Just to confirm the utility of straw bale construction, I partially designed and have lived in a straw bale house for the last 25 years. It is a post and beam structure, with infill straw bale walls, and R-50 attic insulation of blown in cellulose. I bought the bales directly from a local farmer, wheat straw, and there are no signs of any problems, inside or outside. It is not perfect. I could have used a less embodied energy stucco on the outside, and the concrete floor is smooth, but not pleasant in the winter, though it is not so cold here as Canada (Shenandoah Valley Virginia, USA). In our state, as in most, state building inspectors are only slowly grasping that alternative building materials might be better, and local building materials best. Straw is not that hard to find, but getting the farmer to make extra tight bales might get tricky. Overall we are happy with the result.
In the past perhaps, but a hemp SIP wall would be much more effective if you compare the two side by side. A straw wall could combust with a strong fire while hemp does not. Shorter grow season for hemp and less fertilizer if any. Great startup industry, would utilize all parts of hemp. Straw better used for agriculture purposes.
Why do you say straw could combust? They are typically very dense and very low fire risk.
Hempcrete is usually much higher carbon impact than straw due to the amount of lime used and lower R-value for the same reason. So it would be interesting to see a like for like comparison across a range of performance metrics.
I'm wondering how straw may be dried, as any moisture, either within the construction or from humidity inside the building, may lead to mold and mycotoxins. So, while the dwelling is warm/cool, it may lead to serious long-term health issues. Alas, it may not be as hazardous as the off-gassing of petrochemicals and microplastics.
Usually it’s dried in the field and straw is just the stalks, not the leafy material that go to make up hay. So there is very little material in straw that can absorb moisture or is susceptible to mould.
Thanks for the mention, Lloyd. Credit to Jonathan Holmes at VIA architecture for crunching the carbon numbers that I used for the analysis and report for Hiberna.
I have seen video programs both streamed and on broadcast that show straw bales used as the core for adobe walls in the American Southwest as well. I don't recall whether this was a modern technique or a revival of far older practice in the region.
I am in the early stages of planning a stacked fourplex for my family. 2x 2 bedroom, 2x 3 bedroom stacked units with single stair. I want to build with straw SIPs but there are none available in Ontario. The best option I have found is https://www.croft.haus/ in Maine. I reached out and they will ship to Canada but it is frustrating that none exist here.
Just to confirm the utility of straw bale construction, I partially designed and have lived in a straw bale house for the last 25 years. It is a post and beam structure, with infill straw bale walls, and R-50 attic insulation of blown in cellulose. I bought the bales directly from a local farmer, wheat straw, and there are no signs of any problems, inside or outside. It is not perfect. I could have used a less embodied energy stucco on the outside, and the concrete floor is smooth, but not pleasant in the winter, though it is not so cold here as Canada (Shenandoah Valley Virginia, USA). In our state, as in most, state building inspectors are only slowly grasping that alternative building materials might be better, and local building materials best. Straw is not that hard to find, but getting the farmer to make extra tight bales might get tricky. Overall we are happy with the result.
In the past perhaps, but a hemp SIP wall would be much more effective if you compare the two side by side. A straw wall could combust with a strong fire while hemp does not. Shorter grow season for hemp and less fertilizer if any. Great startup industry, would utilize all parts of hemp. Straw better used for agriculture purposes.
I will look into that. Is anyone doing it?
https://thetyee.ca/WhatWorks/2025/02/03/High-Hopes-Hempcrete/?utm_source=weekly&utm_medium=email&utm_term=builder
https://justbiofiber.com
hempcrete.ca
https://www.hempbuildmag.com/home/new-hemp-building-directory-2024
Why do you say straw could combust? They are typically very dense and very low fire risk.
Hempcrete is usually much higher carbon impact than straw due to the amount of lime used and lower R-value for the same reason. So it would be interesting to see a like for like comparison across a range of performance metrics.
I'm wondering how straw may be dried, as any moisture, either within the construction or from humidity inside the building, may lead to mold and mycotoxins. So, while the dwelling is warm/cool, it may lead to serious long-term health issues. Alas, it may not be as hazardous as the off-gassing of petrochemicals and microplastics.
Usually it’s dried in the field and straw is just the stalks, not the leafy material that go to make up hay. So there is very little material in straw that can absorb moisture or is susceptible to mould.
Thanks for the mention, Lloyd. Credit to Jonathan Holmes at VIA architecture for crunching the carbon numbers that I used for the analysis and report for Hiberna.
I will!
Are there concerns about increased risks of molds w this type of construction?
I have seen video programs both streamed and on broadcast that show straw bales used as the core for adobe walls in the American Southwest as well. I don't recall whether this was a modern technique or a revival of far older practice in the region.
I am in the early stages of planning a stacked fourplex for my family. 2x 2 bedroom, 2x 3 bedroom stacked units with single stair. I want to build with straw SIPs but there are none available in Ontario. The best option I have found is https://www.croft.haus/ in Maine. I reached out and they will ship to Canada but it is frustrating that none exist here.