My plan to cut my carbon emissions to zero
My partner and I have lived in our home for about 8 years. We’ve got 3 kids, one bathroom and 3 bedrooms. Things have been feeling quite squishy lately with all of us working and schooling from home.
Trish and I have found that when working with homeowners, the path to cutting home emissions is best when it incorporates the way that occupants use the space and their future goals.
Rather than aim for perfection along the way, we recommend that every step a homeowner takes shouldn't create barriers but instead gets the them one step closer to cutting fossil fuel emissions. For my home, the need for more space and an unfinished basement is our carbon cutting opportunity.
The other thing we’ve learned is that homeowners need to be talking and sharing their plans and experiences more. Homeowners who have cut their home emissions love sharing and homeowners who want to make changes but don’t know how get inspired when they hear these stories. I’m a part of an east end climate collective called TEECC. A few weeks ago I invited two homeowners (who we’ve blogged about here and here) to share their experiences during our weekly meeting. It was amazing to see the inspiration - it’s infectious! So I hope that by documenting and sharing my own experience I can inspire you to get going on the path to zero emissions.
The Basement
As mentioned above our basement is unfinished. The ceilings are about 5.5’ and with the ductwork it’s closer to 5’. So we know we need to dig down to create more height. I’ll add 1.5” - 2” of insulation before the concrete slab is repoured. These days hydronic in-floor heating is all the rage for basements but I think that a few inches of insulation will make it nice and cozy down there (it’s like putting slippers on the floor!).
The walls are double brick and covered with this ugly white parging that’s coming off. I’m still on the fence as to how we’ll insulate the walls. I’ve received a few quotes and most contractors love to use spray foam when insulating. I get it. Spray foam is way easier to install as you don’t need to worry about a vapour barrier (it acts as one) and you don’t even need to frame. But the embodied carbon of spray foam is pretty high (compared with other products). I’ll likely keep trying to find a contractor who will install 2” of rigid insulation made with Rockwool (the product is called ComfortBoard) and then frame with 2x4s and fill those with Rockwool as well. I won’t go into a detailed comparison as this blog I wrote does a pretty good job comparing the options.
my son enjoys picking off the parging which reveals this lovely greenish paint on the brick!
For the energy nerds out there, the basement walls will have an effective R value of R19 which is a bit better than framing with 2x6s and filling with Rockwool (which is R18) and much better than the standard approach of framing with 2x4s and filling with fibreglass (R10).
My energy consumption will go down by 12% which translates to approximately $200 saved/year. More importantly, our basement will have a bathroom, more livable space, it won’t smell musty and it’ll be super comfortable!
Heat Pumps
By improving our basement we’re reducing the size of furnace we need to heat our home. It may not come as much of a surprise that we’re going to chuck that furnace (or try to find an interested recipient for a 10 year old furnace) and install a heat pump. By insulating our basement we reduce the size needed by 40% which means we can spend $2,000 less on a smaller heat pump.
More importantly, switching out our fossil-fuel burning furnace for a delightfully clean heat pump cuts most of our home emissions (heating accounts for 75% of my home’s emissions).
We’re also going to remove our gas hot water tank which is also 10 years old and replace it with a heat pump hot water tank. Although the tank has not yet reached it’s end of life, it’s a good time to replace it as we’ll have plumbers in anyway for the basement bathroom and this’ll save us $ in the long-term (and of course gets us off fossil fuels sooner!).
Switching out our fossil-fuel burning hot water tank for a delightfully clean heat pump tank cuts the largest remaining chunk of our emissions (hot water accounts for 20%).
We’ll then just be left with a gas stove which I am eager to replace with an induction stove when we renovate the kitchen at some point (and we’ll then be able to cut our gas service altogether!)
Historical representation of heating solutions in my 100 year-old home. The chimney is currently only used to exhaust the gas from the hot water tank. The soot door can be seen in the bottom right.
The Roof
Our roof is also overdue to be replaced so that’s going to happen after the basement so that we can remove the redundant chimney. With a new flat roof that faces south we are prime candidates for renewable energy through solar panels. The solar panels will produce about 60% of the energy I calculate we’ll consume.
If by the summer the $40,000 interest-free loan program is in place, I hope to qualify for it to help cover the costs of a solar array (it’ll cost approximately $22,000 to install a 7.7 kW array). The solar panels will save us $1,500 - $2,000/year in electricity bills so we’ll use that to pay off the loan in 13 years.
Electrical Panel
Want to check if you have 100A or 200A service? Look at the switch at the top. It’s 100A here.
To install the heat pump for heating and heat pump hot water tank and to make sure we’ve got the capacity to charge an EV when our current vehicle goes, we’ll need to upgrade to a 200 amp panel. I’ve checked and we don’t quite have the capacity on our current 100A panel to accomodate everything we need. I’ve found that homeowners who are switching our fossil fuel appliances for cleantech don’t often consider their electrical panel. But it’s a great first step for any homeowner (and while you’re getting your panel replaced grab a can of spray foam and make sure to seal up any spots that seem drafty - I often find a lot of air leaks around and behind electrical panels).
What have we already done?
When we first moved in we replaced all the 100 year old single pane windows with well-sealed double-pane windows. We replaced the rotting cedar siding with vinyl siding and added 1” of rigid insulation underneath. The siding is my one big regret. I wish we’d have added at least 2” of insulation and considered a more environmentally friendly siding such as cedar or metal. For more on why vinyl is not great for the planet check out this blog. Now I know better but this experience also helps remind me that we can’t all build the perfect new home from scratch and need to find creative ways to improve what we already have.
You may also recall that a few months ago we had the attic insulated and I’ve done extensive air sealing.
What else could we do?
Alas, there’s often more that can be done on our beautiful century-old homes. Our main floor walls are all double brick without any insulation on the inside. So during the winter they are quite cold to the touch. In the future, it would be great to add insulation to them (from the inside or outside). And rather than waiting for all the walls to be perfectly insulated, I’m seizing the opportunity to switch out the two big fossil fuel emitters (furnace and hot water tank) for heat pumps and get a solar array on that nice new roof.
I love old homes! Double-brick walls were common in Toronto in the early 1900s and are easy to detect from the outside. Look for bricks that are about half as skinny. These bricks, called tie-bricks, are used to connect the first and second layer of bricks.