There are three different types of aggregate/stone exposure to choose from. Nil Exposure, Minimal/Random Exposure and Full Exposure. Scroll down below to get a better understanding of each exposure finish.
Levels Of Aggregate/Stone Exposure
What Is Your Favourite Level Of Aggregate/Stone Exposure?
Every concrete mix has aggregate (stones) as a component – the colour, density, size and distribution of these stones will depend on where the concrete came from, if it was specially ordered and how well it was poured and installed for polished concrete.
This form of polished concrete is high in demand and is a finish which is also the hardest to achieve. Generally, we are only able to offer this service for newly poured concrete slabs that have been poured with a high MPa number, a leveled floor and properly power trowelled floor with the helicopter-like tool. If the concrete is soft and is not level then Nil Exposure polished concrete may not be an achievable finish, the alternative would be minimal exposure polished concrete. If your concrete has not been poured yet and you desire the Nil Exposure polished concrete floor then look to get an experienced concreting company and you must let the concreting contractors know that you want the slab poured for polished concrete purposes. The main idea of a Nil Exposure is that we grind off the least amount of concrete possible so that there is little or no aggregate/stones showing in the concrete surface. If we need to, we undergo a grouting process to fill in pinholes and fine cracks in the best possible condition. Once grouting is complete, we then refine the floor with polishing pads until we reach the level of sheen you desire.
Minimal Exposure Polished Concrete has 2 types of finishes. One is referred to as the Salt & Pepper Look and the other is known as the Hit & Miss Finish. In this minimal exposure process, we grind the top layer off the surface throughout the entire floor. For the Salt & Pepper we usually grind 1-2mm and for the Hit & Miss Finish we usually grind anywhere from 1-3mm. The whole idea of this service is that you get the best of both worlds, which is a bit of aggregate and a bit of cement. Usually our clients best describe the unique feature as a floor that has character. We offer this service in both Mechanically Polished Concrete (MPC) and Grind & Seal.
Full Exposure polished concrete is the fan favourite. This popular polished concrete choice is for the aggregate/stone lovers. In this grinding and polishing procedure, we try to show as much aggregate/stone as possible throughout the entire floor. We aim to achieve full exposure provided the concrete has been poured with the right specifications and has an evenly distributed amount of aggregate/stones. To achieve this full exposure finish we have to grind extra which involves more labour and is costlier for the client than the nil or minimal exposure service. In the grinding stage we grind anywhere from 4-5mm depending on the density of the slab. We usually cannot grind any further because it can cause complications to the end result. We offer the full exposure finish in both the Mechanically Polished Concrete (MPC) and the Grind & Seal service.