How To Sand Concrete? (A Step By Step Guide)

Nowadays, it is a trend to have sanded concrete in our homes and offices because of the classy and professional look it creates. But it is a bit tricky to sand concrete. So you must have proper knowledge on how to sand concrete to bring a grandeur appearance.

Concrete is basically a flooring material used to build the foundation of buildings for its high durability. And sanding is essential for resurfacing treated concrete floors. Today homeowners opt for sanded concrete to add luxury to their floors.

Why should you sand concrete?

These days, people prefer the sanded concrete floors as they offer some outstanding features; some of them are as follows.

Outlook of surface

You can achieve an aesthetic look around your house by sanding the concrete surfaces. This is applicable for concrete floors, walls, concrete furniture, kitchen countertops, and other visible objects in our house.

Remove stain or paint

When you cannot remove paints, stains, or glue from concrete surfaces in any way, in that situation, sanding is the best solution. It will help restore the original look of the concrete surface.


If concrete around your home becomes cracked, damaged, or chipped, then the first thing you have to do is sanding. But the color of the filler may vary a bit from the actual color of concrete. In this case, you might apply a stain after sanding.

Remove sharp edges

While building concrete floors, sharp edges and corners may occur even if you pour concrete thoroughly. These faults may cause accidents as you can touch them unconsciously. Therefore, you need to remove these imperfections to avoid such unwanted circumstances. Besides, these uneven and rough textures can cause abrasion and increased wear and tear to tires if you have concrete driveways. A sanded floor levels the joint and enhances the overall look of that surface.

Types of concrete finish

Concrete is a well-known and versatile construction material used worldwide for all types of construction purposes. Concrete can be molded into any size or shape in its green form. And it can give different finishes with the help of various finishing techniques and tools for a beautiful and durable surface with a higher aesthetic value. However, through the sanding process, you can achieve three types of concrete finishes.

Smooth finish

The most uncomplicated finish you can achieve through sanding concrete by hand or with the orbital sander is the smooth finish. It requires not removing any concrete but polishing the top layer for a shiny and smooth surface. This is suitable for countertop or similar surfaces.

Salt and pepper finish

This is the intermediate finish where approximately 1/16th of an inch from the top layer is sanded off. So it creates an attractive and speckled finish. With this finish, the sand underlying the top layer is exposed without revealing any aggregate. Thus, a polished granite-like outlook is achieved at a meager cost.

Exposed aggregate finish

This finish requires removing lots of material as it reveals the aggregates that you mixed into concrete. It is not possible to achieve without a powered sander. The aggregates can be seashells, attractive stones, granite, colored glass, and other strong materials. And the result of this finish is a safe and nonslip surface which is great for porch and sidewalk.

To achieve this finish, you have to pour, level, and trowel the concrete. Then to slow down the hardening of the surface cement, you have to treat it overnight with a chemical. After that, wash the surface with water to remove the top layer and reveal the aggregates.

What is the best tool for concrete sanding?

Though concrete is very hard, you can sand concrete floor but with proper equipment. To sand a spacious space, you should go for an orbital sander. To be more specific, a random orbital sander is ideal for this purpose. This handheld random orbital sander has already proved itself as a powerful sanding machine.

What is a random orbital sander?

Random orbital sander is a power tool designed for sanding in which the blade gives a random orbit action. In this sander, the rotation angle of the disc and the head is variable. However, it combines the aggressiveness and speed of a belt sander with the ability to generate a finer finish than that from a slow-speed orbital sander.

Moreover, you will not get swirl marks while using this tool because of its random sanding action. Besides, the random orbital sander features an integrated dust collector to save you from the metal debris. There are many reasons like these behind choosing this tool for sanding concrete. Some of them are as follows.

  • You do not need to give hard labor.
  • It can work great in hard materials like concrete.
  • You will get a smooth and consistent surface.

What do you use to sand concrete?

  • Floor grinder (We recommend avoiding wet models)
  • Diamond grinding pads
  • Epoxy resin
  • Vacuum (attach with sander)
  • Squeeze or sponge mop
  • Plastic sheeting
  • Duct tape

Necessary PPEs

  • Hand gloves
  • Goggles
  • Face mask
  • Earplugs

Sanding concrete (A step by step guide)

