Concrete polishing is one of the most popular construction materials in the world. It’s incredibly strong, durable, and can be formed into just about any shape imaginable, making it extremely versatile for almost any construction application.
Almost every construction project involves concrete flatwork, whether it’s for a sidewalk, a driveway, or the foundation itself, so it’s important to know how to do it right.
To help you out, we’ve put together a quick list of tips so you can execute the concrete flatwork for your building project to perfection.
- Prepare the surface for concrete
Concrete makes for a solid foundation for any building, but even concrete needs to have a solid foundation. That doesn’t mean you need to pour twice the concrete though.
Before you get started, you should remove all vegetation from the surface of the ground, as well as any roots. The ground needs to be solid and flat so that the concrete will pour evenly, and be supported equally from underneath.
A good base is invaluable when it comes to pouring concrete. If there are holes, roots, or loose materials underneath, you can risk cracking and crumbling when your concrete finally dries.
You can ensure a solid base for your concrete by clearing the location and pouring compact-able base materials over the ground’s surface.
The necessary depth of your base will vary depending on the climate of your area and how much weight your concrete flatwork needs to support.
- Make sure there aren’t any bubbles
When putting in concrete flatwork, you want to ensure that there aren’t any bubbles or voids in both the ground beneath and the concrete itself.
Voids in the base can become dangerous, as the concrete slab won’t be fully supported. You run the risk of it shifting once it’s dried, putting you and others at risk.
Bubbles in the concrete itself can also cause cracking once dried, so make sure your concrete mixture is consistent and not too dry.
To help get rid of any voids in the concrete, tap the sides of the form with a hammer. This will help the concrete settle into any remaining holes in the base, as well as up against the sides of the form itself.
- Add your finish texture, but not while its bleeding
After concrete begins to set, you might notice water rising to the surface. This is called bleeding.
Make sure you don’t add concrete powder to absorb excess moisture from the surface, as it will make the surface crumbly and uneven.
You can avoid “bird baths,” on the surface of the concrete by preparing the base properly before pouring.
- Install contraction or expansion joints
Concrete expands and contracts with fluctuations in temperature. If the concrete doesn’t have contraction joints installed on the surface, it will crack when it contracts.
Similarly, expansion joints leave space between slabs of concrete to avoid cracking when the slabs expand.
Contraction joints often serve as both contraction and expansion joints because most times, once the concrete has contracted, there’s enough space left between each slab to allow for it to expand without cracking.
To install contraction joints, all you need is a grooving tool. You could wait until the concrete dries and then use a saw to cut joints later, but using a grooving tool while the concrete is still wet is easy and will save time down the road.
It’s important to get the right depth for the contraction joints. They should go a quarter of the way through the concrete. For example, a 6-inch concrete slab should have expansion joints approximately 1.5 inches deep.
- Finish off the edges
To avoid sharp, uneven edges from forming when your concrete is dry, finish them off with an edging tool. This will give your concrete flatwork a polished and professional look, and will help prevent brittle corners from cracking.
Conclusion
There’s more to concrete flatwork than mixing and pouring, but if you follow these tips, your next building project may just be the best one yet. For more information on concrete flatwork, and more, head over to FMP Construction to have your questions answered.
