This post is in collaboration with

 

 

 

 

 

 

Finishing this section of our outdoor living space had been on our to-do list for a while, and we're so happy to now have it complete so we can enjoy long summer days here with family and friends. This entertaining area is made for these warmer months, eating, relaxing and hanging out with the ones we love.

 

Down in this sunken lounge area, we have our firepit, and when we were designing this build, we decided to add in a woodfire pizza oven here as well. Being that both the fire pit and the pizza oven uses wood, it made sense to link these together close to the wood box. For the benchtop for this pizza oven space, we went with concrete as it's durable for all seasons and is an inexpensive option for our large and custom-size build area. Aaron has worked with concrete before, but not with bespoke mouldings, so it took a little researching to figure out a game plan. It turned out to be an easy than expected project, and Aaron believes that even a novice DIY'er can achieve great results. It could be used on a much smaller scale too, like creating a coffee or side table- top also. We picked up all of the benchtop materials we needed for the benchtop from our local Bunnings and we also got the Matador pizza oven and Matador pizza spatula from there too. To see our 'how too' video on Instagram, you can view part 1 HERE and part 2 HERE.

HOW TO MAKE YOUR OWN CONCRETE BENCHTOP

Tools needed:

• Hammer, tape measure and pencil 

• Skill saw 

• Drill 

• Grinder or wire cutters 

• Trowel and/or off-cut of melamine for smoothing concrete

• Something to vibrate the concrete with - a rubber mallet or we used our massaging gun
   

Material list with cost: 
For our 3000mm x 800mm benchtop, which we made in two parts, we used...

• Melamine sheets - we used 2 sheets of 18mm, double-sided melamine particleboard in arctic white embossed, which was a ‘special order item at Bunnings. There is a range of Melamine available in store which you can shop to find the size that suits your project best or ask the team at the Customer Service desk if you’d like to place a ‘special order’.

• Maxcrete High strength concrete 20L bags - $13.25 each (we used 12 bags) 

• Reinforcing mesh 665 Handy Sheets  - $32.30 each (we used 2) 

• 100% silicon - $19.49

• Cemix concrete sealer - 4L - $80.05 

• Matador Pizza Oven - $599

• Matador pizza oven spatula - $39.99

Total cost for our benchtop and pizza oven = $1,195.13
​

Important tips before you begin 

• If your shape is not symmetrical (like our bench which had a pointed corner) your mould needs to be made in reverse, so when you flip the mould over, the benchtop is in the correct orientation.

• The bottom of your mould becomes the TOP of your bench. It gets flipped out, upside-down when de-moulding. The smooth surface of melamine is what makes the concrete smooth.

• You need to use gloss melamine sheets for your mould as this will result in a gloss finish on your concrete for a great end result.

How to make the concrete benchtop mould 

1. Cut the melamine to the size needed (see tips above) and cut the strips for the sides also. This will define the thickness of the benchtop. Screw these on. We made two moulds for the benchtop, because the bench was longer than a sheet of melamine, and also to make the weight manageable when turning the concrete out of the mould. 

2. Silicone the internal corners of the mould - this will give the benchtop a slightly rounded edge. Once the silicone is completely dry, you are ready for the concrete phase.

3. While you are waiting for the silence to dry, cut your reinforcing mesh to size to fit inside the mould, allowing an inch gap around the perimeter. You will need to have this precut, so it’s ready to go for the concrete stage. Set this aside for now

4. When you are ready to pour the concrete, make sure the mould is on a strong and flat base. We took our mould once built to the benchtop frame for pouring.

5. If you want to change the colour of the concrete for your end result, you can add pigment during the mixing step, making sure you add the exact same amount of pigment to every mix you do for a consistent result. 

How to pour the concrete 

1. Spray mould with cooking oil (we used canola) to act as a releasing agent

2. Mix MaxCrete concrete with water according to package instructions. We have a small concrete mixer, so we used this, but Aaron suggests mixing this with a spade in a wheelbarrow as an alternative. 

3. Add a layer of concrete into the mould, halfway up the sides

4. Add the reinforcing mesh, slightly pushing down on it, and then cover with more concrete.

5. Take your time to make sure the surface is even and smooth. You can use a trowel and/or a straight edge off cut of Melamine to screed off any excess concrete. 

6. Vibrate the mould to remove any air and bubbles. We used our massaging gun for this step which worked perfectly, but you can also use something like a rubber mallet to tap the mould. The more you vibrate, the better the result of the bench will be, so be sure to take your time and do this step thoroughly. 

7. Leave the concrete to cure for 3-4 days. We covered ours by draping an old sheet over (without touching it) to keep out of sunlight and stop debris from nearby trees from falling on the concrete.
    

How to de-mould and finish the concrete 

1. Unscrew the sides and remove the mould.

2. Flip the concrete benchtops and set them into place. 

3. Wet and dry sand the top and side surfaces with 1200 grit sandpaper, until you remove any imperfections, then leave to dry

4. IMPORTANT STEP - leave the concrete to cure for 28 days. This phase allows the product to gas off and for the colour to settle. Next, you want to seal the concrete with Cemix concrete sealer. This finishes the benchtop and adds a protective layer.