Plan around the forecast, not the calendar
We read the three day forecast every afternoon and book mixer trucks for the next dry window. Big slabs go on the programme with a backup date two days later, agreed with the client and the batching plant in advance.
Night pours help twice: fewer storms at night in most of the season, and clear roads for the trucks.
Cover before you need to
Every pour has rolls of heavy polythene and timber battens on the slab before the first truck arrives. If rain starts, the crew covers the finished area first and stops at a planned construction joint.
- Joints are marked on the drawings before the pour, not decided in the rain.
- A tarpaulin canopy goes over the pump line and the vibrators.
- Fresh concrete is never finished with rain water on the surface.
Protect the cure
Rain does not harm concrete that has set, and the humidity helps curing. The danger is the first two to four hours. After that we keep slabs covered and wet for seven days, rain or sun.
Drain the site first
Most lost days in the rains are not about the pour at all. They are about a flooded basement, a bogged down truck or a site road turned to mud. Our sites get temporary drains, laterite roads and a pump with its own generator before the first heavy rain.
