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Understanding Insulation R-Value For Homeowners in Toronto

September 30, 2017

Insulation, whether installed in the attic or basement, is industry rated by R-Value. This is a scale of measurement that specifies “thermal resistance” – in other words, how well an insulating material will hold back heat. In simple terms, the higher the insulation R-Value, the more thermal resistance.

Just by example:

  • A bare concrete wall (basement foundation) rates at an insulation R-Value of about R-1
  • Newly insulated attic rates at an insulation R-Value of R-40 or more.
  • Insulation R-Value is proportional to the insulating material being used. It means that different products require different densities to deliver the same R-Value.

For instance, in order to deliver insulation R-Value of R-30, fiberglass batts would differ in thickness and density than loose-fill insulation or spray foam. Also important to note are the recommended R-Values that should be installed in various part of the home. Reliable industry figures allow for the correct installation. 

Nominal R-Values and Effective R-Values

Nominal R-Values are the so-called “advertised” values, which estimate the performance level of a particular insulating product. Effective R-Values are the actual performance levels, once a product has been installed, and under real life conditions. Here, it’s not uncommon for a product to have an advertised R-Value and perform at a lower level during the cold months of winter.

Unfortunately for homeowners, the difference between estimated performance (the nominal R-Value) and actual performance (the effective R-Value) could be dramatic. Without an insulation expert on hand, homeowners could be in for a surprise. But with the right type of professional advice, insulation products, installation methods, and performance levels can be better defined.

Many variables affect insulation R-Value

Regardless of the product used, insulation material performs differently when installed in an assembly of wood, concrete, or steel. As such, R-Values will also vary. More relevant is air leakage – this can compromise insulation performance, and therefore reduce R-Value. In fact, a poorly sealed attic cavity or basement crawl space can completely throw off insulation performance.

Moisture-laden air is also an enemy of insulation, reducing the effective R-Values measurably. Here again, it’s important that an installation space be totally airtight. Industry professionals insist on airtightness to prevent air movement, block air leakage, and stop moisture from accumulating. All things considered, insulation performance is dependent on many factors.

Professional home insulation with Great Northern Insulation

For the average homeowner, it’s sufficient to understand the basics of R-Values. Project wise, however, it’s important to have a professional contractor managing the installation. Insulation experts have extensive product knowledge, and extensive installation experience. They can assess and interpret R-Values and performance in order to deliver short and long-term benefits.

For homeowners in Toronto, and throughout the Golden Horseshoe, Great Northern Insulation can manage an entire insulation project from start to finish. GNI are professionals in the field, offering homeowners quality products, superior installations, and a satisfaction guarantee. To find out more, call GNI at 1-800-265-1914, or visit the company website at www.gni.ca .

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