Looking for advice on stand/hearth

[tonester.j]

Hello,

I'm Tony, I found this forum researching cooking surfaces, after almost getting conned by the vermiculite youtubers..... This forum is amazing, so much information to consume!

I'm looking at doing a 75cm, 2" homebrew cast, with 40mm ceramic fibre blanket, 2" Perlite insulation, with a stucco shell, on a 3" reinforced hearth. Bottom insulation will be 100mm perlite 5:1, I haven't found surface bricks yet but looking for something around 40-50mm deep.

I have an old (35 years) brick grill stand that I was hoping to "extend" to become the hearth stand. It's 108cm wide which is pretty much perfect, but it needs more depth.
I'm a bit tight on finances and time, so I was hoping to get away with re-using this. I know it's better to over-build this, I get it, and I would love to do it.... but it turns into a much bigger project.

Anyway, here are some photos of the grill stand, and a template showing the brickwork. The red bricks are the existing structure, and the yellow are the new bricks. The 2 yellow bricks at the front are above existing structure, 3 bricks high...

So my question (or three) is.... is this thing going to hold up? Am I crazy? Or should I just knock it all down and build something stronger?

Thank you

[Neil.B]

Some builders have built on flimsy looking metal or wood legs, so this should be ok. As long as all sides are built up equal and the structure is solid, the hearth should distribute the weight.
Do you have the room to build next to it and use it as a kitchen?

[JRPizza]

Tony I'm confused looking at your sketch. It appears the red existing bricks are at the opening end of your oven and the new yellow ones at the back. Were you going to tear out the bushes and build the oven facing away from the front in your pics, or am I seeing things wrong (I am slightly color blind )?
Edit - Nevermind, I figured it out. You are going to just build back a little so that the existing front of the stand remains the front. Sometimes I'm slow

[tonester.j]

Thanks Neil & JR,

I have a little less to worry about now.... after seeing all the huge cinder block bases on the forums I was worried it wouldn't be strong enough.

JRPizza yep, that's it, just extending the back, and bringing the two front edges up to level... I'm going to have fun with that tree behind it... not sure how I'm going to get it out to make the foundation. It's about 10 inches diameter, it's just been pruned low which is why it's so bushy. There's a pool fence directly behind the tree so I can't just rip it out with the tractor. Maybe some fire will do the trick.

Neil.B Yes I have room on the right, although I would have to rip out more garden... I might keep that in mind for a stage 2 project, as time and cash are a bit limited at the moment. If I can score some free bricks from somewhere I might be able to pull it off.

[Neil.B]

Thanks Neil & JR,

Neil.B Yes I have room on the right, although I would have to rip out more garden... I might keep that in mind for a stage 2 project, as time and cash are a bit limited at the moment. If I can score some free bricks from somewhere I might be able to pull it off.

All of my base was free bricks/blocks as well as the insulating blocks, so it can be done.

[MarkJerling]

Hello,

I'm Tony, I found this forum researching cooking surfaces, after almost getting conned by the vermiculite youtubers..... This forum is amazing, so much information to consume!

I'm looking at doing a 75cm, 2" homebrew cast, with 40mm ceramic fibre blanket, 2" Perlite insulation, with a stucco shell, on a 3" reinforced hearth. Bottom insulation will be 100mm perlite 5:1, I haven't found surface bricks yet but looking for something around 40-50mm deep.

I have an old (35 years) brick grill stand that I was hoping to "extend" to become the hearth stand. It's 108cm wide which is pretty much perfect, but it needs more depth.
I'm a bit tight on finances and time, so I was hoping to get away with re-using this. I know it's better to over-build this, I get it, and I would love to do it.... but it turns into a much bigger project.

Anyway, here are some photos of the grill stand, and a template showing the brickwork. The red bricks are the existing structure, and the yellow are the new bricks. The 2 yellow bricks at the front are above existing structure, 3 bricks high...

So my question (or three) is.... is this thing going to hold up? Am I crazy? Or should I just knock it all down and build something stronger?

Thank you

I imagine it can work, assuming there's some sort of foundation under the existing BBQ bricks. What you want to avoid is having the new construction settle more or less or differently to the existing construction. If that happens, you'll soon have an oven on a tilt like the leaning tower of Pisa and that won't be a very good outcome!

So, I would, if I was you, make sure you have a good foundation front and back and tie the existing brickwork to the new with some drilled in epoxy set steel threaded rod ties.

[tonester.j]

I imagine it can work, assuming there's some sort of foundation under the existing BBQ bricks. What you want to avoid is having the new construction settle more or less or differently to the existing construction. If that happens, you'll soon have an oven on a tilt like the leaning tower of Pisa and that won't be a very good outcome!

So, I would, if I was you, make sure you have a good foundation front and back and tie the existing brickwork to the new with some drilled in epoxy set steel threaded rod ties.

Thanks Mark, yes I'm worried about what's under that structure.... it's on the edge of some brickwork surrounding a pool. I'm going to dig around the back of it soon, so I will find out if it's on a slab. If not I guess I'll have to knock it down, or build next to it.

Do you think a 3" thick hearth is ok for a 30" homebrew cast? I see 4" is usually the recommended thickness, but was hoping to get away with 3 considering it's a smallish cast oven.

[MarkJerling]

Thanks Mark, yes I'm worried about what's under that structure.... it's on the edge of some brickwork surrounding a pool. I'm going to dig around the back of it soon, so I will find out if it's on a slab. If not I guess I'll have to knock it down, or build next to it.

Do you think a 3" thick hearth is ok for a 30" homebrew cast? I see 4" is usually the recommended thickness, but was hoping to get away with 3 considering it's a smallish cast oven.

What's your biggest span? And what sort of steel are you sticking in it? It could work with 3" (depending on the steel) but I'd go 4". (But of course, I over-engineer everything!) LOL

[tonester.j]

I've got a heap of old half inch rebar lying around, was just going to use that. Biggest span is about 1040mm at the front where there isn't much weight, just under the arch entrance. (see diagram in 1st post)
I suppose I was just worried about the weight of a 4inch slab on those bricks...

[MarkJerling]

I've got a heap of old half inch rebar lying around, was just going to use that. Biggest span is about 1040mm at the front where there isn't much weight, just under the arch entrance. (see diagram in 1st post)
I suppose I was just worried about the weight of a 4inch slab on those bricks...

The bricks will cope with the extra inch. A 3" slab can work with decent rebar like that, but bear in mind that there won't be much concrete cover over the steel so, with time, moisture ingress etc. I'd play it safe and go 4". Of course, mine's completely over engineered at 6"!