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Barriers to installing insulation

Before you insulate, your home must meet certain safety requirements. But don’t worry! Your Mass Save Energy Specialist can help.

A Mass Save Energy Specialist can identify any potential barriers to insulation during the Home Energy Assessment. They'll let you know if there are any available incentives to help fix the issue before insulating your home. Call 617-635-SAVE (7283) to schedule your assessment today!

To take advantage of the generous Mass Save® incentives on insulation, we need to ensure that your home meets certain criteria. Some homes may need a little extra work before they can be insulated due to certain insulation barriers. We call these “weatherization barriers.” Through Mass Save and the DOER Expanded Heat Loan program, great incentives are available to help pay for any weatherization barriers preventing insulation! Remember, the first step is to schedule a no-cost energy assessment from a Mass Save Energy Specialist!

'Knob and tube' electrical wiring

What is it?

Knob and Tube wiring is a common method for wiring electricity in homes up until the 1940s. Electrical wires are covered by “tube” casings that are held in place by ceramic “knobs.” This system only has two wires, a black “hot” wire and a white “neutral” wire, but lacks the “ground” wire that modern systems have. Over time the protective casings around the knob and tube break down, which may pose a fire hazard.

In some cases, homes will have inactive knob and tube systems hidden in their walls or basement. This is usually the situation if a home was renovated or re-wired to a modern electrical system. This means that the knob and tube structure was not removed when the home was re-wired. You will still be able to proceed with insulation as long as the knob and tube system is inactive. 

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How can we help?
  1. Mass Save offers a $250 rebate to hire an electrician to determine if the wiring is live. If it's inactive, you can proceed with insulation.
  2. If the wiring is active, the Expanded HEAT Loan offers a $3,000 grant for re-wiring or up to 25% of the total job cost. An electrician can give you a quote for the project. Total project costs vary depending on the home.


What is it?

Asbestos is now understood as a dangerous carcinogen. That means it can cause cancer. Before this discovery, asbestos was used to insulate attics, heating systems, and pipes. It can be very dangerous to human health.

If asbestos is present in certain areas of the home, it must be removed before any insulation work is done. If there is asbestos pipe wrap in the basement, you can still insulate your attic without any issues.

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How can we help?

If asbestos is found, you're able to receive a $3,000 grant for its removal through the Expanded HEAT Loan.

Carbon monoxide

What is it?

Carbon monoxide (CO) is a colorless, odorless gas that can be harmful when inhaled in large amounts. CO is released when something is burned.

The greatest sources of carbon monoxide to outdoor air are:

  • cars and trucks, and
  • other vehicles or machinery that burn fossil fuels.
How can we help?

Mass Save offers a $250 rebate to hire a HVAC contractor to tune up your heating system. There are also generous Mass Save rebates up to $3,500 to upgrade to more efficient heating equipment.

Get help

Home Energy Assessment

Schedule your no-cost Home Energy Assessment today to see if you’re eligible for insulation improvements! Call 617-635-SAVE (7283).

For other issues such as lead paint removal, additional funding and rebates can be provided by the Boston Home Center. Find out if you qualify by calling the Boston Home Center at 617-635-3880.

Income-eligible residents

For income-eligible residents, the Action for Boston Community Development (ABCD) program offers:

  • fuel assistance
  • no-cost weatherization and insulation, and
  • no-cost heating system replacements for certain qualified participants.

To learn more, call ABCD at 617-348-6000 or visit

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