Our plan was to start ramming the first wall on Monday morning but I have decided to play it safe. In casting the columns, we were busy manufacturing various sections that we needed as we went. How we did not make a bunch of mistakes is anyone's guess and there were a couple of close calls. The major lesson learnt is that every single thing needs to be checked twice before we accept it as correct. One corner column was nearly cast out of alignment because of our eagerness to get on with the job. So now we have set Monday aside to make all the bits and pieces we need to complete all of the walls. A key requirement is to print out the latest set of plans and to work from these - currently we are working from a variety of versions. Already over the weekend, I've discovered that the window openings as per the plan are smaller than the actual windows. So all openings now need to be made according to the actual window sizes and not to the architects drawing.
On Thursday we set up one section of formwork in preparation for the first rammed earth wall. We are working with perfectly level stem walls and columns which should by default make the rammed earth wall fairly plumb. In addition, each panel is screwed into the adjacent panel as 
shown on the right. Despite this, the panels at the top still bowed in. To prevent this, we have now made spacers to fit along the top of the panel sections which now means that we have 450mm spacers along all four planes. This has resulted in a very rigid structure and there is absolutely no chance of these walls being anything but plumb all round. So we have made our first list of things to do (playing it very safe) and Monday's tasks are as follows: - Paint on Damp Course - we're using a paint-on waterproofing membrane.
- Make Rakes x 2 - these are to spread the rammed earth lifts
- Make top spacing brackets x 9 (i.e. extra 6) - to prevent the forms from bowing in as per picture on the right.
- Make seat for formtop operator - we are hand ramming the walls and this person will coordinate the soil delivery, the colour mixes and keep all the implements clean.
- Step ladders for inside and outside of forms - for people to get in and out of the wall cavity.
- Finish facebrick and concrete infill between pillar and brick course - this is the final thing that is done to the stem wall before we are ready to set the forms for the wall.
- Build Chute x 1 - the bucket that will lift the mix is quite wide and we are going to build a chute to ensure all of the soil lands in the right spot and not all over the place. 300kg of soil landing on your head from 4m will do some serious damage.
- Build base panel for the 925 wide x 2400 high window x 2 - this is a simple way for us to sort out the window ledges. Rather than making a complete volume displacement box, we are using a simpler method that gives us more flexibility, a better finish and a better braced endboard.
- Build endboard panels for the 925 wide x 2400 high window x 2 - these are the vertical panels which will form the wall edge for the windows. Hopefully by spacing them the exact width of the windows and bracing them properly will make installing the windows a doddle.
- Build base panel for the 1350 wide x 3600 high window x 4 - same as pt.8 above but for the wider window.
- Build endboard panels for the 1350 wide x 3600 high window x 4 - same as pt.10 above but for the taller window (3.3m high)
- Arrange small hand stamper - this is to get into the hard to reach places.
- Purchase 45 deg plastic inserts: 12 x 3.6m - this is to create the chamfers on the walls. We hand made the ones for the columns but we are going to use off the shelf plastic ones for the rammed earth work.
- Sort out Chalk Line - to mark the levels on the forms for the coloured lifts and endboards.
- Purchase buckets for lime, stone and water - this is to ensure that we have a standard mix every time. The idea is to measure out the first few and then have a standard measure for each item, which will be a bucket with a mark on it that reads "Fill to here".
- Submersible water pump - this we will use to pump a standard measure of water into the mix.
- Permanent markers for drawing lines on shutterboard & for labelling buckets
- Weigh all the lime that has been delivered & mark the bags - we've had bags of lime supplied and these are in different sized bags. We need to weigh them all so we are not paying for lime that has not been delivered.
- Arrange plastic to to cover all rammed earth walls for a 5 day curing period.
Things to work out on Monday:
- Define a set of safety rules - especially for the formtop operator.
- Work out how to mark & install keyways where brick walls intersect rammed earth walls.
- Work out how to mark & set out endboards (Volume displacement box) where windows are to be installed.
- Work out a simple mechanism to load the correct amount of soil into the hopper according to the length of the wall. Note: The maximum finished 'lift' size - the height of the compacted layer is 12cm. The maximum uncompacted layer should therefore not be more than 15cm but I feel we should reduce this to 12cm. When putting in a coloured line, the lift should be 6-8 cm for a coloured line, preceded by a 6cm uncompacted natural lift to achieve the wavy (not straight) finish.
Coloured Seams: Coloured seams must be placed at the following heights above the stem wall:
- 150mm Red
- 850mm Red underneath/Black above
- 1800mm Black
- 3000mm Black
All seams must be made to look natural (i.e. no straight edges). This is achieved by sandwiching a coloured lift between un-compacted lifts of a different colour. Note that the surface of all lifts must be made uneven before the placement of the next lift. Compaction of the sandwich of lifts is then performed. Note: 1 kg of oxide per wheelbarrow of soil must be used.
Once all of this has been done, then we should have a set of formwork (excluding walers) that looks something like this:
And inside the form, it should look something like this:
And we'll all have to wait and see what the wall looks like.....
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