If you need to work with concrete – either as a professional or as a DIYer – you will inevitably stumble over the question of how to get concrete polished or sanded. The obvious answer is: Using a concrete sander, grinder or polisher, diamond pads or sandpaper, water and a vacuum.
However, there are different types of concrete Sanders and grinders available on the market nowadays. Each of them has its respective strengths and weaknesses and uses where it is performing particularly well. For instance, if you polish a countertop you will need another type of sander as for harsh concrete grinding. However, both tools would be sold under the same name – hand-held sander or grinder.
In this article, we aim to share with you an overview of the available concrete sanding tools, their uses and their advantages and disadvantages.
- Concrete Grinders vs Sanders vs Polishers – What Is the Difference?
- The Different Types of Concrete Sanders, Grinders and Polishers
- Uses of Concrete Sanders and Grinders
- When Do You Need a Concrete Sander or Grinder?
- How Do You Use a Hand-held Concrete Grinder or Sander?
- How Do You Use a Walk-Behind Sander or Polisher?
- Which Sander or Grinder Should You Use to Sand a Concrete Floor?
- Which Tool Can You Use to Polish a Concrete Wall?
- Which Polisher Should You Use to Polish a Concrete Floor?
- What Is the Right Tool to Sand or Polish a Concrete Countertop?
- Conclusion
Concrete Grinders vs Sanders vs Polishers – What Is the Difference?
Grinding and sanding refer to rather rough processing of a concrete surface with high abrasiveness. This step is usually followed by honing and, as the last step, polishing. Thereby, polishing implies using a very fine grit to achieve a smooth surface as a result (source).
However, the terms concrete grinder, sander and polisher are used almost interchangeably. The different manufacturers call the same kind of tool grinder as well as sander or polisher (some even combine these names) and they use these labels for hand-held as well as walk-behind tools.
When you intend to buy a sander, grinder or polisher, it is therefore important that you do not only search and select tools by the name but also pay attention to their specifications and characteristics. Thus, you will make sure that you are getting the type of concrete sander that you really need for the job.
The Different Types of Concrete Sanders, Grinders and Polishers
Advantages and Disadvantages of Different Concrete Grinders and Sanders
This table will give you an overview of the uses, pros and cons of the different types of concrete sanders, grinders or polishers.
| Hand-held Concrete Grinders / Sanders (for sanding and polishing surfaces) | Hand-held Concrete Grinders / Sanders (for harsh concrete work) | Walk-behind Concrete Polishers / Sanders | Walk-behind Concrete Grinders / Sanders for large areas | Manual Concrete Sanding | |
| Example |   |   |   |   |   |
| Characteristics and Specifications | Motor: 6A – 10A, For (semi)professional and DIY uses. | Motor: > 9 A, For (semi)professional uses | Motor: 10 – 15 A (some even 20 A), For (semi)professional and DIY uses | Motor: 15-20 A For professional uses | Special diamond sandpaper or diamond polishing pads for concrete |
| Pros | Powerful for most surface sanding and polishing jobs, usually equipped with a water hose connection for convenient wet-sanding, often with variable speed option for smootherpolishing and sanding | Powerful and therefore ideal for harsh concrete tasks, e.g. if considerable amounts of a concrete surface need to be removed, often equipped with vacuum adaptors and connectors to reduce dust production | Large discs and a handle for upright working, efficiency and convenience of operating these sanders on floors | Highly efficient and good for daily professional use, gas-operated models can be used anywhere | A comparatively cheap solution for concrete sanding and polishing, allows sanding corners and complex surfaces with high accuracy |
| Cons | Might not be powerful enough for certain challenging kinds of tasks, Cheap and low-quality models have a short | Often no variable speed option, a single-purpose tool that cannot be used for fine polishing work, for instance. | More expensive than hand-held grinders, less versatile (but highly efficient in their intended use cases) | Comparatively large and expensive | Requires manual efforts and operation, therefore, not suitable for large areas |
| Typical Uses | Sanding and polishing concrete countertops, slabs, and other concrete objects | Harsh concrete work, e.g. removing layers of cement or entire concrete surfaces. | Grinding, sanding and polishing concrete floors | Commercial grinding, sanding and polishing of large concrete surfaces and areas | Edges, curved surfaces, small areas |
| Cost | $$ | $$$ | $$$$ | $$$$$ | $ |
| Reference | Read our expert reviews and buying guide | Read our expert review | Check prices on Amazon | Check prices on Amazon | Find the equipment on Amazon |
Hand-held Concrete Grinders / Sanders
These tools – also referred to as edge grinders – are being held by the operator during the sanding process. Therefore, they are ideal for small areas, countertops or walls. However, for floors and pathways, walk-behind sanders will be the better alternative.
