Everyone knows about the impact of burning fossil fuels on global warming. Maybe not everyone believes it, but scientists first started focusing attention on increasing carbon dioxide levels way back in 1827. The impact of insulation on global warming, however, is relatively new.
About a decade ago, Professor L.D. Danny Harvey started looking at the effect of blowing agents released by the production and use of some foam insulation types. Then Alex Wilson picked it up in 2010.
At the 2016 North American Passive House Conference, I presented my views on this topic. I wrote about the first part of my talk in my last GBA article. Today, I cover the part about using David White’s global warming tool for insulation.
In his calculations, Alex Wilson chose one scenario. He looked at the global warming impact for a house heated with a natural gas furnace. He chose a cold climate with 5,000 heating degree days (HDD), and he didn’t include cooling.
The resulting payback showed how long it would take to save enough energy to offset the global warming emissions from the embodied energy in the insulation and from the release of blowing agents with global warming potential (GWP). He looked at several different insulation types and a range of R-values.
The first part of my conference presentation covered what I see as the main flaw with his payback calculations. In the second part, I discussed David White’s spreadsheet tool for calculating the global warming impact of insulation. The nice thing about his calculator is that you can change a lot of the variables and see what the effects are.
I showed three scenarios in my conference presentation. I’ll put them in a different order here, beginning with the gas furnace. If you download the presentation file, you’ll find…