2 - Weatherization: Air Sealing and Insulation

Electrify Brookline | How-To Guide #2

Would you love your home to feel comfortably warm in the cold winter months and comfortably cool in the heat of the summer? The good news is that renters, condo-owners, homeowners and landlords can all take steps to make sure their home is not losing heat or cooling unnecessarily by sealing cracks and adding insulation. The best news is that the Mass Save program can help with this work at little or no cost to you.

What Is Weatherization?

Weatherizing a home consists of two steps: insulation and air sealing. Building experts usually advise you to do as much weatherization as is feasible before doing other energy-saving work.

Insulation:  Adding insulation to a house is like wearing a sweater or adding an extra blanket on the bed. Insulating the exterior walls and roof will reduce overall heat loss, which means less demand for heating, and lower heating costs. Good insulation also makes a home more comfortable with fewer locations that feel cold or drafty. An added bonus: insulation will often make your house quieter!  

Air sealing:  You can think of air sealing like wearing a windbreaker over your sweater. Most homes are not airtight—they’re full of small gaps and cracks that let air move into and out of the home. This air leakage leads to a lot of wasted energy and wasted money. Air sealing plugs cracks around doors, windows, plumbing pipes and electrical conduits that allow air to leak out through gaps. In older homes, it can also involve sealing the spaces where the basement foundation walls meet the first floor framing. 

How Can This Help the Climate?

Experts will tell you that the cleanest energy is the energy you don’t use. Weatherizing your home is one of the best ways for you to save energy, reduce your climate-damaging emissions, lower your heating and cooling bills and make your home more comfortable.  A win-win-win.

What’s Involved?

Mass Save is the Commonwealth’s utility-sponsored program to provide energy efficiency resources to electric and gas customers, funded by very small fees on monthly utility bills across the state. Mass Save provides no-cost home energy assessments to all utility customers living in 1- to 4-unit homes, whether renters, condo-owners, home-owners or landlords. Mass Save also has commercial programs designed for larger buildings. The Mass Save home energy specialist will review your current appliances, equipment and energy use, outline useful and cost-effective energy improvements, help you develop a plan to make your home more efficient, and inform you about rebates and incentives you may qualify for.

Here’s some of what you’ll receive from your assessment:

  • A customized energy report tailored specifically to your home and emailed to you.
  • No-cost energy-saving products recommended during your assessment delivered to your door which may include:
    • ENERGY STAR® certified LED bulbs
    • Advanced power strips
    • Low-flow showerheads and faucet aerators
    • Efficient thermostats
  • Up to 75% or more off approved insulation improvements
  • No-cost targeted air sealing

Mass Save can also provide a list of eligible contractors so that you can get competitive pricing for any of the work you plan to do. The incentives for weatherization make the cost of this work heavily discounted and sometimes totally free.

If you are interested in making energy efficiency and comfort improvements to your home, the Mass Save Assessment is definitely the place to start – and is often a requirement for some of the available rebates, incentives and no-interest loans. And the good news - the energy assessment is free! To schedule a no-cost Home Energy Assessment, start by calling 866-527-SAVE, or go to the Mass Save website to learn more.

Other Considerations

Older homes may still have old wiring, called “knob and tube wiring.”  A licensed electrician must check throughout your home and then certify that any remaining knob and tube wiring is completely inactive before air sealing or insulation can be carried out. Mass Save often will cover the cost of this assessment as part of a weatherization improvement project.

Available Rebates and Tax Credits

You can access generous Mass Save rebates and incentives to make recommended long-term energy-saving upgrades to your home, including 0% financing and 75% or more off approved insulation.  With the Mass Save incentives, recommended air sealing is usually at no cost; insulation can be free or in the range of a few hundred to a few thousand dollars, depending on the size of your home.

In addition, discounts and tax credits are becoming available in 2023 as a result of the federal Inflation Reduction Act (IRA) , with plans to offer an upfront discount of up to $1,600 for income-qualified residents, and a 30% tax credit for weatherization projects, capped per year at the following amounts:

  • Insulation and air sealing: $1,200
  • Doors: $250 per door, $500 total
  • Windows: $600
  • Energy audits: $150
  • The credit resets each tax year, effectively becoming available again for additional projects.

A no-cost Mass Save assessment is often required to access MassSave rebates and incentives; the assessment is helpful but not required to access Federal rebates and incentives.

A good resource for information on the new IRA rebates is Rewiring America, where they provide IRA fact sheets and a savings calculator.  Another good resource is the Massachusetts Clean Energy Center, which includes a table on available incentives from both our state and the federal government.

IMPORTANT:  Verify with your installers that they have the proper licenses and insurance, and confirm that they have or will obtain all required permits and inspections from the Town of Brookline.


About Electrify Brookline

Electrify Brookline is a collaboration between the Town of Brookline’s Zero Emissions Advisory Board (ZEAB), Mothers Out Front Brookline and Climate Action Brookline.  Our goal is to provide clear information to guide the community on the path toward electrification — improving the energy efficiency, health and comfort of their living spaces while reducing climate-damaging emissions to preserve a livable future for all.

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