Concrete Sanders / Grinders for Polishing Concrete Surfaces
Countertops and slabs made of cement containing material are usually wet-sanded and polished. Hand-held concrete grinders are ideal for this job as they can be smoothly operated by moving them over the concrete surface.
These sanders or polishers are typically equipped with a variable speed option and an integrated water supply that facilitates the wet-sanding of concrete surfaces. Some even have a function for a smoother start.
Thanks to this convenience, such concrete sanders are comparatively easy and convenient to use on horizontal surfaces. However, using them on walls can be a bit more challenging.
Concrete Sanders / Grinders for Harsh Concrete Sanding
If you need to remove layers of cement-based material (e.g. mortar) or sand down a considerable part of a concrete surface, these harsh concrete sanders will help you get the job done. They are much more powerful than their abovementioned siblings and often include a vacuum connection to absorb the produced dust.
Given that these tools are used in a semi-professional or construction environment, their ergonomy and usability caters for the needs of operators who will want to work with them regularly and for several hours in a row.
Thanks to their power –usually more than 9 A – they can even be used to cut concrete if the right cutting wheel has been mounted.
Walk-behind Concrete Sanders / Polishers for Floors and Pathways
Walk-behind grinders have a handle – often an adjustable one – that allows sanding and polishing a floor standing or walking upright. Smaller ones can even be used on walls although it requires some time to familiarize yourself with controlling this process.
Apart from the different designs of the machine, with 10 – 20 A they are also more powerful than most hand-held tools. There are even gas-operated walk-behind concrete sanders available for commercial uses.
The difference between walk-behind sanders and grinders for DIY and professional uses is mainly size, power and the price of the respective machines.
Sanding Concrete by Hand (with Sandpaper or Diamond Pads)
If you want to sand concrete by hand – which can be a good answer to small or complex concrete objects – make sure you are using proper sandpaper. Regular sandpaper is usually not strong and not durable enough for use on concrete. Get diamond sandpaper or a polishing pad with the grit and size your surface requires.
Sanding by hand is done in a way similar to using a power tool (less powerful and efficient though), i.e. using different grits with ascending numbers on a moistened surface until the desired result is achieved.
Uses of Concrete Sanders and Grinders
When Do You Need a Concrete Sander or Grinder?
You will appreciate a power tool for sanding concrete for almost all kinds of cement-based surfaces. Sanding and polishing by hand using diamond sandpaper or pads may look like a budget-friendly alternative. As concrete is one of the hardest construction materials, this will only be sensible for small areas, edges or complex surfaces.
For countertops and walls, a hand-held concrete sander will be the first choice. If you need to polish or sand a floor, you will want to buy or rent a walk-behind polisher though.
How Do You Use a Hand-held Concrete Grinder or Sander?
Wherever possible, concrete is usually wet-sanded. If you are using a hand-held grinder, you might be able to connect it with a water hose. Otherwise, you should pour some water on the area that you are sanding. Some edge concrete Sanders allow you to connect a vacuum which reduces the development of dust.
Your tool will require some diamond pads or discs that are strong and durable enough to cause an abrasive effect on concrete.
