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Startup Builds Houses by Pumping Concrete into Inflatable Forms

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Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#41

Post by olliej »

Hmmm, so I'm aware that a significant difficulty in normal concrete construction is ensuring that all the concrete gets everywhere it needs to go - and that's with relatively direct access a lot of the time.

I'm also not entirely clear what the saving is here - you still have to get concrete from somewhere to the construction site, to somewhere that presumably already has some local material that could be use instead?

Also if it's just making a box, that's not the problem - people have already have shelter. Where things break down are access to clean water, food, and similar. But I guess those don't sound sexy and so don't get funding.

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#42

Post by jeffrallen »

raisin_churn wrote: post #38

In what way is concrete a sustainable building material? It's a huge carbon emitter, a poor insulator, concrete production is devastating to natural habitats turned into sand quarries, etc. Plant-based construction materials, e.g. hemp, seem to be vastly superior on every ecological consideration. Plus, an unreinforced concrete dome has to be one of the inherently least population dense structures, and density potent…

You forgot to mention that PVC comes from oil, and is a health hazard.

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#43

Post by dieselgate »

lettergram wrote: post #22

This is fairly common with styrofoam. https://www.concretecontractornc.com/a-house-built-with-styr...

That's a cool link thanks for sharing. Seems pretty thermally efficient and they mentioned being quieter than wood walls. Curious what data they're looking at for "withstanding natural disasters"

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#44

Post by adwn »

ewzimm wrote: post #10
booi wrote: post #6

Earlier quoted context omitted.

Well concrete is not waterproof (generally) so they are technically also using the form as waterproofing. It's pretty clever IMO but you'd need rebar at the very least for any structure worth building...

Concrete construction without rebar is more durable and worth bringing back. https://en.wikipedia.org/wiki/Roman_concrete

Concrete without rebar lacks tensile strength, and Roman concrete is no different. When using materials with insufficient tensile strength, you're severely restricted in the kinds of structures you can build. That's why Roman buildings used so many domes and arches, and why they were massive.

Practical Engineering has a good video about it: https://www.youtube.com/watch?v=qL0BB2PRY7k

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#45

Post by inglor_cz »

francoisfeugeas wrote: post #30
mNovak wrote: post #15

Is concrete actually a good building material for homes? It doesn't seem like it'd be insulating, and you're definitely not getting internal plumbing/wiring. And concrete is actively bad for the environment. It all feels like the shipping container home -- seems great at a glance, but doesn't really pan out to be lived in. Ikea style flatpacked prefabs still seems like a vastly better option to me.

Well, the vast majority of Europe builds concrete homes. We definitely get insulation, internal plumbing and wiring.

Individual homes in Europe are typically built from bricks, with concrete used for foundations/floors/ceilings.

The work around internal plumbing and wiring is messy, though. A lot of abrasive brick dust is generated. I wouldn't want to be the guy doing this stuff. In a 3D printed home, nice empty spaces could be left in the wall while printing for all the necessary networks.

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#46

Post by defrost »

raisin_churn wrote: post #38

In what way is concrete a sustainable building material? It's a huge carbon emitter, a poor insulator, concrete production is devastating to natural habitats turned into sand quarries, etc. Plant-based construction materials, e.g. hemp, seem to be vastly superior on every ecological consideration. Plus, an unreinforced concrete dome has to be one of the inherently least population dense structures, and density potent…

While not sustainable concrete made from fly-ash locks up ongoing and historic waste from coal fired power stations.

We're phasing out our 60 year old coal station given the sheer amount of solar power we now generate in W.Australia - but we still have 60 years of fly ash to deal with.

[1] https://www.abc.net.au/news/2021-09-18/geopolymer-concrete-c...

[2] https://www.mediastatements.wa.gov.au/Pages/McGowan/2022/08/...

[3] https://colliecrete.com.au/

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#47

Post by raisin_churn »

jeffrallen wrote: post #42
raisin_churn wrote: post #38

In what way is concrete a sustainable building material? It's a huge carbon emitter, a poor insulator, concrete production is devastating to natural habitats turned into sand quarries, etc. Plant-based construction materials, e.g. hemp, seem to be vastly superior on every ecological consideration. Plus, an unreinforced concrete dome has to be one of the inherently least population dense structures, and density potent…

You forgot to mention that PVC comes from oil, and is a health hazard.

Indeed, although I suspect the PVC in the inflatable form could be replaced with some other, actually sustainable material. It's therefore an even bigger indictment of this company that they didn't even bother to do this and are somehow touting their process as sustainable.

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#48

Post by raisin_churn »

defrost wrote: post #46
raisin_churn wrote: post #38

In what way is concrete a sustainable building material? It's a huge carbon emitter, a poor insulator, concrete production is devastating to natural habitats turned into sand quarries, etc. Plant-based construction materials, e.g. hemp, seem to be vastly superior on every ecological consideration. Plus, an unreinforced concrete dome has to be one of the inherently least population dense structures, and density potent…

While not sustainable concrete made from fly-ash locks up ongoing and historic waste from coal fired power stations. We're phasing out our 60 year old coal station given the sheer amount of solar power we now generate in W.Australia - but we still have 60 years of fly ash to deal with. [1] https://www.abc.net.au/news/2021-09-18/geopolymer-concrete-c... [2] https://www.mediastatements.wa.gov.au/Pages/McGowan/2022/08/.…

Yes, fly ash concrete seems more sustainable than concrete without it (provided that the fly ash already exists) in certain applications where its particular properties are beneficial. I seem to recall it having greater durability under compressive loads, so roads can be built that require less frequent repair. In the US, we have enough roads falling apart I think we could use all the fly ash concrete we could possibly make, and we wouldn't have any extra to build substandard, energy-inefficient housing.

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#49

Post by imgabe »

raisin_churn wrote: post #38

In what way is concrete a sustainable building material? It's a huge carbon emitter, a poor insulator, concrete production is devastating to natural habitats turned into sand quarries, etc. Plant-based construction materials, e.g. hemp, seem to be vastly superior on every ecological consideration. Plus, an unreinforced concrete dome has to be one of the inherently least population dense structures, and density potent…

Yeah, replacing wood, which is a carbon sink, with concrete, which is a huge emitter of CO2, seems like a bad trade.

Re: Startup Builds Houses by Pumping Concrete into Inflatable Forms

#50

Post by ArchitectAnon »

The structural frame is easy. Stick frame, CLT, SIPs already exist and are better than this basically everything except a blockwork structure already takes less than a week. Insulation, airtightness and services integration is hard. Services takes way longer than the frame.
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