solar hot water

Solar Hot Water provides savings, cool basement in summer

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.

Comfortable ducted air-source heat pump replaces old, inefficient oil boiler and baseboards

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.

Renovations, rodents, and renewables

Location: Concord, MA
Type of home: Single Family
When first built: 1974
When last renovated: 2019

We bought our 46-year old, wooden clapboard house about five years ago and it seems like we’ve been immersed in home projects since then. The house has 2,600 square feet of living space on two floors, an unfinished basement, and a two-car garage with an unfinished space on the second floor above it. Not all of our projects have been energy-related but we’ve tried to improve efficiency as we’ve tackled deferred maintenance.

We moved in near the end of the cold and snowy winter of 2015, and immediately we learned three things: 1) the house was chilly and drafty even when the thermostat was set to 70⁰ F, 2) the roof on one side of the house was prone to ice dams, which caused leaks near the ceilings in two of the bedrooms and 3) animals were living in the attic. Our clean energy home journey so far has been intertwined with correcting these three situations.


Electric service upgrade

We upgraded the electrical service to our home from 100 amps to 200 amps at a cost of $2,500 during the first month we lived in our home. Modern electric service enables us to do things like run a hairdryer and a microwave on the same circuit at the same time, which wasn’t possible prior to the upgrade. It also enabled us to install a solar PV system, which I’ll talk about later.


Attic insulation and weatherization

In our first Spring, we got an energy audit from Mass Save®. From that assessment, we got some free LED lightbulbs, learned that the attic insulation was inadequate and confirmed that numerous squirrels had taken up residence there. It turns out that a poorly insulated attic also transmits heat from the house to the roof. In the winter, this creates ice dams on a snowy roof and contributes to leaking. In the spring, we cleaned out the attic, evicted the squirrels, and then had the attic air-sealed and re-insulated by a contractor recommended by MassSave. The attic air-sealing makes the space more airtight and blocks animals from getting in, and the insulation has made the upstairs floor of our house feel much warmer in the winter.

My Clean Energy Pledge included adding large amounts of insulation to our attic.

This room used to have a wood paneled interior and now has sheetrock walls. After removing the paneling, we fully insulated the two exterior-facing walls.

The space where I’m standing is leads to our living space so this exterior door is air sealed and insulated.














I’ll take a serving of energy efficiency with my windows, garage, and lighting, please!

We did a more comprehensive round of home improvements at the end of 2018 through early 2019. Though most of the house’s windows are double-pane with fiberglass frames, we had some original wood-frame windows left on the house that were deteriorating. We replaced them with double-pane windows, which are more insulating in winter than the windows that were there before. They have a U-Factor of .30, on a scale of .25 – 1.20, with a lower number being best. I do see that they are Energy Star certified for mid-Atlantic states but not MA, and I would definitely prioritize windows that are efficient for the MA climate in the future.

In addition, the part of the garage where the wood meets the foundation, called the sill, was rotting & needed to be replaced. In the course of that project, the garage walls were insulated with blown-in cellulose insulation. Why insulate the garage walls if we don’t live in that space? We think we might eventually finish off the space above the garage and it’ll be more efficient to heat and cool that room if it’s not exposed to extreme heat and cold underneath it. Its also great for the garage to be warmer than the outdoors in winter, since it shares one wall with our current living space.

We had almost no overhead lights in the house and craved a brighter environment. We had recessed LED lights installed in multiple rooms and learned that instead of the tall cylinders that used to be required to achieve the same look, now there are much thinner light assemblies that don’t disrupt the insulation above and around them. Whereas “can” lights used to require an insulating box around them or need air sealing, the new version is hassle-free and compatible with our insulation improvements.


Weatherization results

The winter of 2019-2020 was the first one with the house out of renovation mode and with weatherization and energy efficiency measures in place. It was also a warmer winter according to the number of “heating degree days” as compared to past winters. Our gas bill from that winter was about $300 lower than in previous years. You can see in the graph above that our natural gas use correlates closely to the number of heating degree days within each bill cycle. The gas usage from June – September is associated with cooking and hot water only.


