Concrete Surface Preparation: An Overview
Are you a contractor looking to diversify into other service offerings? Concrete maintenance and restoration; including cleaning, prepping, polishing and staining, might be what you're looking for.
Nothing can last forever. That includes what might be thought of as bulletproof, concrete floors. Even concrete floors will wear, crack, and especially, stain. Fortunately, you can fix almost any surface, and concrete is no exception. It starts with a process simply called “surface preparation.”
What is surface preparation?
When we talk about surface or floor preparation, we’re referring to the act of removing oil build-up, thinset or mastic, old floor material, acid-based stains or other contaminants, and then prepping the surface for a new coating, polishing, or new type of flooring. Surface preparation fulfills two distinct functions: first, you are scraping away or grinding off the old stuff, and second, proper preparation will ensure the surface is ready for a new “surface profile.”
How do I prepare a concrete floor?
There is a wide range of methods used to prepare a floor or surface, but of all the options, the most common are lumped into two categories: chemical and mechanical.
What do I need for surface preparation?
Chemicals are often used to remove thinset or mastic from concrete surfaces. Aramsco carries a wide range of mastic removers. After using a mastic remover, which is often solvent based, you'll need to remove the mastic remover that is left behind. A good detergent-based wash on the alkaline side (pH above 7) will get rid of any remaining solvent residue. The next chemical used depends on what you're trying to accomplish, but if you need to prep the surface to lay down an adhesive, it's common to use an acid cleaner to etch the surface.
Mechanical floor prep offers a variety of options, but you’ll have to determine what’s best depending on the area size, surface material, and use. If you’re unsure which piece of equipment is right for your job, here are some ways to do it:
- Abrasive air blast: This system uses compressed air combined with a variety of softer material to blast and clean surfaces.
- Shot blasting: A shot blaster utilizes a high RPM wheel to blast steel shot into a concentrated area. The shot, however, is highly controlled and immediately captured for reuse.
- Scarify/milling: Scarifying machines pummel concrete with jagged cutting wheels. It’s a powerfully aggressive method, generally used to remove thick concrete quickly. Milling is similar to scarifying but on a grander scale. A milling machine will often use multiple scarifying heads.
- Grinding: These machines include handheld models for smaller jobs, edges or stairs.
- Scrapers: These machines scrape off unwanted material from the floors. If you need to cover a large area, consider using a ride-on scraper.
Why do I need to prepare my floor before finishing it?
Safety is paramount. And unwanted contaminants can interfere with a surface’s adhesion. In essence, you want to remove loose particles and pieces of floor that prevent bonding, which can lead to trips, falls, slips and stumbles.
Furthermore, a well-prepared floor is aesthetically pleasing. Proper preparation results in glossy, polished surfaces that look nice and feel smooth and comfortable to walk or drive on.
Does it matter when we prepare a surface?
Be mindful of weather and humidity. Moisture can influence the efficacy of the job, particularly on outdoor surfaces.
What is happening to the floor?
Scarifying, milling or grinding equipment, as well as acid etching, cut small grooves in the subsurface. These grooves resemble minuscule peaks and valleys that help the top layer grip the foundation. Remember, if the top layer is laid too deep into the valleys, the peaks will protrude through the surface. A general rule of thumb calls for a third of the floor material to be above the “peaks.”