Clean energy journalism for a cooler tomorrow

Weatherization can keep you cool this summer — and warm next winter

Insulating, weatherstripping, and sealing your home could make it much more energy efficient, keeping you comfy for less money while helping out the grid.
By Alison F. Takemura

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Canary Media’s Electrified Life column shares real-world tales, tips, and insights to demystify what individuals can do to update their homes for a clean electric future. Canary thanks EnergySage for its support of the column.

Bennie Tillman Jr. lives in a two-bedroom, one-bath house that his father built in Athens, Georgia, back in 1948. By 2022, it was worn-out,” Tillman told me — drafty on cold winter nights and expensive to keep cool in the Southern summer. 

That October, contractors breathed new life into the home. They sealed cracks and gaps in the building’s shell that let outdoor air sneak inside, added a moisture barrier to the dirt-floored basement, and installed insulation in the attic and basement. The energy-saving home makeover was covered by federal funding at no cost to Tillman, 68, or his wife, Annie Mattox. 

Now, the home is much better at holding on to heat in the winter and staying cool in the summer. During the hottest and coldest times of the year, the couple saves roughly $200 a month on their energy bills, Tillman said. It’s an amount so sizable for the pair, who live on a fixed income, that he thought at first it was a mistake.” 

But the upgrades have been delivering on savings and comfort ever since. We’ve been in a heat wave all summer,” Tillman said. Yet the air conditioner only needs to kick on about a quarter as often, and last month’s electric bill was about half of what it was before the weatherization work was done. 

An uninsulated home is like a paper bag: at the mercy of the elements. But sealing and insulating your abode can make it more like a temperature-retaining beverage cooler. These measures can also help when the power goes out during extreme weather; they’ll give you a little bit of a cushion,” explained Doug Anderson, installation program manager at Energy Star, the energy-efficiency program administered by the U.S. Environmental Protection Agency. 

How big of a cushion depends on the home and local climate, but the Department of Energy estimates, for example, that a well-sealed, well-insulated home would be habitable during a heat wave and power outage in Atlanta for four days longer than an average existing home in the city would.

These findings underscore that weatherization is an important strategy not only for getting greater value out of heating and cooling systems but also for contending with increasingly prevalent extreme temperatures. Heat waves have broiled continents and broad swaths of the U.S. in recent weeks — a climatic fever that seems unlikely to break anytime soon.

As you think about switching your heating and cooling to a two-way electric heat-pump system, these updates to a home’s shell become even more crucial. Weatherizing a home first can reduce the size of a heat pump needed, saving you thousands of dollars upfront and costing less to run.

Reducing wasted energy is both good for your wallet and key to the clean energy transition. Energy efficiency provides some of the quickest and most cost-effective means to reduce carbon emissions — and helps avoid straining the grid.

Despite the benefits, most American homes are under-weatherized. According to the DOE-backed Advanced Building Construction Collaborative, 75 million housing units, equal to 60 percent of the U.S. housing stock, are in need of sealing and insulation upgrades.

Here’s what to know before you start weatherizing.

What does sealing and insulating a home entail?

Sealing and insulation upgrades can benefit homes from decades old to brand-new. It all depends on the craftsmanship of the home,” Energy Star’s Anderson said. It’s very difficult to just look at a home and determine how leaky it is.”

Homes can be rife with cracks or gaps in their exteriors, or envelopes. Air can leak where ducts and pipes perforate ceilings, hatches open to attics, and dryer vents punch through walls.

You may be able to find many of these gaps yourself, but getting a professional to conduct a home energy audit will deliver the most comprehensive results.

To seal the cracks, you or a contractor can apply toothpaste-like caulk or install weatherstripping. Caulk, which can be made of silicone, latex, polyurethane, or other compounds, is best for stationary cracks less than a quarter of an inch wide. 

Weatherstripping, on the other hand, is designed for components that move. Coming in foam, vinyl, metal, and other varieties, weatherstripping is tacked onto doors and window sashes. For both caulking and weatherstripping, different materials are better suited to certain jobs than others, so you’ll want to research what’s best for your situation if you’re doing the upgrades yourself. 

Insulation is typically more involved and often makes the biggest difference in home energy bills and comfort. Cocooning a home’s indoor spaces from outdoor temperatures, insulation comes in a dizzying array of formats — from blanket batts and rigid boards to loose fill or sprayed foam — and a wide array of materials, including cotton-candy-pink fiberglass, mineral wool, polystyrene, and cellulose. The products have different resistances to heat flow, known as R-values; the higher the R-value, the more insulating they are.