The winter of 2019-2020 was the first one where the house was not under construction and we could get the benefit of our energy efficiency upgrades.


I think it’ll take a couple more winters to accurately quantify the savings from our energy efficiency and weatherization improvements. I can attest that the house felt cozier last year and seemed to be a more even temperature in all the rooms. Eventually we’ll replace our gas furnace with heat pumps, but that’s a topic for a future blog!


Even on a wooded lot, solar works for us

We didn’t really think our house got enough sun to be a candidate for solar panels. But using the Project Sunroof tool on the EnergySage website, we were able to see that our roof had good sun exposure. Here’s the view of our southwest-facing roof, now with the solar panels on it.


Aerial view of our home’s roof after solar panels were installed.


We learned that our investment in solar panels would pay for itself over time, meaning that the electric bill savings and SREC-II payments we’d get would equal what it cost to install the system and then we’d be cashflow positive after that. The idea of generating clean electricity and making money using our roof space appealed to us.

In late 2017, we had a 7.7 KW system installed. Given that the roof had previously been leaking during the winter, we decided to also replace the roof on the part of the house where the solar panels were being installed. That increased the cost of the project but gave us the peace of mind that the roof beneath the panels will last at least as long as the panels, and wet weather won’t damage our house. We chose to purchase our solar energy system, rather than enter a third-party ownership arrangement, because we had the financial flexibility to do that. Here’s an interesting graph that shows our electric bills the year before we had solar installed and the two years after:


Starting in early 2018 when we had a solar electric system installed, our electric bills are lower overall and nearly vanish from May – October.


Here’s how the investment in solar has worked out financially, so far. We love seeing really low (and sometimes negative, meaning we’re getting credit towards future bills!) amounts on our electric bills. We’ve only gone through one full year with the system and its associated payments and credits. Right now it looks like the cost of the system after incentives and tax credits will have been paid back by our electric bill savings and SREC-II payments after 7.5 years.


This is my tracker of our solar incentive payments and energy savings as compared the year before our solar installation.


What we’ve learned

  • Standard free energy audits won’t cover the entirety of the energy efficiency measures you need to take in your house. Feel empowered to start with those free recommendations and take it further, especially in older homes.
  • Contractors or architects won’t always have energy efficiency front-of-mind when discussing home improvement plans. Be comfortable advocating for solutions that serve a shared purpose of reducing your home operating costs, lowering emissions, and improving the way your home looks.
  • Export your utility bill history from the respective online billing portals. Even if you haven’t made energy-related improvements yet, you need a baseline to compare your improvements to. I found it hard to get more than three years of billing history, even though we were the ones paying those bills in 2015 and 2016.
  • Keep records that help you articulate the value of your energy-related home improvements. When we eventually sell our home, its monthly operating cost will likely be lower than other competing homes of the same age that are for sale. Until then, we are happy to enjoy these improvements that make us more comfortable and help reduce the carbon footprint of our home!



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.

Electric Vehicles

Transitioning your car to an electric vehicle (EV) will dramatically reduce your household’s greenhouse gas emissions, while saving you money on the fuel costs and maintenance that are customary with a gas-powered automobile.

Additional Resources for Electric Vehicles

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.

Clean Electricity

You have a number of options to supply your home with clean electricity. Installing solar electricity (PV) is a great way to transition a portion of your home’s electricity to clean sources. If you are not ready or able to invest in a solar PV system, buying clean electricity or participating in community solar are two other ways to begin the transition to clean energy.

Additional Resources for Clean Electricity

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.

Getting a century-old triple decker ready for the next 100 years

Location: Jamaica Plain, Boston, MA
Type of home: Triple-decker
When first built: 1929
When last renovated: 1988

For the last six years, I’ve lived in the first-floor condo of a triple decker in Boston’s Jamaica Plain neighborhood. The building was built in 1929 and divided up into three condos in 1988. I found this personal history from Magnuson who grew up on the third floor of my building in the 1950s and 60s, and he tells the story of the first time this building went through a major HVAC upgrade.

Roy Magnuson said, “One big issue was the heat. Not enough of it in winter, and too much of it in summer.” It turns out that the house was heated by a coal-fired boiler that was a big ordeal to start every winter and had to be loaded several times a day until the 1960s, when it was converted to oil. The hot water was heated with a very dangerous-sounding unvented appliance in the kitchen called “the stack.” So you can imagine that Roy was excited to have the heat and hot water switched over to an oil boiler. As for cooling improvements, Magnuson describes how his mother saved money from her job to buy “two small air conditioners, one for each bedroom” in the mid-1960s, making their family one of the first in the neighborhood to have air conditioning.


Oil Heat’s Not a Treat

The oil heating that our unit still has today (not the same boiler, ours was installed in 2011) is undoubtedly an improvement over the manually loaded coal boiler and “the stack” that Magnuson describes, but our radiators still clang and bang like the author remembers, and we’ve never been able to get our hot water to stay hot for an entire shower, especially in the winter. For cooling, we still use window air-conditioners. We had two (one for each bedroom) just like Magnuson until we had to stay home for parental leave in the summer and got a third one for the living room. If we’re going to be working from home more often, cooling will become more important to us.


An Air-source Heat Pump

A Solution for Both Heating and Cooling

We’re planning to switch our home over to air-source heat pumps, which provide both heating and cooling, at some point in the next year or two.

Because we have oil heat, we are eligible for generous incentives through Mass Save, although I expect it will still be a relatively expensive investment in our home. In MassCEC’s whole-home air-source heat pump pilot, the average retrofit project has cost just under $22,000 before incentives for homes averaging 1,600 square feet.

With a condo around 1,000 square feet, I’m hoping that my costs will be lower. I am definitely planning to use Mass Save’s 0% interest 7-year HEAT Loan to spread out that cost.


My electrical panel with 100 amp service.

But First, an Electrical Service Upgrade

To accommodate air-source heat pumps, our home requires an electrical service upgrade. The condo currently has 100 Amp service, and I would most likely need to upgrade it to 200 Amp service if I want to install heat pumps (and a heat pump water heater and electric car charger) in order to have enough electric current to serve all those electrical appliances. Typically, MassCEC estimates that this upgrade would cost $2,000 to $3,500. However, for some households it can cost more, especially if the electric service to your home is buried underground. My electric service is overhead, but I had an electrician come look at my home, and they said that in order to meet code, if they upgraded the service they would also need to move the electric meters from the basement to the outside of the home and they would need to add a common meter for our triple decker (we currently just have three, one for each unit). All these changes meant that the quote to upgrade my electric service was $6,800. Honestly, I’m a bit stuck on this issue. For now, I am just planning to have an electrician install a double pole 30 Amp circuit breaker to add a heat pump water heater (discussed below) and monitor what our actual amp draw is before we start thinking seriously about our air-source heat pump project. For more information on electric service upgrades, including resources to determine your home’s existing electric service (amperage) see the Introduction to the Clean Energy Home Guide.


Energy Assessment for Our Condo

Before we put in a new heating system, I want to make sure that we’ve made our home reasonably energy efficient. We have had a no-cost Mass Save home energy assessment, which found that there is already blown-in cellulose insulation in our walls. Although it is a little loose and has some gaps, because there was already some insulation in the walls, Mass Save couldn’t recommend new insulation.


Energy Assessment for the Building

As I’ve thought more about the building, it would be ideal to get my upstairs neighbors onboard and request another assessment (you can have an assessment done every two years) but do one for the whole building this time so that we can think holistically about the roof and basement. I also want to ask about opportunities for air sealing and see if we can weatherize our front and back doors, which have visible gaps between the door and doorframe. Windows are not generally a cost-effective energy efficiency upgrade, but they can be nice for comfort and add value to a home. We have a broken window in our dining room (if you try to open it, it falls out of the window frame), so I would like to get the dining room windows replaced and maybe also upgrade the windows in our bedroom for comfort.


Hotter Hot Water Needed

We would like a new hot water solution sooner rather than later because we currently get hot water from a tankless coil in the boiler and it often doesn’t stay as hot as we’d like. This issue is seeming more urgent as our toddler grows out of his little tub and we want to give him baths in the larger tub. Solar hot water can be a great (and affordable) option for some homeowners. In my case, because I share a roof with my neighbors, I’m planning to get a heat pump hot water heater instead.


Heat Pump Hot Water Heater

A heat pump water heater would go into our unfinished basement. In the summer, the cooling and dehumidification that it provides will be great for the basement. We will have to see what works in the winter. I have talked to one installer who has put heat pump water heaters into similar basements and he recommended that we put it in heat pump mode in the warm months, hybrid (heat pump and electric resistance mode combined) in the shoulder seasons, and switch it to electric resistance in the coldest months of the year. We’re hoping to make this upgrade soon, while being careful about having people into our home during the pandemic.


My toddler “cooking” on our induction stovetop. I appreciate that it is safer than natural gas both in terms of burn risk and indoor air quality and health impacts.

We’re Cooking (Without Gas) Now!

We replaced our stove/oven in 2018 before the birth of our son. We had an old gas stove, but it was at the end of its life (none of the pilot lights worked anymore, so we were lighting the stove with a lighter). We decided to get an induction stove, and we have been really happy with the new stove for the last two years. We had to swap out a few cooking pans, but the stovetop heats up quickly and has good temperature control. With a glass top, it’s easy to clean. As a parent to a toddler, I appreciate that the dials are out of the way and even if my toddler did manage to turn them there would be no gas leak or open flame. In fact, the stovetop doesn’t even get hot unless there is a pan on it. This has made it a lot more stress free to have my son play at cooking on our stove. But as a parent, I especially appreciate the health benefits and improved indoor air quality of not cooking with natural gas.


Car-free Now, EV Eventually

As Roy Magnuson remembers from his childhood, “One reason why JP was a great place to live was the public transportation.” That’s still true today (although it sounds like there actually were better public transit options for Roy), and we’ve been able to get by without a car so far. However, with a toddler, we’re certainly thinking about getting a car. If we do, we’ll get an electric car. There are more and more options on the market each year, and we would probably go through Green Energy Consumers Alliance’s Drive Green program to get a good deal(and take the stress out of negotiating a car price).

For charging, we have a parking spot in our driveway where we could keep the car. At a minimum, we could charge the car through a regular outdoor outlet.

EV charger photo credit to Marco Verch via CreativeCommons

We might like to install a Level 2 charger which would let us charge the car faster, but that would require the electric service upgrade that we are currently stuck on.


Clothes Dryer

We already have an electric clothes dryer that works fine. We’ll keep using it until we start to have issues, and at that point hopefully there will be even more heat pump dryer options on the market. It would be nice to have a dryer that didn’t require venting and be able to get rid of that opening to the outside. Not to mention having a much more efficient dryer!


Renewable Electricity Plan

We buy electric offsets through Green Energy Consumers Alliance’s Green Powered Program. I like that they support renewable energy projects in New England. Our building’s flat roof is probably a good site for solar PV, but with the joint ownership and the three separate meters, I haven’t pursued it.

Resources that have recently been, are in, or are contracted with Green Energy Consumers Alliance.


Our floorplan

Triple-Decker Design Challenge

And for all of the rest of you out there who live in triple deckers, I’m keeping an eye on MassCEC’s Triple Decker Design Challenge. MassCEC asked for proposals from design/build firms, architects, and others to identify replicable triple-decker energy retrofit approaches to make these homes into high-performing, low-carbon buildings. MassCEC is offering approximately 9 prizes starting at $15,000 for the best solutions. See the ideas we received!

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.

Clean Energy Home Plan

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.

Introduction to the Clean Energy Home Guide

Introduction to the Clean Energy Home

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.

Automated Wood Heat

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.

Technologies For Your Clean Energy Home

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.