It started to rain and I had forgotten to wear my dependable site jeans. With hot weather it’s the perfect condition to start digging around at a site, but if you happen to find yourself still digging when the rains come in, you’ll be hard pressed in following your construction schedule. So at this point the columns are poured and the walls are going up, the preparations for the second floor slab should be underway.
Preparations for the second floor requires the fabrication of the beam reinforcements. This is done by the bending of reinforcement bars to the specifications of the structural designer and architect, making the frames of beams that will eventually become the beams and slab. If there ever was a job for superman this would be it.
The forms are then constructed out of marine plywood or phenolic board in the shape of the slab and beams. These forms will serve as the containers for the mixture of cement, gravel and sand until they set and retain the shape intended for them. Upon curing, the forms are then removed.
But before the concrete is poured a lot of preparation is done.
We mentioned the reinforcement bars earlier, the designers have a particular number of bars and particular size recommended for each beam which will need to be installed in a condition that will allow gravel to fit between them.
The provisions for conduits, which are pipes where the electrical wires run in will have to be put in specially if they need to go through any concrete member. The same thing goes for water pipes, mechanical ventilation ducts and provisions like nailers for stair planks.
In a two storey house the pouring of the second floor is a major achievement and gives momentum in the race to reach the roof. In multi-storey buildings after the pouring of the first suspended floor, the whole process of rebar fabrication, form construction and concrete pouring goes on until the last level is reached in what’s known as a topping off.
Below is a video of the preparations described above: