Planning for Net Zero: One Step At A Time

Location: Newton, MA
Type of home: Condo in Two- Family Building
When first built: 1915
When last renovated: 2012


Seven years ago, I bought the upper condo unit (second and third floor) in a two-family home that had been updated and converted to two condos.  It was built in 1915. My unit is 1,900 square feet and has a recently replaced (but not very efficient) gas boiler, a gas hot water heater, no central air conditioning, and a new gas stove.


Added Insulation Inside Knee Wall

Energy Assessment for our Condo

One of the first things I did when I moved in was to ask for a MassSave® no-cost energy assessment.  The assessor gave me free LED lights and identified there was almost no insulation in the walls and single paned, very leaky windows in the basement.  I didn’t know my downstairs neighbor well enough to get approval for wall insulation (it would have required us to participate at the same time) so I had a MassSave® insulate the knee walls on my third floor.

What in the world is a knee wallI didn’t know myself!  When an attic space has been converted into living space under a pitched roof, you often get short “knee walls” on the side. As you can see in the photo, MassSave® added insulation foam board so air and heat would no longer gush out of the third floor and be wasted. MassSave® paid for 75% of the $2,300 cost for the knee wall insulation.

Knee Wall

At the same time, I replaced four single-paned windows in our basement that were in terrible condition. I took out a 0% 7 year MassSave® HEAT Loan to finance the window replacements.





Energy Assessment for the Building

After 3 years of getting to know my condo neighbor downstairs, I was able to convince her to have MassSave® come back again to insulate the walls. HomeWorks (one of the MassSave® Home Performance contractors) was able to blow in cellulose dense pack insulation made of recycled newspaper from the outside of the house.  MassSave® paid for 90% of the insulation cost.  For $11,000 of wall insulation work, my condo-mate and I each paid $500 only each.  What a deal!  Both of our units have been so much more comfortable in the winters since!



Weather Stripping for Door to Unheated Porch

New Air-Tight Recessed Light

Got Rid of Other Drafts

Even though MassSave® didn’t identify areas where I had a lot of air leakage, I’ve been on a mission to stop wasteful and uncomfortable drafts. The worst offenders were 12 recessed lights on my 3rd floor and edge of kitchen that go directly to the outside cold air.

Recessed lights are notorious for leaking a ton of air.This means higher heating and cooling bills and  persistent drafts. I had my electrician switch out the lights for air-tight versions that have a glass face.  There are also inexpensive retrofit kits available.

I don’t use my fireplace, so I added a removable chimney blocker I bought online and I also bought peel and stick weatherstripping for a door that leads to an unheated porch that was leaking a lot of air.



Results = Savings + Comfort

It’s hard to estimate exactly how much energy we are saving.   My best guess is there is slightly more than a 30% reduction in heating and cooling energy. The biggest difference though is clearly in comfort!  It is so much more comfortable in the winter.   And feel I good helping our climate by cutting down on wasted energy in our home.

When trying to improve the efficiency of your home, my advice is to take advantage of MassSave®.  It’s a great deal and they are much better at recommending insulation than in the past.  But that is not enough to make your home efficient!  Think through what air leakage problems you might have and/or bring in an energy professional to take your home to a higher level.



Chose 100% Renewable Electricity

Buying Renewable Electricity with MassEnergize

The City of Newton has competitively procured renewable electricity, so for a tiny premium (for me it’s been less than $1 per month more) I choose to buy 100% local renewable electricity.

If you live in a town that doesn’t have municipal aggregation for renewable electricity, there are still many options for buying 100% renewable electricity for a small premium.  Contact your local environmental group or a group like MassEnergize for suggestions for companies to buy from (you do want to watch out for scam artists). A community solar subscription is another possibility.



My Electric Vehicle

Replaced Car with An Electric Vehicle

I had one car, a twelve year old Prius, for our family.  For awhile I’ve been wanting to purchase an electric vehicle (EV).  When my oldest son needed a car for a job in Vermont, it was the perfect excuse for me to get an electric vehicle.

Green Energy Consumer’s Alliance was incredibly helpful in answering my questions and narrowing down which models would be best for me.  They also pre-negotiate bulk prices at many dealerships in Massachusetts.  Teslas were too pricey for me.  I seriously considered buying a Chevy Bolt (several of my friends love theirs) There were a number of 3 year old Bolts coming off leases.  But in the end, I sprang for a 2020 Nissan Leaf with a 230 mile range.

I am so pleased with my purchase!  The $7,500 federal tax credit and $2,500 state incentive certainly didn’t hurt, but the big win for me is avoiding the hassle of maintenance and oil changes.   With no internal combustion engine, there is very little to maintain, and I also get to avoid having to go to gas stations.  I am just using the trickle 110 volt outlet in my garage for now since I drive so little.  Because I buy 100% renewable electricity, my EV is a great choice for the climate.



Net Zero Goals

Planning to Get To Net Zero Over Time

On my list for the future:

  • Replace my gas hot water heater with a heat pump water heater. (the side benefit is that it will dehumidify our basement)
  • Install mini-split air source heat pumps for heating and cooling
  • Replace basement door which fits poorly and leaks air
  • Try again to get condo-mate to approve solar on our roof.



Putting Everything In Perspective

Do what you can.  You should absolutely not have guilt if your home is not perfect and if every action you take isn’t the best possible environmental decision. Not everyone owns a home or has the resources to get to net zero.

If you have limited funds or limited time, what is important is that you focus on the biggest personal actions you can take on climate:

  • Reduce how much beef you eat, and
  • Get on a plane only when you need to

And instead of putting in hours of research into buying most sustainable purse, fretting about using disposable or cloth diapers, the lifecycle of paper or plastic etc., spend that time and effort joining with others to take collective action related to climate.

Find a local climate group, bring your friends, and take collective action to make policy change.  A well-timed email to your city councilor, state representative, Mayor, or an editorial in your local newspaper or Nextdoor feed can make many times more impact than your personal action.

We need both the right policy framework and collective personal action to get to the state’s climate goals. What is important is that you do the best you can to contribute in the best way you can.



We’re In This Together

Pledge to reduce your home’s carbon footprint by replacing old systems and appliances with clean energy technologies over time.