By Patrick Keegan and Amy Wheeless
My neighbor added more insulation to his attic this summer. How can I tell if adding more insulation in my attic would be a good idea, too?
When your home is not properly sealed and insulated, cold air sneaks in and heat escapes, making your heating system work harder and your home less comfortable. Sealing and insulating your home to efficient levels can cut your heating and cooling costs by an average of 15 percent — all while making you more comfortable in your home.
Your attic is one of the first places you should consider adding insulation since it is usually accessible and easy to inspect for air leaks and insulation levels. Additionally, most homes do not have enough attic insulation. Insulation standards for new homes increased in 2012, and many homes built before then do not have the current recommended amount of attic insulation.
Insulation is graded by its “R-value” — the higher the R-value, the greater the insulating power. For all of Indiana, R-49 is the minimum recommendation, or about 16-18 inches of insulation. More may be needed depending on your home and exact climate.
How can you tell if your attic is lacking in insulation? As a general rule, if you go into your attic and can see the ceiling joists on the attic floor, there is not enough insulation. Hiring a trained energy auditor is the best way to diagnose shortcomings with insulation or any other energy-related issue. Check with your electric co-op to see if it offers energy audits or can refer you to a local energy auditor.
Once you have determined that you need more insulation in your attic, there are a few things you can do before laying it down:
• If you store items like holiday decorations in your attic, consider another storage location. If you must use your attic, build a platform high enough to allow the recommended level of insulation.
• If you live in an older home, you should check your attic’s electric wiring. Is the insulation around the wires degrading or is the wiring outdated? If so, you will want to replace the wiring before proceeding.
You will then need to decide who will do the insulation work. If a “DIY” project interests you, you’ll need to do some homework. Installing insulation is messy, potentially dangerous and requires special equipment. Fortunately, there are many experienced insulation contractors. You should discuss a few things with the contractor before you hire them:
• Be sure that you or your contractor seals any air leaks, such as around furnace flues and around any exposed air ducts in the attic. Air leaks can bring warm, moist air from your home into the attic, which can reduce the insulation value and create mold.
• Pay particular attention to your attic door or hatch. This entry point is a significant contributor to heat loss and heat gain in the home.
• If you have existing attic insulation, it is usually not necessary to remove it unless it is wet, moldy or contains animal waste.
• Make sure there is sufficient ventilation in the attic. Warmth and moisture can build up in an improperly ventilated attic, which can lead to roof problems, such as roof rot or ice dams.
There are two types of insulation that you could place on your attic floor: batt/roll or blown-in/loose fill. Blown-in insulation requires special equipment to install, but it fills the space better than batt insulation, which can leave gaps and voids without careful cutting and placement around ceiling joists, vents and other attic impediments.
Insulation is most commonly made from fiberglass, cellulose or mineral wool. Many energy advisors recommend blown-in cellulose insulation due to its superior coverage, high R-value and air sealing abilities; blown-in cellulose insulation is treated with boric acid, which acts as a fire retardant and insect repellent.
Patrick Keegan writes on consumer and cooperative affairs for the National Rural Electric Cooperative Association, service arm of the nation’s 900-plus consumer-owned, not-for-profit electric cooperatives based in Arlington, Virginia. Amy Wheeless writes for Collaborative Efficiency. For more information, visit:www.collaborativeefficiency.com/energytips or email Pat Keegan at energytips@collaborativeefficiency.com.