has an R value of 6. R value is an indicator of how well insulated your building is. It refers to the ability for a material to resist heat loss. Said differently, the higher the R value, the greater the resistance, and better insulation power.
Types of Insulation
Rolls and Batt Insulation
Batt insulation is a very common type of insulation and it comes already pre-cut. The main material used for batt insulation is fiberglass but you can find it made out of foam and even wool and rock. When installing roll insulation you’ll need to cut the insulation to the proper length with a utility knife; forcing the insulation to fit by compression makes it less effective. Some manufactures provide a backing attached to the insulation to act as vapour barrier or air barrier.
Loose Fill Insulation
Typically blown-in insulation is made of either cellulose or fiberglass. The material is shredded and blown into place, densely packing the area the entire area with insulation. The result is literally a blanket of insulation that shields your home from the outside environment. Cellulose is the most eco-friendly choice when it comes to blown-in insulation. It is manufactured with recycled paper, and it is treated to resist fire. Fiberglass is also eco-friendly, but it contains more new materials than cellulose. It is manufactured with recycled glass, and it is naturally fire resistant.
During the many home inspections I have done one item stands out about using cellulose insulation in your attic, mice do not like it. Mice do love fiberglass insulation and almost every home I inspect has an attic full of mouse trails and holes in the insulation. Mice can walk up a brick wall and have the ability to compact their head allowing them to access most soffit and brick joints.
Rigid Foam Insulation
Rigid foam board insulation excels in below-grade applications such as basements as it does not absorb moisture and its smooth surface resists mould. Usually you would not install fiberglass insulation below-grade, since fiberglass soaks up moisture. Rigid foam board insulation excels in below-grade applications such as basements. Rigid foam board insulation comes in up to 4-foot by 8-foot sheets to help you rapidly cover expansive walls. Smaller and more manageable 2-foot by 8-foot and 4-foot by 4-foot sheets can sometimes be purchased. The majority of foam insulation cannot be exposed anywhere within the building envelope of a home. The Ontario Building Code lists many products that may be used as a thermal barrier.
Spray Foam Insulation
Spray foam insulation and insulating foam sealants are made by mixing and reacting unique liquid components. The liquids react very quickly when mixed and applied on site, expanding on contact to create foam that insulates, seals gaps, and can form air, moisture, and vapor barriers.
Open cell foam has a higher possibility of absorbing water than closed cell foam, which can lead to degraded performance, especially for thermal applications. While engineers do not necessarily strive for perfect vapor impermeability, the free flow of water can be detrimental to a structure and can trap water.
HIGH-DENSITY |
MEDIUM-DENSITY |
LOW-DENSITY |
| lbs./cubic ft., closed-cell foam | 2 lbs./cubic ft., closed-cell foam | 0.5 lbs./cubic ft., open-cell foam |
| R-Values start at 5.5 per inch* | R-Values start at 5.7 per inch* | R-Values start at 3.6 per inch* |
| Often used for exterior and roofing applications |
Often used for continuous insulation, interior wall cavity fill, and unvented attic applications | Often used for interior wall cavity fill and unvented attic applications |
The Ontario Building Code requires foam insulation products to be protected with a 15 minute thermal barrier if they are inside the building envelope. This includes foam board, spray foam, ICF blocks and any other “foamed plastic” products.
Most spray foam installers left a information label at a conspicuous place like on the electrical panel. This identifies product and type.
Vermiculite Insulation
Vermiculite is a mineral (hydrated laminar magnesium-aluminum-iron silicates or hydrated phlogopite or biotite mica) from the phyllosilicate group. Vermiculite looks somewhat like mica in that it includes shiny flat plates of material that can be separated. Because this mineral expands to many times its original volume when it is heated, processed vermiculite produces a lightweight material with insulating and other useful properties. Vermiculite is also fireproof (non-combustible), pH neutral, and is non-reactive to any but the strongest acids.
Vermiculite is a mineral that was used for insulation. If your home was built before 1990, you might have vermiculite insulation in your walls or attic. Up to 85 percent of all vermiculite insulation in the U.S. came from a mine in Libby, Montana, sold under the name Zonolite.
Asbestos of the type used in vermiculite insulation was banned in Ontario in 1985. However vermiculite insulation was widely used in Canada in the 1950s, 60s, and 70s.
Vermiculite Testing for Asbestos
The Wasaga Beach Home Inspector provides Asbestos Testing Services from a Certifed Laboratory. Fee for a single sample test is $120.00 and the results typically take 4 to 5 days for a full report.
Call Roger Frost for further information or any Questions you may have regarding your home. 705-795-8255