We were pleasantly surprised to see this earthbag water tank just down the road from a house we (Liz’s group) were building. The church group saw our project and on their own figured out how to use the same earthbag techniques to make their water tank. No plans, no technical assistance, nothing.
Earthbag Water Tanks
We’ve nearly finished an earthbag water tank with narrow tubes that cost $200 in materials. Plastic tanks this size retail for around $1,350 in Vanuatu, so this design costs far less than the main competing product. It won’t blow away in a hurricane, break down from UV rays or taint the water with plastic chemicals. Our water tank includes a domed ferrocement top that’s exceptionally strong. It can be built in 2-3 days by four workers with minimal skill, although plastering skill is very helpful. There’s a huge water shortage on the islands here in Vanuatu, as well as many other places. Those who learn this method could make a lot of money selling water tanks since demand is high and cost of labor is cheap.
On the Road: Live from Vanuatu
For decades it’s been my dream to visit developing countries and help build affordable housing projects. Now, here I am on the beach in beautiful Vanuatu to assist the Women’s Centre (and others) on various sustainable building projects.
“The biorock building process (called accretion) grows cement-like engineering structures and marine ecosystems, often for mariculture of corals, oysters, clams, lobsters and fish in salt water. It works by passing a small electrical current through electrodes in the water. The structure grows more or less without limit as long as current flows.
Ferrocement Rainscreen for Earthbag Domes
Domes evolved in deserts, so we recommend extra protection for snowy/wet climates. There are two main approaches: 1. Build a roofed dome. Search our Projects pages at Earthbag Building.com to see several examples. 2. Build a ferrocement rainscreen on the exterior of the dome. The rainscreen is basically an outer cement shell that’s built on top of the dome with about 1″ space between that allows any water that gets through to escape.
Below Ground Ferrocement Rainwater Tank
The lowest cost soil for earth building comes from the building site itself. Dig the soil onsite and you could build a ferrocement tank below ground in the pit.