Insulating R-Values: the Reason They Vary More Than You Think
R-value is a measurement of heat resistance given to insulating material. A higher R-value means better insulation, overall, and more energy savings. However, the number you’ll find stamped on the side of the insulation you’re purchasing is not as cut and dry as you would think.
What You See Is Not Always What You Get
The actual performance of insulation varies, depending on circumstance. One major factor is how the insulation was installed; the R-value posted on the packaging only applies if the insulation is being used correctly. For example, for insulating products that are applied by spraying, giving the application area a quick pass isn’t going to do the job. It needs to be a certain thickness to perform correctly; three to four inches is usually enough.
Another factor is the temperature itself. Most kinds of insulation actually work better as it gets colder outside. For example, fiberglass batt, normally rated at R13, actually performs more like R14 at 10 degrees. Similarly, the rating falls a bit as the weather gets hotter. It rates at nearly R12 if it’s a steamy 95 degrees outside. Extruded polystyrene (XPS), which is a rigid foam board, and expanded polystyrene (EPS), which is the sprayed foam mentioned above, also behave this way. However, polyiso, another foam board, loses performance as the thermometer drops to under 30 degrees. Adding more than the prescribed amount of inches of polyiso will counteract this issue.
Getting the Most Out of Insulation
In Ohio, where the temperature can easily dip below 20 degrees in the winter, it is essential to have adequate insulation to properly heat a home while keeping energy costs down. Cincinnati homeowners should aim for enough insulation to achieve an R-value between R38 and R49, according to Energy Star.
To learn more about R-Values and how they affect your home, as well as other information about home comfort, please contact Apollo Home Heating, Cooling and Plumbing. Our family has been proudly serving the Greater Cincinnati, Ohio area for more than 100 years.
Image via Shutterstock.com