We prepare the area and the foundation before the workshop participants arrive.
The area planned for the new Roundhouse Dome is tucked in the north west corner of the property and we are going to have to take down this jungle ficus tree to make room for it. There are many of these trees that grew up spontaneously on the property. Unfortunately the fruit is not edible for humans, birds or animals and the wood is very soft and breaks easily. As you can tell, I am trying to justify cutting down a tree!
With the tree gone (leaves to compost, branches to the edges of the property to form swales to trap rainwater run off), there is now enough space to prepare the foundation. The top soil is moved off, and the ground levelled which includes cutting into the sloping hill. Then the posts that will hold up the roof go in. These are hard wood posts, and they will be visible inside the finished building.
We are going to do something a little different and continue the concrete base out from the edge of the building so that any rain splashing from the roof will drain away easily. This means that the outside 70 centimeters of the base will need to slope down a centimeter. Thus the concrete base will not only protect us from voracious termites, but also from the rain which can soften the earth around the building causing the building to move, and crack.
There was a village temple fair the week before the workshop and all the workers disappeared leaving just two or three of us to panic and amazingly manage to get the foundation finished literally the day before the participants arrived! We were still curing the cement as the building began, washing it down with water early morning and in the evening after we had finished working.
The height and shape of the dome is created with 3 strong pieces of rebar (reinforced steel) going across from post to post. Once we have the placement where we want, the rebar is attached to the wooden posts and we begin to weave the lighter rebar and bamboo to form the frame on which to attach the bags of rice husks.
Everyone had a go at cutting and harvesting the bamboo from a neighbour’s field. Then the bamboo needed to be cleaned and split. Good practice for using machetes!
While a few intrepid people worked up on weaving the frame up in the dome, the others worked on the frame for the walls.
Windows and doors are added at this stage. These can sometimes be quite tricky as the walls will eventually be about 30 cm thick. In the other domes the bags were added to the inside of the birdcage, so doors and windows were easily included in the main frame of the ‘birdcage’.
In this dome, because I want to be able to see the wooden posts inside the room when it is finished, the bags are going to be added to the outside, meaning our doors and windows need to be 30 cm out from the frame. We make box like wooden frames, and embed the up-rights into the concrete floor.
In the above picture you can see the first of the bags going in, and the up-rights of the wooden frame surrounding the window and door embedded into the concrete floor.
Participant Jules undertook the challenge of creating an opening for my various dogs and cats to come and go without me having to open the door for them, and without cutting into the lovely second hand doors that I bought for what will eventually become my bedroom dome.
Once all the bags have been attached to the frame, the next step was to learn how to make the mix of mud, rice husks and sand which forms the base of the plaster for the walls. We add a little lime into this mix too, to make it stronger and insect resistant. When there are large gaps between the bags we use straw coated with our mixture to plug them.
The only limitation to additional artistic features is your imagination!
In order for the participants to experience mixing and applying a final fine lime plaster, we used the walls of another almost completed Roundhouse, which you can see below.
This plaster is mostly lime, which has been sifted and soaked for a few days, and then finely sifted (though a mosquito net sieve). Then earth and sand is added for colour, and a dollop of sticky wheat paste (flour cooked in water).
This is a very different experience to the application of the previous heavier plaster mix, which can be applied by hand. Now we need to use a trowel and focus on getting the plaster smooth.
For more building experiences we went to another of the Roundhouses and learned to attach the frame for a shelf to a wall with bamboo stakes, and woven bamboo. This will be covered with plaster and will set very firm. I have lots of heavy books on my shelves!
We then learned how to make an earthbag bench that will be covered with plaster.
For more details on this and all the other processes, have a look back at past Blogs.
This is as far as we got on our Roundhouse Dome during the short time of the workshop. We did not continue to add the bags of rice husks to the frame of the dome, as we already knew how to do this and it would have taken a few days to complete the dome. We could not continue the plastering either until the plaster was properly dry. And so, as you have seen, we learned some other techniques to add to our store of knowledge and experience!
Some comments from participants:
Every day of building was not just a great learning experience, it was fun. Now I know that I’m not a complete idiot with a saw, hammer or machete (actually smiling about that right now) and it has given me a lot of confidence in my building ability.
Jules, from UK, living in Macau
Now I realise I can actually build something thanks to the hands on experience. Mark from Australia.
Thanks so much for sharing your knowledge, time and passion for rice husk building, and your philosophy of building as art. It was a wonderful experience!
Martin from the US, living in Indonesia.
Wonderful news! The Second Rice Husk Bag Workshop will take place 3 – 13 November 2015!! This time we will be building a Women’s Community Centre in a village of Kachin refugees in northern Thailand (near Arunothai). Come and join us!! Tell your friends!!