Now that we’re done with most of the decarbonization work on my house—gas line cut off, heating and cooling with minisplits, using heat pumps for water heating and the condensing dryer, cooking with induction—I have some observations and items for follow-up:
Of course you need to insulate correctly, but air sealing is vital
- When you start with a good insulation and air sealing plan (as you should!), you really do get increased comfort, especially when the house is poorly insulated (i.e. all old uninsulated houses). Ours just feels so much better now—virtually no cold spots or drafts, the double hung windows being the exception. I’ll replace them when they’re close to dead, probably 5-10 years.
- A good insulation and air sealing plan for older houses is likely not too simple. Yes, it’s fairly simple to retrofit walls with cellulose (drill and blow), easy to pour cellulose in an attic; but neither of those are simple to air seal, which is arguably just as important as the insulation. And old slabs and foundations are likewise not so simple to insulate—water management (in the form of bulk water and condensation) can be challenging, and water-resistant insulation materials more expensive.
- We haven’t seen the usual Fall/Winter mice since buttoning up the thermal envelope…airtight is rodent-tight!
- We need to keep looking for straightforward ways to answer the question, “how much and what type of insulation and air sealing is right for this house?”
Energy Grid and Infrastructure Needs
- What level of efficiency should we meet for buildings, if we want to have a zero carbon grid? If we just switched from gas to heat pumps now, I think we’d need more power plants. Not good—there is so much waste we can eliminate, but how much do we absolutely need to?
- Many (most?) houses will require electrical service and panel upgrades. If decarbonization becomes required by code, for instance, there should be a grant or other incentive program, certainly for lower income households.
Physical, Financial, and Mental Benefits
- Since the goal is to get the house airtight, ventilation becomes necessary—and boy is it nice! We have the CERV, and it’s been so great to have a better-smelling house, and one that we can ventilate with the push of a button. The recirculation function of the CERV redistributes air in the house, and whether in vent or recirc mode, it filters the air, so the air is cleaner inside.
- Cooking all-electric with induction means more beeps. Beep stove on, beep burner on, beeps if you lift the pan off the burner, and the electric tea kettle beeps…I suppose in the near future it will have whatever voice Siri or Alexa or Grond, Warhammer of Morgoth, whatever floats your boat.
- The electricity bill is a lot more variable now—the cold spell in January meant a $200 electricity bill (first winter all-electric, and I only have just under half my solar PV installed). Still less than my neighbor’s $380 gas bill, which they got on top of their electric bill!
- Gas bill is $0 ad infinitum. A consummation devoutly to be wished (just reread Hamlet, wordy and wonderful low-carbon Dane).
- Some of the benefits of decarbonization are qualitative: the psychological sense of security in a more resilient building, comfort, and the beauty that is incorporated in design and finishesl. Physical and mental health are mutually dependent.