39 inch Pompeii in Lincolnshire England

[andis]

Like most people I have been hanging around for a while and gathering information.

I have now been handed the perfect excuse to build a WFO
I bought a house with a retaining wall that the previous owner had part built and intended to finish with a set of steps to the rear of the property.
But I had a better idea and convinced the other other half that it would be a cheaper option to build an oven in the wall.

I put in a foundation and built a corbeled stand before the winter drove me inside. Now spring is here I have poured the base and started planning a layout. The 39 is a compromise between 36 and 42.

The oven will be enclosed in a house with a roof and chimney to look like a mini version of the cottage. The bricks that will finish the job are hand thrown and reclaimed from my chimney and a bread oven. The house was a butchers and bakers years ago so it seems fitting to reuse what I can.

I have attached a few photos and will try and keep this thread updated as much as possible. It seems only fair, that in return for all the info I have obtained from this site, that i let future users learn from my mistakes - of which I expect a few

I would appreciate any questions and criticism to help me along.

My first question (there will no doubt be a lot more to follow) is

I am lucky enough to have the use of a diamond wet brick saw,the sort you normally see on site and have to pay to rent from tool hire companies, and am planning on tapering my bricks as i don't have to rush the job.
I estimate on using 210 but don't want to under order. Has anyone built an oven this size this way and got a better estimate?

Thanks for all the help so far - this site has been a huge help.

Andrew.

[brickie in oz]

Re: 39 inch Pompeii in Lincolnshire England

Hi Andrew, I will be watching your build with interest.

One potential problem I can see is the issue of damp and moisture getting into your base.

[deejayoh]

Re: 39 inch Pompeii in Lincolnshire England

Looks very cool!

My build was similar to yours - 39", tapered bricks. I build the dome around my floor (not on). IIRC, I used about 240 bricks. Wasted a few, but had almost none left over.

Brickie's point is a good one, as per usual. Think about some moisture barrier under your oven. I built my oven slab on grade over a retaining wall, and had concerns about water wicking up. I added Zypex to my slab pour to avoid this.

You also have the risk of water coming in through the vertical walls. You probably should look into waterproofing the back side of the wall around the oven like you would a basement foundation to keep the water out.

Well worth planning on how to keep the thing dry before you build.

[andis]

Re: 39 inch Pompeii in Lincolnshire England

Thanks for the feedback guys.

I hear what your saying and the damp has been my biggest worry.

The concrete did have an additive.
I am planning to treat the back wall with some sort of paintable tanking.
There will also be a second wall at the back with the cavity filled with concrete & additive.
This wall will also have a waterproof sheet behind.
A large soakaway will seperate the wall from the soil so water runs out of the pipes at the front that you can see in the photos rather than backing up behind the wall.

Like you say it's better to try and keep the damp out from the start.
Even with all that I am still not confident it will stay dry but cannot think of much else I can do to help.
Guess I will find out soon if it's worked or not!

[Gulf]

Re: 39 inch Pompeii in Lincolnshire England

"Soakaway"" Sounds like something simular to what we in the US call a "french drain". I reverse installed one on my build. That will help tremenously on the wood storage area. But, a quicker, cheaper fix for the oven itself, would be a waterproof barrier between the concrete hearth and the oven's floor insulation. That is one of those "wish I had done thats" that I did not do .

[andis]

Re: 39 inch Pompeii in Lincolnshire England

Gulf,

That sounds like a good idea. Any suggestions as to what to use and where to place it?
I was planning vermiculite concrete, then calcium silicate board and then firebrick floor.

[brickie in oz]

Re: 39 inch Pompeii in Lincolnshire England

Gulf,

That sounds like a good idea. Any suggestions as to what to use and where to place it?
I was planning vermiculite concrete, then calcium silicate board and then firebrick floor.

Said in my bestest Gulf voice.

Arhhum.
Id put a plastic sheet over the entire concrete base, Id also make it go up over any retaining walls.
Even though you have additives in the concrete you cant keep any oven dry enough.

Y,all.

[deejayoh]

Re: 39 inch Pompeii in Lincolnshire England

a quicker, cheaper fix for the oven itself, would be a waterproof barrier between the concrete hearth and the oven's floor insulation. That is one of those "wish I had one thats" that I did not do .

If there is an anti-wicking additive in the concrete, it seems like that should do the trick, shouldn't it?

[V-wiz]

Re: 39 inch Pompeii in Lincolnshire England

Wow i love the brick on the house. Very nice start, i look forward to seeing the progress.

[Gulf]

Re: 39 inch Pompeii in Lincolnshire England

If there is an anti-wicking additive in the concrete, it seems like that should do the trick, shouldn't it?

That is probably fine for most ovens. But, I think that an oven built into a retaining wall goes beyond wicking. If the ground behind the oven is water saturated, there are hydrostatic forces pushing the water. Soakaways (french drain), and concrete additives are all great. But the plastic barrier, placed like Brickie is suggesting, would be cheap insurance. It definately wouldn't hurt.

GoodaYa'll

[brickie in oz]

Re: 39 inch Pompeii in Lincolnshire England

GoodaYa'll

Too many vowels Gulf, its said G'day with your lips just barely open so as to stop the flies getting in..

[UtahBeehiver]

Re: 39 inch Pompeii in Lincolnshire England

Andrew,
What a nice country setting. While the pros were focusing on the wicking issue i did notice your mockup did not seem to have a reveal on inner arch. Be sure to incorporate one for you oven door to seal. Good luck, watching your build with interest

[V-wiz]

Re: 39 inch Pompeii in Lincolnshire England

However basements are built thats how you should do so also. Special spray on and brushed on mastic. Also they use waterproof nylon on a roll

[ATK406]

Re: 39 inch Pompeii in Lincolnshire England

I'm going to jump on the band wagon here and congratulate you on what looks like a lovely home and build site. I really like the corbelled base.

In addition to what Russell said about the reveal at the entryway, I would recommend that you plan to chamfer your vent opening in your arch to make a more fluid transition of the smoke to your chimney. I recognize that phase of the project is some way off, but I thought I might chime in before anything was set in stone (or brick as the case may be).

Again, congratulations on a great start to a beautiful outdoor kitchen.

Regards,
AT

[andis]

Re: 39 inch Pompeii in Lincolnshire England

Thanks for the advice and compliments... they motivated me to do a little more today!

Utahbeehiver - The bricks were laid out just to check that the oven would fit on the base. I intend to include 2 reveals. One between the dome and the chimney and another where the firebricks meet the wall of the house.

I was thinking of making the arch step from 18" by 11" at the dome entrance, through to 19" by 12" and ending with 20" by 13" at the outer exit if that makes sense. Is this a good idea and do the measurements sound right?

After a bit of research I ordered a 25KG tub of Tanking Slurry. It's a powder you make up with water and apply to brickwork. Safe and non toxic and does just what I need. It forms crystals as it reacts with water and makes a waterproof barrier. I may still plastic sheet the job as well.

Checked how many bricks i needed for the floor. The dome will sit on the floor. 50 should do it. Still cannot settle on how many to order for the whole job. I will cut a few I have and see how the idea of tapering all the bricks grabs me before i order the rest.

I also knocked up a folding base plate and a basic IT. Crude but hopefully functional. Thought this would help keep the floor clean during the build but I may also use a small set of formers on a stand if the angle of the dome makes the IT difficult to use higher up. Could the formers be made a little shallower to compensate for the 1" extra the IT pivot point will add to the dome height?

I can almost taste that first pizza