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Georgia Power Home Improvement Energy Rebates

Southface

Building Performance Institute

Energy Star

Insulation in a Home

Almost all modern homes have too little insulation and the comfort of your home is more dependent on insulation than anything else. Attic insulation is the most important area in a house because of the 140 degree temperatures that are reached in attics during the summer. Most homeowners rarely go into their attics and that's why we take a lot of pictures during our audit.

R value is the measure of thermal resistance to heat flow, a larger R value number will slow down heat flow more. At the bottom of the page are two tables one with the recommended minimum R values for the different areas in a house and the other table shows the R values of different insulating materials.

When we inspect an attic we almost always find insufficient insulation. Cellulose tends to settle over time, pieces fall out of place and there's usually an area or two that were never insulated at all or incorrectly. For our Georgia Power customers there is a $200 rebate for increasing attic insulation to R-30.

Older homes rarely have insulation in the basement or crawlspace floor. This usually becomes a big problem over time as cracks develop in the flooring and air from under the house will start leaking through it. With the temperature differences between the inside of the house and underneath it, condensation and mold become common. The best solution is to apply spray foam up to R-19 on the flooring underneath. This forms an insulating vapor barrier and completely seals the house floor from the basement or crawlspace thus eliminating leakage, condensation and a place for mold to grow. Fiberglass batts can also be used but they need to stay in contact with the floor. After a few months the batts start to settle and pull away from the floor which greatly reducing their insulating effectiveness. Fiberglass batts are also not a vapor barrier so a vapor barrier needs to be installed for this process to be effective. Even though it cost more to use spray foam, we usually recommend it because the results are far better and more permanent. For our Georgia Power customers there is a $450 rebate for increasing floor insulation to R-19.

Insulating crawl space walls and installing a vapor barrier on the ground is an option for some if your crawlspace is dry and stays dry. Read more.

Georgia Power also has a rebate of $550 to add insulation to the outside walls of a home. This only applies when all of the exterior walls of the house are improved. So most home won't qualify for this unless the house is undergoing major renovation work.

Minimum Recommended Insulation R-Values for Georgia:

R-Values for different types of materials: