Thanks to some advice from Rowland at Ram Cast CIC, Form3 is free of bolts and hopefully a lot quicker to put together because of that. The design is based on the example here.
One mad dash to build a rammed earth house before the rains hit in April...
Thanks to some advice from Rowland at Ram Cast CIC, Form3 is free of bolts and hopefully a lot quicker to put together because of that. The design is based on the example here.
After the failed first test a number of lessons were learned: that the form needed to be stiffened dramatically to stop flexing, the areas around the bolts needed reinforcing and the form needed to be narrowed by a couple of centimeters to protect the edge of the foundation cap.
The materials of Formwork 1 were recycled to form the basis of formwork2. A new set of braces and brackets were fitted to the outside of the forms, and the clamps were replaced with pairs of through-bolts.
The formwork was constructed by local carpenters using a locally available pine. The design was based on a rolling formwork design by Middleton. After some delays finishing the form and the mallets the testing began. Because it was late in the day, low section of wall under a window was selected to be the test wall.
It was immediately obvious that the timber was too green and soft for the number of braces used, as it started to flex in between the clamps on only the first course. As the ramming continued the foundation cap began to chip-off in a couple of places. A second course was added to one end section that wasn’t flexing and, before it was rammed firm, one of the end bolts pulled through.
The rather paltry wall sample was left in place to see how it would fair in the elements and if it would firm up with time.
After an unseasonable period of rain and a broken foot, works are back underway. The foundation walls are finished and the spaces in between have been filled loosely with soil to provide a surface to walk on while the walls go up. The lose fill will be allowed to settle before being tamped down to provide a base for the floor.
First order of business was to rough in the floor drains and sewer pipes into the foundation wall. The small oversight of not putting these in while the foundation walls were going up was quickly rectified. Next a cement cap was added to the foundation walls to provide a level base for the walls and act as a bit of a moisture barrier. Gaps are visible where the eucalyptus poles are going to be fixed to the foundation.