R-Value: Why is it so important?

Thursday, June 27th, 2019 by Alaina Marra

R-value is one of the most important concepts for you, the homeowner, to understand when insulating your home, upgrading windows, and doing any sort of renovation on your home. “R” is a variable that communicates the capacity of an insulating material to resist heat value. The higher the R-valued, the greater the insulating power. It should be simple, but it is commonly misunderstood as an isolated value, when, the given R-value and the actual performance of an insulation in your home can be very different.

What is R-Value and why is it important to know about it? - Image 1Insulation products are typically explained by their R-value per one inch. For example, 1” of solid wood has an R-value of 1.0, 1” of fiberglass batting has an R-value of 3.1-3.4, 1” of blown cellulose has an R-value of 3.2-3.7, and 1” of closed cell spray foam is an R-value of 6.0-6.5. The R-value of the actual walls, floors, roof, etc. are the calculated total of all the building elements’ insulating values. For example, a common exterior wall can be made up of vinyl exterior siding (R-0.6), a vapor barrier sheet, a 1” layer of plywood (R-1.25), a 1” airtight air space (R-1.0), 4” of fiberglass batts (R-12.4), wires and such, and finally ½” sheets of gypsum wall boards (R-0.45). This wall totals to an R-value of 15.7. A typical wall cavity in Connecticut should have an R-value of R-13 to R-21. R-15.7 is okay compared to the recommended amount but is incredibly above average to most homes and shows there is a lot of room for improvement upon typical building practices.

Any contractor can list off high R-values for types of insulation deeming they can give you a more energy efficient and comfortable home, but the truth is, it all depends on the correct insulation installed correctly in the correct places. A contractor can promise you that R-15.7 wall, but tests show that with the “worst case commonly found procedures for installing batt insulation” the performance drops to R-11. This is not acceptable.

What is R-Value and why is it important to know about it? - Image 2

The proposed R-value fiberglass batts manufacturers claim are accurate, but incredibly misleading. This is because the material’s ability to insulate is tested under very isolated, airtight, and controlled conditions. They are installed fully fluffed in an airtight box with no leftover air space inside. They are place on a 75-degree F plate in an isolated environment with no air flow and the amount of heat it allows to radiate through is measured. However, these conditions are impossible to achieve in a home due to wire holes, air gaps, moisture and other miscellaneous reasons. Fiberglass does not insulate as effectively when installed incorrectly. It can lose effectiveness depending on temperature, aging and moisture accumulation. Mistakes commonly found in their installation include them not being fully fluffed, placed in open air conditions, ill fit within joists, and installed against a foundation wall. These can all leave you with an energy inefficient, unhealthy and uncomfortable home. 

What is R-Value and why is it important to know about it? - Image 3

Dr. Energy Saver of Connecticut chooses not to install fiberglass batts insulation and recommends most foam based, treated cellulose, or inorganic insulation materials. This allows us to avoid the common mistakes and any moisture or aging in materials. We always air seal any gaps in attics with expanding spray foam, then install blown-in Cellulose insulation where we typically recommend reaching anywhere between R-35 to R-60 of insulation. We can also install our SilverGlo rigid foam insulation that gives your walls a consistent, unbroken plane of R-11 insulation and can use our Spray Foam in other cases that can give R-6.2 per inch of insulation creating an effective thermal and moisture barrier. To learn more about our home insulation services click here.

What is R-Value and why is it important to know about it? - Image 4

R-value at the end of the day is subjective, it is only relevant to your home’s construction when you have a trusted contractor doing the work. Dr. Energy Saver of Connecticut has a strong reputation for our well trained and experienced installation specialists. Our company was founded on pushing typical construction methods to the limit and committing years of research into developing the best of the best, innovative products. Our company is proud to be installing our cutting-edge insulating products that have contributed to the home contracting industry’s most recent push for increased home energy efficiency to make our planet healthier.

Looking to make your home healthier and energy efficient? Dr. Energy Saver of Connecticut can help! Contact us at 800-328-1081 or click here for your free at home estimate!





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