What is concrete formwork?
Formwork is the common terms used for temporary or sometimes fixed moulds that hold concrete into place when being poured. Any shape or object can be formed up and cast in concrete when used with steel reinforcing.
What does formwork have to do with polished concrete?
It simply needs to be done well. Well placed and braced formwork will result in well placed and formed concrete. Well built formwork will allow you to vibrate the concrete into place eliminating air pockets that leave behind holes that require patching. Good formwork will also hold its shape when the heavy concrete is dropped in. Don’t underestimate the pressure of concrete, at 2.5 tonnes a cubic meter formwork can be pushed and lifted out of the way if not pinned down properly. The grinding and polishing process will therefore be much easier seeing as is is already a tough job. Patching defects and grinding out humps and bumps will never create the perfect look, they will always be seen. Too many jobs we arrive at are left in an unfinished state, the attitude that the concrete is going to be grinded so who cares what is looks like is totally wrong practice. Proper 32mpa concrete is extremely hard, to take out a hump can take a whole day even when using grinding lubricants.
So if you are forming and pouring concrete for a polished concrete look, the finish on the concrete needs to be better than if you were laying carpet or tiles over it. Only use an experienced concreting contractor that is familiar with polished concrete and what is needed for a good job.