MELBOURNE, AUSTRALIA

How to Make Concrete Benchtops

benchtops
  • Concreting

Gone are the days where concrete is only seen as a brute, rough, and raw building material option. The development of newer techniques and technology now allows us to use concrete even within our interior spaces.

Concrete benchtops are particularly popular nowadays, as they are affordable, durable, and low maintenance. They can provide a sleek and industrial look to any kitchen but can also offer a warm and welcoming feel when mixed with the right design aesthetic.

DIYing your concrete benchtop can be challenging, but it’s not impossible! Even if you’re not looking to DIY, learning how to make concrete benchtops will give you an advantage in hiring the best professional. If you’re looking to add a concrete benchtop to your home, here’s everything you need to know.

But first, why a concrete benchtop?

A concrete benchtop can be customized to fit any of your benchtop needs. Unlike natural stones which are cut from a slab, which limits customization, concrete is mixed and poured into molds so you can create a benchtop of any shape or size.

You can also choose different colors, textures, and finishes. The customization options are endless with concrete so it’s easy to match your concrete benchtop with any design style.

On top of that, concrete is affordable, durable, heat-resistant, and generally easy to maintain. Their scratch and heat resistance are great assets, especially for kitchen use. With annual resealing, a concrete countertop can easily last several decades.

What are the steps in making a concrete benchtop?

How to make concrete benchtops can be broken down into three main parts: building a mold, pouring the concrete, and finishing touches. Before starting on your project, it’s important to have your workspace prepared. Concrete cures best between 10-32 degrees Celsius, and the ideal humidity should be above 25%. Make sure to have enough space to work in and be prepared to get a bit messy!

You’ll need the following supplies, materials, and tools to get started:

  • Melanin-coated particle boards
  • 2x4 timbers
  • Screws
  • Ready-mix concrete
  • Wire mesh reinforcement
  • Silicone caulk
  • Pigment (optional)
  • Tape measure
  • Drill
  • Sandpaper
  • Table saw and sawhorses
  • Concrete vibrator
  • Trowel
  • Level
  • Speed grinder
  • Wire cutters

#1 - Making the mold

The first step is also the most tedious and important, and it requires good attention to detail. Your mold will determine all aspects of your concrete benchtop, from the size, shape, depth, and placement of elements such as where your sink and faucet will go.

To get the most accurate mold, create a template first and remember to measure everything at least three times to ensure accuracy. Once you have your template, create your mold by sawing the melanin-coated particle boards to shape. Screw the sidewalls of the mold at six-inch intervals.

You’d also want to build a support frame around the mold, as the particleboards will not be able to sustain the weight of the concrete on their own. Using the 2x4 timbers, create a frame that’s attached and propped tight against the mold.

Once you have your mold built, carefully clean it and remove all particles of sawdust or dirt on the surface. Get your silicone caulk and caulk tool to seal all the seams and corners to avoid concrete from leaking out. Let the silicone caulk dry for at least 24 hours.

#2 - Reinforcing and pouring the concrete

To prevent the concrete from cracking, a reinforcement wire mesh is required. Use a wire cutter to allow a one inch setback between the wire grid and the edges of your mold. Secure the wire into place by using screws outside your mold and wire hooks. You’ll know that you have enough ties to support the wire mesh when it hangs nicely and is not sagging at any spot.

For a DIY project, we definitely recommend using ready mix concrete rather than mixing your own for best results. Make sure that your mold and workstation is level prior to pouring out the concrete.

Pour out the concrete into the mold, tapping and vibrating the surface as you go to release air pockets to prevent cracking. For this step, a professional-grade concrete vibrator is preferably used. This can be rented from your local rental store.

After pouring, use a trowel to flatten the surface. When satisfied, cover your mold with a plastic sheet and set it aside in a warm, humid environment for about 4 days to be cured.

#3 - De-molding and finishing touches

After four days, you may now remove the mold from the concrete and let it rest and cure for another three days. The longer your concrete cures, the harder and tougher it gets. Seven days of curing provide a sweet spot where the concrete is hard enough to hold itself while still being soft enough to grind easily.

