Straw Building Blocks Make Warm Sustainable Homes
I’ve covered other straw bale construction techniques here before. This machine for tying straw into tubes on the field to build with, and these prefabbed walls of straw from a British company that stuffs straw into prefabbed wall-sized units near the farm…
…but these are the first straw bale building blocks I’ve seen. What a simple, but great idea. Straw bale construction is eco friendly. Straw is a waste product on farms. And sourcing your building materials from what would otherwise go to waste makes for very sustainable buildings.
Here’s how it works. Oryzatech has found a way to compress rice straw into interlocking blocks of super fire-resistant straw. The holes act both as stabilizer connectors, just like lego blocks, but also provide the conduit through which threaded rods run to bolt the walls to the foundations, and to allow vertical runs for electrical, plumbing and cable conduits.
Through a scalable, low energy-production process, the company can make and sell an almost unlimited supply of highly insulating, carbon-sequestering construction blocks.
The insulating value of straw is unparalleled. The resulting structure creates (Passive-haus level) R-50 insulating walls, that provide better shear strength than a traditional sheathed 2×4 wall.Â Each block weighs about 30 pounds, and is easily clean cut with a saw. California Polytechnic University has tested the blocks and found that they are:
- Highly insulated: More than three times the value of an insulated 2X6 stud wall
- Seismically strong: better than wood framing and less brittle than concrete walls
- Fast to assemble: Block dimensions are 12â€x12â€x24â€, easily dovetailing with other common construction modules. Each block weighs only 30 lbs and interlocks.
- Carbon Offsetting Technology– University testing shows potentially 50 lbs of carbon offsetting
With all these positives, there is just one negative. No horizontal conduit runs are possible so far. The vertical hole is available in every block, so the fact that these are not available with conduit holes that also enable horizontally run conduit matters somewhat less; however, this is one thing the duo are working on finding the resolution for, because obviously it is still an issue. Though you could design around this, with a horizontal wooden beam to contain the horizontal runs at some point up the wall.
This is a sketch of the idea, at this point, there’s no release date announced, and the two are looking for investors…