Algae-based blocks could make for a more sustainable building
newatlas.com
newatlas.com
There are also interlocking blocks that don't require mortar.
Lime for hempcrete can be made from algae.
"Eco-Friendly Construction Breakthrough: Lego-like Hempcrete Blocks That Don't Require Framing" [with Hempwood or spec pine] https://news.ycombinator.com/item?id=37643102
There are Structural and Non-structural {brick, concrete, hempcrete, sargablock, CEB Compressed Earth block} construction products and methods with varying levels of support in varying building codes.
"IRC Commentary Submitted to International Code Council" (2023) https://www.hempbuildmag.com/home/irc-commentary :
> The Hemp Building Institute, in partnership with the US Hemp Building Association, completed the final steps to include hemp-lime in the US residential building codes this summer.
> The new International Residential Code will be updated starting in January, 2024. States and building departments can adopt the code or parts of the code.
The US Farm Bills were good choices.
"Zero energy ready homes are coming" https://news.ycombinator.com/item?id=35060298
"Ask HN: Why don't datacenters have passive rooflines like Net Zero homes?" https://news.ycombinator.com/item?id=37579505
> This bio-cement was made from biomineralizing cyanobacteria that are grown using sunlight, seawater, and CO2.
> The blocks were created by mixing this bio-cement with aggregate to create a low-carbon building material with mechanical, physical and thermal properties comparable to portland cement-based concrete