We bury a scandalous amount of concrete in this country to prop up our buildings. I was keen to ensure that our structural engineer came up with a ‘creative solution’ to mitigate the amount needed, as we have had to go so deep to ensure we are below the level of the sewer. The concrete ‘pipes’ seems a good solution and getting hold of the steel ducts was a good find by the contractor. The picture above shows one of the four ducts for the founding ‘moulds’ placed in-situ ready for the concrete pour. In total, we need 2.5m³ of concrete as opposed to 8.75m³ with a traditional deep trench fill, a saving of 70% of grey stuff.