After de-molding, check for any cracks or holes. You can easily fix these by adding a slurry of a mixture of cement and water. Let these areas dry and harden, then start polishing the concrete to remove dullness.

Once you’re happy with the texture and look of your concrete, it’s time to add a sealer and wax which will bring out the natural luster of your concrete benchtop. Then you’re all set for installation!

How can I customize my concrete benchtop?

You can either add color or aggregate to make your benchtop even more unique. Aggregates are small stones that can be added to create a limitless variety of designs. Some options include colored glass or crushed stone or even your mementos such as a broken vase or any other porcelain. There are two methods of adding aggregates into your DIY benchtop:

#1 - Mixing aggregates into the concrete

This works best when using smaller decorative aggregates and wanting them to look evenly spaced. When mixed into the concrete, it’s easier to create a uniform random look.

#2 - Manually seeding or gluing the aggregate on the mold

If you have a specific look or pattern design in mind, you can glue the aggregates to the bottom of the mold so you can have complete control of where the aggregate will be. This method uses fewer aggregates and is cheaper to make. However, keep in mind that aggregates may move, shift, or get lost during casting.

How do I color my concrete benchtop?

There are three ways to color concrete benchtops using integral pigment, dye, or stain. Here is how they differ:

Integral Pigments are pigments in liquid or powder form mixed directly into the concrete before pouring. This type of coloring ensures even color within the concrete so if it ever chips or scratches, there is no visible change in color. These colors are mostly limited to earthen shades as they are made from naturally occurring minerals. Ensure that you measure the amount of color you pour into your mixture to get the exact color shade each time.

Dyes use smaller chemical particles than stains. This ensures that the dye penetrates deeper into the benchtop and creates a translucent finish. This can be mixed or layered, so the designs you can create are endless. One negative factor about dyes is that they are not UV-stable. This means that if your benchtop is made for outdoor use or gets prolonged sun exposure, the color could fade with time.

Stains use larger chemical particles than dyes. Because of this, the stain doesn’t penetrate as deep into the concrete allowing for more opaque and vibrant colors than dyes.

Application methods of both dyeing and staining are endless. You can use brush and sprays or rugs and sponges to create varying designs to customize your concrete benchtop to your liking. It is important to note that since dyes and stains are added before sealers, these colors will penetrate the concrete which means that the concrete is not as forgiving when you commit mistakes.

How much time is needed to create a concrete benchtop?

A professional would take about 10 days to create a concrete benchtop including prep time, curing, and adding the finishing touches. The actual time depends on the complexity of the project. If this is your first time learning how to make concrete benchtops, expect to set aside a few more days to create your masterpiece.

How do I maintain a concrete benchtop?

Concrete benchtops are pretty low maintenance, and reapplication of sealers can be done once every one to three years. To extend the life of your concrete benchtop, make sure to clean spills quickly, use a designated chopping board, and avoid putting hot pots and pans directly over your benchtop without potholders.

For benchtops that are used for food preparation, it’s best to reapply food-grade wax, usually beeswax, over your counter every month to prolong its life and maintain the luster.

However, keep in mind that no sealer can offer 100% protection against stains or blemishes. Concrete develops patina over time, but we dare say that it’s a charm rather than a flaw.

While going DIY can be fun and fulfilling, hiring a professional is still your best option

Making your concrete benchtop is doable, but not everyone has the time and energy to dedicate to this project. Although the steps sound simple and straightforward, a lot of skill, engineering, and experience come into play when making a concrete benchtop. It can be frustrating to put so much effort into a DIY project only to have it not quite right as far as fit or finish.

To ensure the quality and look of your concrete benchtop and to guarantee that it will last for years, speak to the team at Absolutely Flawless Floorz. We’re specialists in how to make polished concrete benchtops. For a custom, beautiful benchtop that will fit your space and budget perfectly, request a fast free quote or call us on 0450 550 649 today!