Retrofits have a significant problem with cost, both to improve the building envelope and to reduce operating costs. If the environmental impact of a retrofit is better than a demolition and rebuild, but the cost of doing so to the owner is too high, then what? Should we subsidize renovation? How do we find the sweet spot between a very costly deep energy retrofit and a less thorough one that reduces future carbon emissions by less?
Thirty years ago, we bought a 4000 square foot, 200+ year old house. Over the years, we spent a lot of money maintaining it, while only marginally improving its energy efficiency. It was too big and costing us $6-7000 per year in fossil fuels to heat. In 2015, before we understood the problem of upfront carbon, we sold the house and built a new, 1650 square foot, very energy efficient house. Knowing what we now know, what would have been the better course, a pretty deep retrofit to save future carbon and annual cost, or building new?
It's a complicated question because you can't consider just your own actions--had you stayed put, what would have the person who bought your old house have done? Buy a similar old house? Build a 4000 sq ft passive house? Build a 4000 sq ft code-min (or worse, because inspection is spotty or nonexistent) house?
Source check - I believe you need to credit the graph to a different publication, not World Green Building Council. I see a lot of circular references on this graph and it looks like it goes back to:
Opportunities to reduce embodied carbon reduces as the project progresses (Decarbonizing construction, 2021, World Business Council for Sustainable Development)
If the upfront carbon problem is as urgent as you say, then historical preservationists need to get with the game and stop opposing exterior insulation. It is the best way to lower both operational carbon emissions and preserve the structure of the building, which delays upfront carbon emissions further into the future. If it's worth sacrificing comfort and money to avoid emissions then aesthetics are also worth sacrificing.
Great presentation on Saturday. It is inspiring me to ask my municipality for council to go back to approving demolitions -- and a chance to delegate and share some of this information about why they should not automatically approve all demolition applications.
Projects that are unacceptable today due to upfront carbin will move towards acceptability in the future as improvements in green technology and architecture reduce the upfront carbon of the projects.
Very clear and well crafted, Lloyd, as always! One thing I've been grappling with in the past couple years is the huge amount of *new* upfront carbon that cycles through during operations. Especially all those commercial fit-outs (changing out carpet every two years, ugh). And major mechanical system components also get replaced a few times during the 50-year life cycle. There's precious little data so far on the baselines here, but the "upfront" carbon of many building typologies is not anything like a straight line over 50 long years. So ... even more important to reduce and reuse.
Retrofits have a significant problem with cost, both to improve the building envelope and to reduce operating costs. If the environmental impact of a retrofit is better than a demolition and rebuild, but the cost of doing so to the owner is too high, then what? Should we subsidize renovation? How do we find the sweet spot between a very costly deep energy retrofit and a less thorough one that reduces future carbon emissions by less?
Thirty years ago, we bought a 4000 square foot, 200+ year old house. Over the years, we spent a lot of money maintaining it, while only marginally improving its energy efficiency. It was too big and costing us $6-7000 per year in fossil fuels to heat. In 2015, before we understood the problem of upfront carbon, we sold the house and built a new, 1650 square foot, very energy efficient house. Knowing what we now know, what would have been the better course, a pretty deep retrofit to save future carbon and annual cost, or building new?
It's a complicated question because you can't consider just your own actions--had you stayed put, what would have the person who bought your old house have done? Buy a similar old house? Build a 4000 sq ft passive house? Build a 4000 sq ft code-min (or worse, because inspection is spotty or nonexistent) house?
Source check - I believe you need to credit the graph to a different publication, not World Green Building Council. I see a lot of circular references on this graph and it looks like it goes back to:
Opportunities to reduce embodied carbon reduces as the project progresses (Decarbonizing construction, 2021, World Business Council for Sustainable Development)
I will look into that...
My colleague found the earliest use of this graph is here: https://assets.publishing.service.gov.uk/media/5a7c9803ed915d12ab4bbd33/infrastructure_carbon_review_251113.pdf
this is marvelous I was just working on this! thank you
Happy to help from the Climate Team in Portland!
Yup, that is a really interesting document! and my next book just went to the printer with that in it with the wrong credit. I will see if I can fix!
At least WGBC is a partner in that report. Hope it works out.
If the upfront carbon problem is as urgent as you say, then historical preservationists need to get with the game and stop opposing exterior insulation. It is the best way to lower both operational carbon emissions and preserve the structure of the building, which delays upfront carbon emissions further into the future. If it's worth sacrificing comfort and money to avoid emissions then aesthetics are also worth sacrificing.
In old northeastern towns they can easily be more than 10-20% of the habitable units.
Great presentation on Saturday. It is inspiring me to ask my municipality for council to go back to approving demolitions -- and a chance to delegate and share some of this information about why they should not automatically approve all demolition applications.
Thank you Kae.
Projects that are unacceptable today due to upfront carbin will move towards acceptability in the future as improvements in green technology and architecture reduce the upfront carbon of the projects.
Very clear and well crafted, Lloyd, as always! One thing I've been grappling with in the past couple years is the huge amount of *new* upfront carbon that cycles through during operations. Especially all those commercial fit-outs (changing out carpet every two years, ugh). And major mechanical system components also get replaced a few times during the 50-year life cycle. There's precious little data so far on the baselines here, but the "upfront" carbon of many building typologies is not anything like a straight line over 50 long years. So ... even more important to reduce and reuse.
Architects for Climate Action handle this well on Page 12 of their report I should have put that slide in the post but I thought it would confuse the issue https://www.architectscan.org/_files/ugd/b22203_c17af553402146638e9bc877101630f3.pdf?index=true
Yes, it's always a mixed bag ... how much detail diverts from the main point. An occupational hazard. Thanks for the link! Love this document.