Stanley Brash and his team of builders have moved unbelievably fast this last 2 weeks. Foundations are done and approved. Drains are done, tested and approved: “Perfect” no less from the building inspector. So now we’re ready for the concrete to be poured for our floor.
Preparing for this took all of Friday with 4 people working flat out in weather I’m learning to call “dreich”. That means cold and wet to the rest of the world. Downright miserable it was.
First of all, the area inside the foundations was scraped back as far as possible to the undisturbed soil beneath. This left about 15cm of soil from which we removed the bulk of the large river worn stones that prevail around here. Then along comes the thwacker to compress this first layer down. Stan was explaining how the thwacker exerted about 12 tons of pressure through a gadget no larger than a small lawnmower.
Next came a 15cm layer of hardcore – a mix of fine gluey soil and very small stones. And again the thwacker went round pressing this down. This happened twice. To give you some idea of how solid this becomes, we had just piled some up at the entrance to the site so delivery wagons didn’t just sink into the morass. We had a couple of 30 ton cement mixers drive onto this hardcore and barely left a tyre mark. We’re talking solid here.
The last layer to go down was a very fine sandy layer to protect the damp proof membrane from getting punctured by stray stones, and again this got thwacked into place. So all told we have about 35 cm of thoroughly compressed stuff before we add the concrete. This slab isn’t going anywhere in a hurry.
With all that in place, time now for the damp proofing. The bright blue sheet is a very heavy duty impermeable plastic sheet, about 10 times thicker than a supermarket plastic bag, and about as manouevrable as you can imagine. With 4 of us hanging on to it and tugging it around in the stiff breeze, we managed to get it all in place and weighted down by half bricks all the way round.
John and Neil jumped into the middle of the building and laid half bricks at roughly 1 metre intervals across the base. This is to provide a support of the steel reinforcement grids that get laid on top of the bricks. This is so when the concrete is poured, we get the reinforcement “floating” in the concrete at the height the structural engineer specified in the technical diagrams. The concrete finds its own way over and around the bricks and the reinforcement bars thus providing the optimum strength slab for our house.
OK, over to the garage and repeat.
The concrete starts arriving at 8am on Monday morning (which could mean anytime between half six and eleven o’clock) but by the end of the day, we’ll have a floor.
And the next thing that happens to it is we start building walls on it, but that’s a little way away just now.