I had naively assumed that they just came one day and put down some steel reinforcement then poured the next day. Not so at our house! After about four days of them leveling and digging a massive delivery of polystyrene pods turned up followed by an, equally huge, quantity of steel and bags and bags of plastic do-dads and accessories to join everything together. Several more days passed while this lot was put in place before the day of the big pour arrived.
We sat and twiddled our thumbs while three whole cement lorries full were pumped down under the house. Being a concrete contractor must be stressful, especially on pouring day because once the pour starts, it cannot be stopped until the whole job is finished. So there were about eight guys running around down there with various flattening, smoothing and vibrating tools while another couple manned the pump and another one leaned on his concrete lorry, smoking. At one point the cement lorries were queued down the street and all we could do was peep down from upstairs as even offering a cup of tea would be getting in the way. We were exhausted when it was all over, watching and worrying was far worse than all the physical work we have been doing. 
Once it was over, things really began to take shape. The builder arrived and within a day of him starting, the back of the house was ready for windows and starting to look like a proper building. Now, after a week, we actually have some rooms too! Luckily the concreting was over by the time a group of visitors arrived although they did have to put up with the hammering, sawing and early starts from the builders.
