How to build a pizza oven base?

[becxy05]

 

We have a pizza oven that we bought from Bunnings years ago, but it stands on metal legs. We want to change the base so we can store wood for both our pizza oven and fire pit in. We have decided to build it from Besser blocks and our going with an easy structure, similar to a horse shoe (but with square corners). Our biggest problem is trying to build the top so the pizza oven can be placed on top. We are looking for something premade that can be bought from Bunnings. Research has shown us Hebel sheets, but I’m a bit worried that won’t work and hold the weight of the oven. Our dimensions are 1m x 1m. Is there other suggestions? How difficult is it to build a concrete top? Not our photo, but an example of the shape we think we will use. 
Thanks, Bec 

[Remarka6le]

Hey @becxy05 ! Concrete tops are easier to build than one would think (though having a concreter for a Brother in Law sure helped in that department). Grab yourself the following: 

• Melamine board for the base
• Excess Melamine cut to size for the edges
• Rubbing Alcohol (to clean the base and sides)
• Caulk
• Metal reinforcement (this can change based on size and density of your top)
• Concrete
• finishing trowel
• Wet Sanding kit
• 2x4 piece of wood
• Sealer

Start by cutting your Melamine board to size, once this is done, cut some melamine sides and screw them into the base and the sides. Take out your rubbing alcohol and clean the entire interior, once finished, caulk every joint and seam inside of it and then scrape off the excess with an old card (like a credit card or drivers license). 

Mix & fill the bottom with concrete so it's about half full to the top, then add your metal reinforcement, followed by more concrete to fill to the top. Once done, grab the 2x4 and shimmy it along the top to get rid of excess concrete, if any gaps appear, just use the excess to fill it in. Keep doing this until you have no more excess coming off. 

Next step is to vibrate your mold to get the air bubbles out, I use a massage gun and just go around the edges and underneath the mold (if you have it on horse legs), though shaking the mold steadily from side to side works as well. As water rises to the top, use your finishing trowel to glide over the excess water coming up to create a smooth surface and to remove excess water. This can take a while, but be consistent and you'll get a smooth surface. 

Leave it to dry for 3 days before removing the mold, though I left mine for a month to fully cure. Wet sand the bottom & top, then seal each side. Top done!

[becxy05]

Thank you so much! We will give that a go! 

[EricL]

Hello @becxy05

It's great that you've received a detailed recommendation from @Remarka6le. Just to add to the suggestions made, I recommend putting in some Whites 1800 x 1050 x 5mm Light Duty Reo Mesh or similar. This will allow the slab to take some weight and should it crack will hold the slab together. Make sure to put in some Whites 25 - 40mm Plastic Reinforcing Bar Chair to prevent the reo mesh from sinking to the bottom of your assembly.

The magic ingredient before you start putting in the concrete is WD40. Spray it on all the surfaces the concrete will be touching. When the concrete dries, frame disassembly will be easier.

Please keep us updated with your progress, we look forward to seeing your oven base assembled. 

Eric

[becxy05]

Thank you,

Super helpful! Just a few questions- the WD40, is that instead of chaulking? Or it the chaulk more of a sealer to prevent leakage? 

I was kind of hoping to make the top in place, so I’m a bit worried about the melamine board. Is there something else I could use or do I just accept that the base will become part of the concrete top? 

I will definitely upload some images once we are done.

thanks! 

[Brad]

If building the top in place I would cut the base board to fit the gap and that would give one edge to start attaching the sides.

You will need some bracing under the base board to take the weight of the concrete while it dries and it will need to be easy to remove once the concrete has dried so you can remove the base board.

You will need some bracing for the sides and your caulking needs to be spot on to avoid runs onto the bricks.

WD40 is the release agent and the caulk prevents leakage.

If I was building it off the base I would put in some threaded anchors so I could use some eye bolts to lift it with the neighbours engine crane or if I could slide the slab off the base board I could use my lifting table ( lifting table is a more safe way to go but they are not common )

[EricL]

Hello @becxy05

@Brad's explanation of the caulk and WD40 is spot on. Just keep in mind how you form the inside of the frame will be the final shape of the outside of the oven base.

If you need further assistance, please let us know.

Eric