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Comment by justaaron | Hacker News Reader

of COURSE the Beeb isn't taking comments upon this article. I built a "super-adobe" or "earthbag" house, here in Portugal. It was utterly destroyed by the bush fires of 2017, and I do not recommend this technique for multiple reasons:

1)no structural integrity to the actual fill of the bags, unless you add cement, in which case why are you building with earth bags?

2) poly bags are very un-eco, as I'm still cleaning up the remains of my house. It degrades under UV light and many bags burst before being rendered even, and had to be replaced.

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I'm sorry you lost your house. I never built rammed earth or pise or any related technology, but I have read about it from the 70s and I always assumed it had significant structural integrity from beams and posts, alongside the main material.

If the fire was hot enough to consume these, or if roofing caught fire and then it burned 'down' It may well be the fire was un-survivable for almost any form of construction except steel and concrete.

What was your roof? How big were your eaves, and how close was the surrounding bushland and trees, which I assume (since its portugal, and they planted a french metric tonne of eucalypts, which is a very very hot fast fire) was the primary risk?

Did you try and 'stay and fight' or evacuate? Here in Australia its a high risk decision: Stay and die, or leave and lose the lot but some people stay and survive at significant personal risk, designs are out there to provide shelter, and techniques in hazard reduction but if the fire is big enough, you lose.

I think this form of building remains interesting because of the thermal store and low(ish) cost but I am now thinking about what you say, because I really thought it had more fire survivability than you seem to be suggesting.

I don't understand the relevance of your first sentence... are you alluding to some kind of supposed agenda? Does BBC Future ever have comments on articles?

I've helped friends construct "earthbag" domes, but they used stabilized earth (lime in one, portland cement in another).

> 1)no structural integrity to the actual fill of the bags, unless you add cement, in which case why are you building with earth bags?

Because earth bags (or sand bags) are cheap and you can start building your structure in small increments immediately. There's no need for constructing forms, and you can mix stabilized earth in small batches. We're in the desert, so the fill was pretty ideal and didn't require much cement to stabilize.

My friends have their share of earthbag structure complaints but they're more focused on how laborious and time-consuming the process is, and the cost of protecting the exterior with something like stucco which you then can't really put loads on (like climbing/walking) without cracking.

They've since moved on to only making earthdomes below grade, where it's naturally cooler (desert) and you don't have to deal with an exterior finish like stucco, as it's all buried underground.

Aren't you supposed to cover the bags with more clay or stucco or something? Much like doing a cobb house. Cobb is fireproof, and earthquake resistant. Cobb also resists UV degradation. If you're leaving the bags exposed, that's wrong.

Yes. You're also supposed to used barbed wire and rebar to reinforce the structure.

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