I've been objecting to this for a while due to the misleading word embodied. I've been putting carbon in three (and a half) categories: Material production emissions, operating emissions and sequestered carbon. (I can't decide between calling them material or production, so just use both for now.) Production emissions can be upfront (that's the 1/2 of the 3 1/2 categoresi) but also occur during the life and end-of-life of the building, which would means they're not 'upfront.'
The emissions related to products & materials that occur during the life and end-of-life of buildings (modules B & C) are still “upfront” in that they are *already emitted* by the time the material or product is used/installed in the building. “Upfront” refers to this fact as much, or more so, than where they occur in the building lifecycle. (As opposed to energy and water use, where the emissions happen, roughly speaking, while they’re being used, not beforehand.)
Yeah, certainly in the construction industry we are used to thinking of emissions in terms of the building life cycle rather than specific products/materials. It gets quite tangled.
So many threads to pick at here! (And most of those threads wouldn't even exist if we all lived in a world of "sufficiency"). I'm not downplaying the importance of CO2 but it sure has eclipsed a lot of other issues. I lived in the woods in Nova Scotia for 15 years and got radicalized about what we have done to our forests. If we were intensively growing wood in small areas to harvest carbon and put it in buildings maybe that would be a net benefit but we are not doing that. We are absolutely raping our forests from coast to coast to coast. Same goes for hydropower. Great, it doesn't emit operational carbon but it's hardly clean. It destroys vast tracts of land and forest. And often, the areas it destroys are important to indigenous people.
An anecdote. I once built an addition for a friend. There was a beam in it that was about six times bigger than it needed to be. My friend was proud that all the lumber was FSC but I pointed out to him that I could build a whole shed out of the wood in that one beam! I'm with you Lloyd. SUFFICIENCY!
Also adding to the confusion, somewhat ironically, when biogenic carbon is claimed to offset carbon emissions, you get some architects “declaring their buildings “carbon positive”” and others declaring their building “carbon negative” 🤷🏼♂️
I think we need to distinguish between wood used as a building material, which typically requires harvesting trees and turning them into lumber, and building material like wood fiber insulation or OSB which use slash, chips and similar leftovers from making lumber. Those materials sequester carbon that otherwise ends up burned or composted and released into the atmosphere. The greater the proportion of a tree which ends up in a building, the better. Using 80% of a tree is probably better for the climate than using 40%.
I've been objecting to this for a while due to the misleading word embodied. I've been putting carbon in three (and a half) categories: Material production emissions, operating emissions and sequestered carbon. (I can't decide between calling them material or production, so just use both for now.) Production emissions can be upfront (that's the 1/2 of the 3 1/2 categoresi) but also occur during the life and end-of-life of the building, which would means they're not 'upfront.'
The emissions related to products & materials that occur during the life and end-of-life of buildings (modules B & C) are still “upfront” in that they are *already emitted* by the time the material or product is used/installed in the building. “Upfront” refers to this fact as much, or more so, than where they occur in the building lifecycle. (As opposed to energy and water use, where the emissions happen, roughly speaking, while they’re being used, not beforehand.)
True, but I think a lot people interpret 'upfront' to mean before the building is completed/occupied and operational energy kicks in.
Yeah, certainly in the construction industry we are used to thinking of emissions in terms of the building life cycle rather than specific products/materials. It gets quite tangled.
So many threads to pick at here! (And most of those threads wouldn't even exist if we all lived in a world of "sufficiency"). I'm not downplaying the importance of CO2 but it sure has eclipsed a lot of other issues. I lived in the woods in Nova Scotia for 15 years and got radicalized about what we have done to our forests. If we were intensively growing wood in small areas to harvest carbon and put it in buildings maybe that would be a net benefit but we are not doing that. We are absolutely raping our forests from coast to coast to coast. Same goes for hydropower. Great, it doesn't emit operational carbon but it's hardly clean. It destroys vast tracts of land and forest. And often, the areas it destroys are important to indigenous people.
An anecdote. I once built an addition for a friend. There was a beam in it that was about six times bigger than it needed to be. My friend was proud that all the lumber was FSC but I pointed out to him that I could build a whole shed out of the wood in that one beam! I'm with you Lloyd. SUFFICIENCY!
Also adding to the confusion, somewhat ironically, when biogenic carbon is claimed to offset carbon emissions, you get some architects “declaring their buildings “carbon positive”” and others declaring their building “carbon negative” 🤷🏼♂️
We are, actually, carbon based life forms. Can we used burned carbon, or waste carbon?
I think we need to distinguish between wood used as a building material, which typically requires harvesting trees and turning them into lumber, and building material like wood fiber insulation or OSB which use slash, chips and similar leftovers from making lumber. Those materials sequester carbon that otherwise ends up burned or composted and released into the atmosphere. The greater the proportion of a tree which ends up in a building, the better. Using 80% of a tree is probably better for the climate than using 40%.