The DOE recommends certain R-values for different parts of the home depending on your climate zone. For example, it suggests at least an R-60 level of insulation for Minnesota attics, but an R-49 level of insulation for those in southern Texas.

The best combinations of form and material will depend on your needs, your budget, and where the insulation’s going to be added. For instance, batts are well suited for unfinished walls, floors, and ceilings and are pretty DIY-friendly, while spray foam is good for irregularly shaped areas and around obstructions. But spray foam is typically more expensive and needs to be professionally installed, said Amy Royden-Bloom, manager of the residential buildings program at the DOE’s Office of Energy Efficiency and Renewable Energy. 

Insulation can be expensive, but if you don’t have good insulation [already], it can have a real impact on your heating and cooling,” Royden-Bloom noted.

Energy Star warns that insulation performance is highly dependent on the quality of the installation, so whether you do it yourself or hire a professional, you’ll want to take care to get it right. 

How much does weatherization cost? What incentives are available? 

Weatherization costs can be tough to generalize, because every home is unique. But insulating and sealing a 1,000-square-foot attic can cost roughly $1,200 to $2,200 for a homeowner doing the work themselves, or $2,500 to $4,500 for contracting it out, according to Anderson. 

It can get expensive, but you know that it’s going to start paying you back in comfort and savings immediately after,” he said. And the investment can go a long way: Sealing might need to be redone every five to 10 years, but well-maintained insulation can last 100 years or longer, according to the International Association of Certified Home Inspectors. 

These updates can save homeowners 15 percent on their heating and cooling bills on average, according to the EPA, with bigger savings in places that see greater temperature swings. Even without incentives, the insulation and air-sealing measures can pay for themselves after five to 10 years, Anderson noted. 

But incentives abound. New and expanded federal carrots can slash thousands of dollars off the upfront costs of weatherizing your home.

Income-qualified households can apply to their state’s DOE-funded Weatherization Assistance Program to get these home upgrades done for free. For other consumers, a bonanza of local, utility, and federal incentives are or soon will be available to help cover weatherization costs. 

The 2022 Inflation Reduction Act created two relevant home energy rebate programs. The Home Efficiency (or HOMES) Rebates will depend on state implementation and how much energy savings a project achieves, with lower-income households being eligible for the highest level of savings — up to 80 percent of a project, capped at $8,000. No states have yet received federal funding for this program, but some states have applied for it.

The other rebate program, called the Home Electrification and Appliance Rebates, has a simpler offering: a rebate for up to $800 to cover half the cost of insulation, air sealing, and ventilation upgrades for households earning between 80 and 150 percent of area median income. For lower-income households, the rebate can be used to cover the whole project cost up to $1,600. Six states have gotten funding to start bringing their programs online.

The landmark climate law also enhanced a generous federal tax credit: the Energy Efficient Home Improvement Credit (called 25C for its section of the tax code). This credit can shrink your tax bill by up to 30 percent of the costs of materials for insulation and sealing projects (labor is excluded, unfortunately) up to $1,200. It renews every year, so homeowners could space out upgrades to claim the maximum more than once.

The tax credit can also cover up to $150 for the cost of an energy audit, the prime way to diagnose all the weatherization needs a home may have. Besides getting this home energy assessment, Anderson recommends calling your utility to ask about incentives it might offer and if it has a list of vetted installers.

Sealing and insulating your home could help you stay cooler when it’s sweltering out — all while easing the strain on the transitioning energy system. And as Anderson noted, There’s good money on the table to help you do these projects today.” 

EnergySage is the leading online comparison-shopping marketplace for rooftop solar, energy storage, heat pumps, and community solar. Supported by the U.S. Department of Energy, EnergySage is trusted by over 10 million consumers across the country to help them make smarter energy decisions through simplicity, transparency, and choice. Unlike traditional lead-generation websites, EnergySage empowers consumers to request and compare competing quotes online from a network of more than 500 pre-screened installation companies — a proven formula that has led to 20 percent lower prices on average. 

Check out EnergySage to learn more and shop for quotes! 

Alison F. Takemura is staff writer at Canary Media. She reports on home electrification, building decarbonization strategies and the clean energy workforce.