Embodied Energy of drywall
As a contractor, in an effort to reduce the embodied energy in the projects I work on, I have always encouraged my clients to avoid foam insulation where possible and minimize the use of concrete where practical.
Recently I have been involved in a design process with an architect who has argued that the embodied energy in gypsum board drywall is enough to overshadow the differences between different types of insulation(for example, foam vs. cellulose).
Since my clients would like to have drywall on their walls, but also minimize the carbon footprint of their project, I would like to be able to verify or refute this argument. It has also made me wonder if the carbon footprint of drywall gets relatively little attention from the green building community because the alternatives are largely incompatible with conventional building techniques.
I have not found a resource which puts this information into a meaningful context for me, but I am eager to hear opinions on the matter and happy to be pointed towards information which will help me put the embodied carbon of drywall into the larger context of the entire project.
Thank you!
Jason MacArthur
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
Hi Jason,
The most comprehensive source for embodied energy info that I've come across is the ICE database: https://circularecology.com/embodied-carbon-footprint-database.html
From their summary table, [gypsum] "Plasterboard" has an embodied energy of about 0.39 kgCO2e/kg, while an insulation like EPS foam ("Expanded Polystrene") is 3.29 kgCO2e/kg. For the purpose of this comparison, we might as well keep it mostly metric..
From the CertainTeed drywall website, 1/2" thick drywall weighs 7.8kg / sq. meter, so:
0.39 kgCO2e/kg * (7.8kg/m2) = 3 kgCO2e / m2
The density of EPS foam seems to vary quite a bit (10-35 kg/m2), but for a 1" thick layer:
3.29 kgCO2e/kg * (30kg/m3) * (1m/1000mm) * (25.4mm/inch) = 2.5 kgCO2e / m2 / inch
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So the embodied energy of 1/2" of drywall is approximately the same as a 1" thickness of EPS
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Lots of good articles comparing insulation types, such as:
https://www.greenbuildingadvisor.com/article/choosing-low-carbon-insulation
My take-aways (EE = embodied energy):
- EE of drywall > EE of cellulose based insulation (b/c the latter is negative)
- EE of drywall = EE of fiberglass insulation (very approximately)
- EE of drywall < EE of foam insulation (and sometime very much less)
Can you find USG ecosmart panels in you market?
They claim 25% embodied carbon reduction, reduced weight and other sustainability benefits.
Not sure about the cost difference