If you are working on a new construction or a massive renovation, you know you need to map out a schedule in order to keep productivity maximized, meet deadlines, and stay within budget. If part of this project involves pouring new concrete and getting a smooth finish, you may be concerned about whether or not fresh concrete can be polished or if attempting to do so will cause serious damage to the freshly laid slab. To help you, we’re breaking down what you need to do to get the concrete ready to polish as soon as possible while still getting the excellent results your customers are looking for.
How Long Does it Take Concrete to Cure
Technically, most commercial concrete is strong enough to be polished just three days after pouring. However, that doesn’t mean you should jump the gun and do it that soon. Part of the polishing process is using a densifier to make sure the slab is hard and dense enough for the grinding and polishing process. The manufacturer of the densifier must approve any work that occurs within the first 28 days to see how the chemical will react and perform with the concrete. The closer to 28 days you wait, the more likely you are to get the better outcome.
Preparing Fresh Concrete to Be Polished
When you are ready to polish a new slab of concrete, you’ll want to check your concrete first to determine how hard or soft it is. If it’s a softer concrete that scratches easily when you run a key or a nail over it, you’ll want to choose a harder bond tooling, and if it’s a harder concrete, you can start with a soft bond. Because the concrete is new and should be free of blemishes, you may be able to start with an 80-grit diamond pad, but it may be necessary to start at a more abrasive pad.
After two to three passes, you can apply your first coat of densifier, then move to a finer grit, such as a 150-grit pad, then a 300-grit.
Using a Densifier on New Concrete
After grinding it smooth, you’ll want to apply a densifier to the slab. A concrete densifier is a liquid chemical that is used to turn a soft, easily scratched slab into one that is much more wear resistant and easy to grind. When applied to concrete, it soaks into the pores and reacts with the calcium hydroxide within the slab, creating a stronger, more tightly bonded crystalline structure.
After it is applied and soaks in, the surface density is increased and the porosity is reduced. The end result is a concrete that is more resistant to stains, cracks, and abrasion. While you’ve probably applied it after the initial grinding, it’s also a good idea to add a second coating of densifier as you move to finer grit polishing to fill in any small cracks and scuffs.
Contact Us for Concrete Polishing Supplies
If you want to get the best results from your polished concrete, we can help! We carry a variety of concrete tooling and concrete densifier to help our clients improve the results of their concrete polishing projects. To learn more or to place an order, speak to a member of our team today by calling (815) 472-9744 or filling out a contact form to get started!