Preparation for Surface Perfection

Whether you want a smooth or textured finish to your concrete, you’ll need a concrete delivery float to help you complete the job. Floating will remove surface imperfections and compact the concrete in preparation for finishing. Once your concrete has been poured, levelled and tamped to remove any air bubbles, go over it with a float. This can be a small hand tool like a drably or, for large areas of concrete, a bull float (a large, metal float with a detachable handle) or power float with an engine. It’s important that you wait for any water that came to the surface of the concrete when you were tamping and levelling to soak back in completely before you begin floating. If you don’t, you will remove some of the water before it has had a chance to be re-absorbed, weakening the surface of the concrete. When you start floating, make sure you only push the bull float in one direction and keep its front edge slightly above the surface. Just do these two or three times or you will overwork the concrete which can also weaken it.

Alternatively, you can use a power float, but the concrete delivery Brisbane needs to be a bit harder in order to take the weight of the machine: it’s ready when the heel of a boot leaves only a small impression. Both hand and power floating produce a fairly flat, slightly textured surface which can contain float marks. To create a smooth, dense surface, go over it with a steel trowel once all the water has drained away and the concrete has started to harden. Do this by holding the trowel almost flat and swinging it in large circles while pressing down on the concrete. Repeat no more than two or three times. If you want to add more texture to create a non-slip surface, you can push or drag a stiff-bristled brush in one direction to create slight ridges. Once you have finished, keep the concrete damp for the next few days to allow it to set slowly. Fresh concrete delivery needs the right amount of moisture, heat and time to allow it to achieve its intended strength.

Hot sun, dry air, drying winds and frost can all affect the durability of newly-placed concrete and cause it to crack. Effective curing stops the concrete drying out too quickly as it hardens. The easiest way to do this is to keep the concrete damp by covering it with plastic sheeting. This is particularly important in temperatures over 20°C. Although it is not advisable to lay concrete in adverse weather conditions, if it is unavoidable and temperatures are likely to dip below 4°C, hessian sacking or similar can be used to insulate it and prevent the moisture inside the concrete freezing. Take care that the surface of the concrete delivery Brisbane isn’t marked by any sheeting or sacking used: plastic sheeting, for example should be mounted on a timber frame, clear of the surface. Liquid curing compounds are available as an alternative, which are sprayed on the surface of the concrete to form a semi-permeable layer.