Day 25 - more concrete

When ordering the concrete we specified that we needed a conveyor, so that we could reach as many of the perimeter footings and as much of the holes in the concrete block walls as possible. We anticipated this being a slow tedious process, and had a trailer ready to take a load of concrete to fill some of the walls by hand. But we really lucked out.

The concrete truck driver/operator ended up being a friend of Pat's from his home town! He ended up spending over 2 hours methodically placing small amounts of concrete exactly where we needed it. Pat was even able to leave the site to go to most of his daughter's 2nd birthday party.


Pat made this hopper, with removable sections, that made the filling of the holes in the concrete block wall very easy and clean.

All of the holes in the wall that had rebar were filled with concrete to create vertical posts/beams within the wall. This strengthened the cross fin walls that carry most of the lateral wind loads in the two houses. We also filled holes points ever 900mm along the long walls, into which we inserted threaded rods with washers welded to the ends which were spaced in pre-drilled bearing plates.



Once set, we will remove the bearing plate, and put on a damp-proof course between the blocks and the wood. The ground floor structure will be bolted to the foundation wall.

Day 23 - pier foundations

Today was another slow day, frustrated by weather and waiting for material delivery.

The plywood for the ground floor structure and the roof arrived, much more plywood than I thought we would use, but it is providing the main stabilizing structure for the house.


With all the rain and wind we have been gettign lately, We made sure it was wrapped up tight.


We cut and bent the rebar that will tie the piers to the footings, and tied them into position. Apart from the bolts and bearing plate for the main walls of the cellar, we are now ready for the next load of concrete.

Day 21 - rebar in pad foundations

Another partial day on site - a lot going on these days and it is hard to get in a full work day. The next load of concrete is not coming until next Tuesday, so we have not been pushed.

Pat was able to cut up all of the rebar mesh for the pad foundations, and we set up all of the pads. Once we get the vertical rebar bent and in place (which will tie the concrete block piers to the concrete pad) we will be able to

Day 6 - concrete

The start of the concrete pour - made with Ecocem GGBS cement.

To fill the main foundation we needed 2 truck deliveries, and a fair amount of moving the stuff around.

This is what 14 cubic meters of concrete looks like (at 30cm deep). Two phrases come to mind - "over-engineered" and "ecological footprint". Ecocem is better than typical concrete, but it is still not good enough.

Frames of rebars were assembled and inserted into the wet concrete once it was leveled. These vertical rebars tie the footing base into the vertical walls of hollow blocks, the holes then filled with concrete to make one continuous structure for the base of the building. This was seen as necessary to deal with the horizontal and racking loading of the building (primarily from wind), and it allows us to use less structure on the perimeter of the two houses.

Robbie the donkey came for a visit to see what was going on.

The completed primary slab, with vertical rebars in place.

View of one of the cellar rooms with rebars for the perimeter wall and the structural fin walls.

Day 6 - finished formwork

A 6 am start this morning shows the work we finished in the dark last night - the two plastic sheets lining the pit. Unfortunately we had to slice the plastic to work it around the cross bracing of the formwork.


Two layers of mesh rebar in place, with. an additional 11 lengths of rebar was placed on the lower layer of mesh to add more strength to the slab over the softer patch in the centre of the dig.

The finished formwork ready for concrete.

Day 5 - preparing for concrete

In anticipation of concrete being delivered tomorrow morning, a lot of work needed to be done preparing rebar, building the formwork and fitting the plastic lining.


While the main rebar for the concrete base is going to be a series of 4.8m X 2.4m sheets (with very little cutting) we needed rebar lengths that were cast into the base and rise up through the hollow concrete block walls. This rebar was cut to length and then bent with a the help of an anvil a sledge hammer at first and then later with a steel pipe, which was a significantly faster and quieter method.


We built the formwork for the concrete, then back filled behind it (to prevent it moving with the weight of the concrete) by positioning a sheet of plywood at the top of the form work and chipping away at the top edge of the excavation with a pick/shovel. Tough work only because the soil is so hard.


We finally got the two sheets of builders plastic into the base just as it was getting too dark to see.