This amazing bit of building technology was inspired from medical casts used to immobilize limbs. This Concrete Canvas Shelter shows up packed flat in a waterproof plastic bag. You simply fill the bag with water, soaking the concrete infused canvas, and then inflate to make a permanent structure. This concrete tent hardens in about 24-hours and is then strong enough to stand on, is fireproof, waterproof, and possibly zombie-proof.
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