Operating a sander is comparatively straightforward – switch it on and slide it over the surface until the desired result is achieved. Some experts recommend doing vertical and horizontal movements to cover any gaps that might occur due to the circular shape of the grinding pad.
Read our detailed instructions for further details and step-by-step guidance:
How Do You Use a Walk-Behind Sander or Polisher?
Thanks to its handle, you do not need to crawl on the floor when you sand it with a walk-behind concrete grinder. Just move the sander along the surface in a consistent pattern. This type of sander is often used with following a vertical and horizontal grit to ensure a consistent result.
Which Sander or Grinder Should You Use to Sand a Concrete Floor?
The best way to sand or polish concrete floors is by using a walk-behind sander. However, these tools come with different characteristics and different sizes, generally targeting DIYers, semi-professional and professional users respectively. For large surfaces and frequent uses, renting or buying a big walk-behind polisher is likely the best way to get the job done. Homeowners can use the smaller and more affordable solution – as renting is not exactly cheap, buying such a tool can be a good alternative if you stumble over a good deal.
It is also possible to sand a floor with a hand-held tool. However, this is rather inconvenient given that you would have to crawl on the floor and taking the lower efficiency of them into account. It might be sensible if you need to sand small areas only, e.g. stairs, small slabs or patios, and if you already have a hand-held concrete grinder at hand.
Which Tool Can You Use to Polish a Concrete Wall?
The challenge of sanding concrete walls is that you will need to operate the sander on a vertical surface (sanding a concrete ceiling is even more challenging). You will have to hold and press the sander in a horizontal way which can cause quick fatigue and makes it harder to keep the area wet. An integrated water supply is not as effective as on horizontal surfaces due to the downward direction of the water flow.
Make sure you use a rather light-weight hand-held grinder with an ergonomic grip that you can operate in this position for some time. Ideally one with a vacuum connection to limit the dust production. When sanding a wall, add water frequently to keep the surface as wet as possible.
Which Polisher Should You Use to Polish a Concrete Floor?
Polishing usually implies the use of high-grit, i.e. very fine abrasive equipment, so you will need to buy the right pads or discs if you want to achieve a polished concrete surface. Mount them on your sander and follow the movements explained in the previous section. Ideally, you will be using a walk-behind concrete polisher which can be operated by standing or walking upright. Make sure you follow consistently a certain grit, e.g. horizontal and vertical movements, when you polish the floor.
What Is the Right Tool to Sand or Polish a Concrete Countertop?
For concrete countertops in a kitchen or workshop, but also for concrete tables or small slabs, a hand-held concrete grinder offers the most effective and convenient way of getting the job done. If you need to buy a concrete sander, make sure you get one with an integrated water supply (you will need to connect a water hose to get it running). This will help you maintain a constant water flow and therefore an ideal degree of moisture on the surface you are going to sand or polish. A variable-speed function will further improve the usability and allow you to adjust the operating speed to the requirements of your concrete surface.
If you are sanding concrete countertops regularly, you should buy one of the high-quality brand concrete sanders. If you are doing this once in a while only, a mid-range tool might be good enough to meet your needs. In any case, stay away from cheap low-quality offers and also withstand the idea of using a regular palm or orbital sander on concrete. Both options may look like a budget-friendly alternative, however, those tools are often not strong nor durable enough to produce good results on concrete, and some might even break down midways. If you consider buying a hand-held concrete grinder, make sure you read expert opinions but also customer reviews, e.g. on Amazon.
Conclusion
We have discussed the different types of hand-held and walk-behind grinders in this article. All of them come with their own advantages and disadvantages. If you intend to buy or rent a sander, make sure you are aware of the exact requirements of the job, get the right material and do not forget to wear goggles / safety glasses and a respirator to avoid injuries and health risks from concrete splinters and dust.
If you consider buying a concrete sander, make sure you read our expert reviews and our buyer’s guide first: