The old saying is that a picture is worth a thousand words.  Well, here’s a picture showing wasted energy:

The primary culprits here are window and door frames, and double whammy for the glass portions of the door, but this house appears to be well-insulated overall.  You can check how drafty your house is with the thermal imaging camera available at the Ashland Public Library.  I borrowed it this past January, and on a 35 degree day, found a few interesting leaks: even though my windows are double paned (and thus considered “efficient”, maybe even Energy Star rated), the gap top and bottom frames was reaching temperatures as low as 38 degrees because of some worn insulation.  I also found that, even with the flue closed, my chimney was also letting outside 37 degree air circulate.

While I haven’t yet replaced the windows or sealed the chimney, seeing the extent of cold air infiltration lead me to call Mass Save to schedule a contractor to perform a free home efficiency audit.    The contractor found that my attic insulation level was about standard for 20 years ago, but close to half the current standard for new construction. 

3 weeks later, I had the contractor air seal the attic, add another 8 inches of insulation, and fill empty space in an exterior wall which had previously had an issue with frozen pipes due to insufficient insulation.  Total cost was about $4500, but after Mass Save rebate, $1200.

I can report that my house was much more comfortable this summer despite extended stretches of high humidty and a few heat waves.  My heat pump seemed to be consistently at a lower operating level, often only running to dehumidify rather than actively cool.  Hoping that I see similar results this winter! 

When we lived in Maine for almost a decade, we lived in a super-insulated house that had 2 walls of 2X6s, effectively a foot think wall, filled with fiber glass insulation. It was heated with a single wood stove. It had solar hot water and windows facing South but no solar panels. The effectiveness of the insulation was amazing so, when we built our house in Ashland we did super-insulation, South facing windows and solar panels. In addition, we put in a wood stove and heat pumps, both to heat the house and for hot water. As my wife says, we pay for water and trash and nothing else. Indeed, Eversource owes us a lot of money because we generate much more electricity than we use. One extra expense is that, because the house is so tightly sealed, we have to run an air-exchanger so that the air does not get too stale. An air exchanger brings in outside air through piping that is right next to the indoor air being exhausted. The result is over 50% of the heat in the outgoing air is transferred to the incoming air. A neat trick