Attic Insulation: Great for Savings and Comfort

Feb 19, 2010 | Energy Efficiency

Snapshot | Savings | Do I have enough? | Environmental | Rebates | Take action!

Snapshot

When you want to save money and be more comfortable, attic insulation should be a top priority.

Add more insulation to your attic if you have 6 inches or less. In the San Francisco Bay area, your insulation should be about 10 inches deep, for an R-value (R-value measures insulating value) of R-30. Twelve to fourteen inches of insulation (R-38) is even better.

If you have comfort concerns -- if you're too hot or too cold -- attic insulation is especially critical. Heat rises from warm spaces to cold. Blanketing your attic with insulation can cap this heat flow, keeping it in your home. In the summer, insulation prevents attic heat from seeping into your living space.

Before boosting or replacing insulation, seal all air leaks between the living space and the attic, such as around chimneys, lights, vents, and ducts. Your insulation won't deliver great results without this step.

Savings

Installing insulation is cost-effective if your attic is uninsulated or minimally insulated. Some utilities even offer insulation rebates (see details below.) Typically, if you have little or no insulation, insulation will pay back in two to three years. If you have a bit more insulation, the paybacks are longer -- seven to twelve years -- but you will feel an immediate difference.

The measure of insulation's ability to resist heat is its "R-value" (the R stands for "resistance"). For the San Francisco Bay area, an R-value of R-30 to R-38 (about 10 to 12 inches of insulation) is recommended. More insulation will increase savings and comfort. Get the highest R-value you can afford.

Remember: Sealing air leaks is key to insulation performance. You could be wasting money by installing insulation and skimping on air sealing.

Are your joists showing? You have too little insulation. Also check for dislodged, compressed, and eroded insulation. Photo: WattzOn
A well-insulated attic has lots of still-fluffy insulation touching all surfaces it is insulating. Note the joists do not show. Photo: WattzOn Want to talk over your options? Have questions? Speak with a WattzOn Green Home Expert for free. Call 1-800-314-5997. Do I have enough insulation?

A simple look around your attic can help to evaluate your insulation. Here's what to look for.

Make sure you have insulation on the odd spots. Check out your knee walls (vertical walls with living space directly behind them), the attic door, and skylight shafts. We often see homes where this insulation lying on the attic floor but all the odd spots are uninsulated, leaving major gaps in coverage.
Check the insulation condition. Insulation is underperforms when it is uneven, sunken, wet, mildewed, disturbed by animals, or compressed where heavy items were placed on it. Folded batting also doesn't work well. Compression reduces the insulation's air pockets, which reduces the R-value. Check for air leaks. It is not always about the insulation. If you are feeling drafty and cold in the winter, or too hot in some rooms in the summer, check for air leaks underneath your current insulation.
Environmental Considerations

Adding attic insulation is one of the easiest ways to go green, as it reduces wasted energy and shrinks your carbon footprint.

There are several green insulation products. Cellulose is made of recycled newspapers treated with silicates and boron, so it's fire- and insect-resistant. Cotton insulation is composed of cloth left over from clothing manufacturing. And many new spray-foam products from soy and other plants are coming on the market. Although fiberglass and rock wool insulation are made with high-energy processes, but they contain some recycled content. See Eco-friendly Insulation Options to learn more.

Rebates

Attic insulation rebates for San Francisco Bay Area customers include:

Utility

Rebate Summary

Getting Started

Alameda Municipal Power

Up to $960 per home for insulation and weatherization. Free energy audit for weatherization help also available.

Details

City of Palo Alto Utilities

Up to $150 per house (upgrade to R-30 for pitched roof or R-19 for flat roof). Up to $200 per house (upgrade to R-38 for pitched roof)

Details

Pacific Gas & Electric

Up to $150 per home

Details

Silicon Valley Power

Up to $175 per home

Details

Take action!

Install more attic insulation

Want to talk over your options? Still have questions or concerns? Want to find a quality contractor?

Speak with a WattzOn Green Home Expert for free. 1-800-314-5997

We are your free, independent, qualified, green home energy experts. We don't sell windows, furnaces or insulation or anything else for that matter, and while we can recommend products, we don't get paid by manufacturers. What we do provide is informed, expert and unbiased guidance on your best and most-effective opportunities to save energy, save money and make your home more green. WattzOn can also connect you to our network of qualified and verified local green home energy auditors and green home contractors who do great work. Keywords: attic insulation, blown in insulation, blown-in insulation, blow vs batt, best attic insulation, do I need more attic insulation, how much insulation do I need?, adding more attic insulation, best type of attic insulation, best insulation contractor, cellulose, fiberglass, cellulose vs fiberglass, batt insulation, R-19, R-30, R-38