  1. Clear the concrete floor you are going to sand. Remove all the furniture and other objects.
  2. Use plastic sheets to cover the walls, vents, doorways, and other surfaces. In this way, you can protect your walls from dust and debris.
  3. To get rid of dust and debris, mop down the floor and let it dry.
  4. Using duct tape divide the floor into sectors or zones. It will help you to focus on one sector at a time.
  5. Now start sanding with 30 to 60 grit sandpaper. However, we recommend starting from a corner side and move up the floor. Because starting from a corner will enable you to maintain a proper order of sanding each sector of the floor.
  6. Now make extra vertical passes as it helps cover narrow passes too. Each time this method should cover half of the previous pass.
  7. Remain extra careful while sanding bumps. Sand thoroughly until you get a smooth surface. Try few passes. Make sure not to leave the sander stationary; otherwise, there will not be even finishing.
  8. Now apply epoxy resin to fill any sort of cracks or divots. Let it dry to settle before taking the next move.
  9. Now restart from the corner where you completed the first set of passes. Finally, reverse the process to complete at the first corner you started.
  10. This time make another two sets of passes, sanding horizontally in two direction.
  11. Now clean the concrete floor with a damp rag or vacuum. Then apply an even coat with concrete sealer. Do not forget to follow the instructions to let the sealer do its task.
  12. After that, migrate to an 80 to 120 grit sandpaper to get a more smooth result. And repeat the steps from 6 to 10.
  13. Again clean the floor with a damp rag or vacuum and migrate to finer grit papers like 240 or 320.
  14. Continue repeating the steps from 6 to 10 with gradually finer grit papers until reaching the industrial ideal 1500 grit or more. Then, as usual, to get rid of dust or debris, continue mopping from time to time.
  15. Re-examine the floor for better results. If you get any irregularities or traces of stains or paints, mop the floor for one last time.
  16. At last, if you feel it necessary, then you can paint on the floor as the final step.

How to achieve a uniform look on floors?

We have learned about sanding concrete floors. But while sanding the interior concrete floor, we recommend applying the same process on the whole floor surface, whether necessary or not. Because sanding affects how far colors and stains can penetrate the surface. So stain the entire floor if you sand only one particular portion to avoid different shades on the floor.

Maintenance of sanded concrete floors

You will have to follow the below rules to maintain your sanded concrete floor.

  • Clean the floor daily with a microfiber pad to keep the potentially damaging dirt particles off the floor. Maybe you do not know that soil acts as an abrasive and is responsible for ruining the shiny effects of polished concrete.
  • Always use a clean mop and clean water for wet mopping of the floor. For cleaning large footage areas, use automatic floor scrubbers equipped with nonabrasive pads.
  • While wet mopping, use a neutral floor cleaner with water to suspend the dirt particles. If you only use water, it will leave maximum dirt on the floor. It results in rubbing the floor and discoloring the floor surface.
  • If accidentally water, tea, coffee, or soft drinks spill on the floor, clean as early as possible. Otherwise, the floor surface will absorb them and leave strong stains.
  • Whatever cleaner you use, give that sufficient time to break down the grime, like grease or other contaminants, and after that suspend the particles. If you immediately mop the floor after applying the cleaning agent, it will not get enough time to work.
  • The cleaning solution should not dry on the floor.

Safety tips

  • As breathing in concrete particles is harmful, keep a bucket of water near you to mop down frequently. It will prevent the debris from spreading too much throughout the air. While working indoors, keep the windows open for ventilation of the room.
  • Wear a mask and goggles.
  • Keep your child away from the working area.

Concrete sanding FAQs

1. Can you sand concrete with regular sandpaper?

Yes. But it is definitely not the best option as regular sandpapers wear down very quickly. Moreover, it is a very time-consuming and laborious process. Additionally, you will need a lot of sandpapers for this task. So the best choice we recommend is the special diamond disc or a floor grinder.

Diamond sandpapers are famous for their long-lasting feature. Moreover, it saves a lot of time. Though it is a little expensive, it is worth buying to relieve you from hard work.

2. How to sand concrete if it is stained?

If the concrete is stained, clean it down before sanding and hope stains come out. Removing grease is essential as it can affect the pigmentation process and stop stains from penetrating fully into the concrete surface.

You can clean the concrete surface with a mixture of 1 cup of TSP (trisodium phosphate) or two tablespoons of degreasing dish fluid with water of 4 gallons. Mix these well, and with a stiff brush, scrub the whole surface.

After cleaning, rinse down the surface, mop it and then let it dry.

3. Why should you apply a concrete sealer?

As concrete is a porous element, it quickly absorbs liquid. In a freeze-thaw environment, the spread of frozen liquids can destroy the unsealed concrete surface. That is why applying concrete sealer is essential. Moreover, fertilizer, oil, salt can damage and discolor unsealed concrete.

4. How do you sand a concrete floor by hand?

Though sanding concrete floors is a tricky task, you can do it by hand. For this, you need to use diamond pads or sandpapers. However, sandpapers are comparatively expensive, but their performance worth it.

5. Which tools can you use to sand concrete?

There are two types of tools for sanding concrete: handheld concrete sander/ grinder and walk-behind sanders.

The handheld option is suitable for DIYers. You can use handheld sanders for almost all types of surfaces, including walls or even ceilings.

There are some handheld grinders suitable for harsh concrete works. They are more powerful, and rather than smoothening or polishing surfaces; they remove concrete layers.

On the other hand, walk-behind sanders are perfect for large concrete surfaces. These are expensive tools. So, DIYers can use these on a rental basis.

Final Words

Hopefully, you have understood how to sand concrete to achieve a perfect look in your house. In the modern age, it has become the need of every homeowner because of the fancy look it creates. And the most important thing is you can do it by yourself.

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