Honey, why do you throw away the concrete? - 捨てコン

In Sydney it is quite common to form the foundation of a building with piles. In Japan, the soil settlement across the site is a lot more stable, hence a shallow foundation system was employed for M House.

(for the curious...piling is a form of deep foundation to deal with poor soil condition at shallow depth, read more about it HERE; Sydney has relatively sandy soil which is not so good for building foundations, read more about it HERE)

In order to set up a precise base to proceed onto further construction, a step in site preparation called "捨てコン" (read: "sutekon", meaning "concrete to throw-away") started the day before yesterday on M House site.  It is an important step in early phase of the construction, to provide a good level surface to accurately setout the building from the beginning.  It is not for structural strength.

A general run-down of "sutekon" (across 2 days).....from Japan with love......

Day01 Step01- removal of excavated soil from site

Day01 Step02- pouring in crushed rubbles

Day01 Step03- Levelling out the crushed rubbles

Day01 Step04- Compressing crushed rubble

Day01 Step05- confirming compressed rubble thickness

Day01 Step06- site condition at end of Day01

Day02 Step07- service piping and conduit embedment

Day02 Step08- laying waterproof membrane over crushed rubbles

Day02 Step 09- pouring thin layer of concrete (normally 30-50mm) over the waterproof membrane

Day02 Step10- double checking concrete thickness

Day02 Step11- voila! now we have a smooth surface to accurately setout the building