I recently got an email from Sunny Tsai, a Chinese professor of architecture (now retired) with an update on a lovely meditation dome he and some 1400 Buddhist volunteers have just completed in Taiwan. He says that “To reach my idea of carbon reduction and sustainability, I avoided using all kinds of industrial materials and used only a minute quantity of cement. The dome is 6 meters in diameter. To people’s surprise, the interior space looks so wide and comfortable. It’s super cool and the Monks can enjoy the atmosphere of quiet and peacefulness. One summer day at noon we surveyed the temperature, and found a 6 degree (Centigrade) difference between the interior and outdoors.”
I have posted a page about this project at earthbagbuilding.com where you can see lots more photos of the dome being built.
How does one make the dome water-proofed?
Build a roofed dome or make a rain screen.
There are many approaches to making a masonry dome water-proof. First off, you should use as little water as possible in the concrete if using concrete. This alone should make concrete much stronger and denser.
Next, the concrete should be troweled as smooth as possible and then sealed with lime and silicate salts in multiple layers. Finally a variety of surface coatings can be used on the smooth, glassy exterior.
Hello, i am from India and would like to build an earthbag dome. Is it advisable to do so because we get around 3 months of heavy rainfall. How do we plaster the domes?
Domes evolved in deserts. You will have moisture problems in rainy climates unless you build a roofed dome or a rain screen.
Owen, would you say there is an optimal thickness size wall that will actually use thermal mass to one’s advantage in hot climates? Like facing with rock maybe as exterior insulation.
Most earthbag domes use standard 18″ bags. Large domes use standard 24″ bags.
Stone is thermal mass just like earth so stone will not insulate the dome. But you can possibly add an insulating layer with stone on top. There are many options.
I love the idea of these but a 6° difference in Texas, when it’s 110° outside, would not make much difference here. A friend just completed a Cobb house here in North Texas and he’s having a real problem cooling it. Once all of that mass heats up, it stays hot for a long time. :(
Yes, we have warned of this before. Every design must be adapted to the climate in which it is built. Deserts cool down a lot at night so the earthbags do not tend to overheat in the day due to the ‘thermal flywheel effect’. But Texas is different than the deserts in say the Middle East. Earthbag domes in Texas would tend to overheat without additional protect. Roofed domes are a good solution. I have a new blog post about roofed domes coming soon.
Also, keep in mind the 6 degree difference is in centigrade, not fahrenheit.