How Many Inches of Insulation Should be in My Attic?

Homeowners frequently ask how much attic insulation they need. If you consider upgrading the insulation on your attic, several considerations will determine how many inches you need. When ready for an attic insulation project in Austin, be sure to hire professionals who can assess your unique situation, offer excellent advice and provide reputable services. 

The inches of insulation you require will depend on several factors, including the house’s location and when it was built. Each climate zone is suited to different types and amounts of insulation. Most homes built before 2007 are considered under-insulated according to modern standards. Read on to find out more about the appropriate amount of insulation in the attic. This list will help clear up any confusion on the inches of insulation you need in your attic. 

Does Your Attic Need Extra Insulation?

If you built your house within the last five years, the chances are that the insulation would still be holding up. Approximately 90% of the homes in America are underinsulated. Under-insulating the attic can cost homeowners dearly because it increases energy bills by allowing heat leakage during cold months. It is estimated that proper insulation can save you 10% to 50% on heating costs every cold season. 

Common signs that need extra insulation are high energy bills, draftiness, and difficulty achieving the desired internal temperature. R-value is used to measure insulation, and it essentially considers the thickness and effectiveness of the insulation material. The best R-value for your home will depend on the location and age of your home. R-value measures an insulation material’s ability to resist heat flow. The bigger the R-value, the better the insulation’s thermal performance. 

The United States Department of Energy recommends that homes in the South be insulated with R-38 (13 – 14 inches) at minimum. The recommended value for Northern homes is R-49 (16 – 18 inches) of insulation at a minimum. You only need to find out how much insulation your attic has is a ruler. 

How Much Insulation Do You Currently Have?

The first step to figuring out how much insulation you need is checking out how much insulation you have now. You can use a ruler to measure the depth of the insulation in inches. Make sure you measure from the floor to the top of the fill. If the space between your joists is filled, there is still a chance that your home isn’t adequately insulated. Most joists are approximately seven inches tall. Even when filled, they only provide insulation at R-21. 

If your attic is underinsulated, you will need to add extra insulating material for a higher R-value to ensure your attic is well insulated. If your floor joists are fully covered with insulation but your home is still drafty or not reaching the temperature you’d like, chances are you may have the wrong kind of insulation or an air leak. 

Which Climate Zone Do You Live In?

The United States Department of Energy provides insulation recommendations for different climatic zones. The minimum recommended insulation amounts vary greatly even within the same state. They also have an insulation calculator on their website that lets you get a customized recommendation for the appropriate amount of insulation for your attic. You can also find the specific Residential Prescriptive Requirements for your state and county on the energy code website.

What Kind of Insulation Material Are You Adding? 

How many inches of insulation you will need to add will depend on the type of insulation material you select. You do not have to use the same kind of insulation material currently installed in your attic. For the best advice and superior services, consult a qualified technician. You can opt to add loose fill on top of blankets or fiberglass batts and vice versa. When using fiberglass over loose fill, it is essential to ensure that the fiberglass batt is unfaced (does not have paper or foil backing). 

There isn’t a single answer for how many inches of insulation is required for your attic because this depends on the type of insulation you currently have, how well-sealed your home is, your geographical location, and your heating and cooling goals. The best way to determine the most appropriate insulation for your home is by relying on a qualified technician. A reputable professional will be able to assess your current insulation and recommend efficient alternatives. Check out the review for your local HVAC and insulation specialists to ensure you pick out the best one.