Ottawa Oven - Onward Once More!

[sarah h]

YaHOO!!

We finally got up and running again! After being stalled for so long it was hard in some ways to get the momentum going again but the dome is now covered in vermiculcrete and it's great to be 'back in the saddle again'.

We'll have to buy some more vermiculite since what we had didn't quite finish it but I need time to decide on a lintel, the chimney and a few other things.

Does anyone know if vermiculcrete on top of my metal vent will be a problem? Will the metal expansion when the oven is fired bust the insulation and whatever's on top of it?

We've definitely decided to keep the dome effect but I can't decide on a finish. I'm now leaning toward stone ...

[gjbingham]

I would suspect that the expansion of the metal would crack the vermicrete. Once that has occurred, you should be able to complete your finish. A crack in the insulation should not be to detrimental, though it will continue to expand and contract with thermocycling.

I'm probably wrong, but I don't see any great reason in insulating the arched entryway. You will loose most of your heat from the floor of the oven. The arch to chimney section probably gets as hot as any part of the dome. You're not cooking there (normally) unless the oven is too hot. I didn't insulate mine.

[SpringJim]

Coming along nicely Sarah!

If you have the stone, I'd go for it....stome is just great to cast your eyes on!

Can't wait to see some cooking.

Jim

[Frances]

Sarah, good to see your oven again!

Stone would be beautiful, probably really good protection against cold weather, too.

How's the cooking/baking going?

[james]

Very Nice Sarah,

How does she (he?) handle when you are cooking? Good in the curves?

I have one question. Do you have solid mortar or concrete to seal the area between the steel vent and the oven dome? That is a place where smoke will try to escape, so you need something solid and permanent there. I'm not sure that vermiculite concrete will last at that spot.

James

[biondoli]

Hi Sarah,
I have the same 2 questions you have as I am at the same stage...I am thinking to put some ceramic blanket around the steel chimney pipe, just 1-2 inch tall, then cover with heat mortar and then start covering all with vermicrete before the finish...I thought that the blanket is soft enough to allow the expansion without cracking the vermicrete...
Regarding the finish I was also thinking to finish the dome with river rocks but then I changed my mind and I am thinking to cover with red thin bricks the arch (the ones they use for house siding) and simple mosaic for the dome. I'd like to keep the dome shape as it is unusual here where I live.
Unless I change mind again! Good luck with your choice.

[sarah h]

Thanks everyone for the input. As for your questions, I can't comment on the cooking because I'm still not back at it yet . It was just too much of a bother while it was tarped over the winter and now, with the blanket & vermiculite layer, I've been waiting for things to dry before doing some re-curing fires.

James, you mentioned sealing the area between the steel vent and the oven dome, where smoke could try to escape - I will do my best, however, if there is a gap somewhere and smoke seeps into that area, is it a major or minor problem?

Opportunity knocked on Friday and so it looks like the dome finish will be stone. Neighbours across the street had a flagstone terrace done in their yard and on Thursday evening, I noticed that one of the workmen was shovelling chunks of leftovers into a rubble bin. A quick call on Friday morning got me the go-ahead to take what I wanted, however, I was told a truck might happen by to pick up the rubble bin at any time. I left work, raced home, and proceeded to kill my back while lugging bins of stone since the only available wheelbarrow had a flat tire. Worth it though, and the back has since recovered.

Yesterday, we went round to a few stone places in search of a lintel and came home with a beautiful chunk of rock identified as 'ledgestone'. Things just seem to be falling into place!

Here's a photo of the flagstone bits - sizes vary from a few inches to about a square foot. I'll post a pic of the lintel rock later today.

Sarah

[SpringJim]

I think that will give you a great looking oven...
...way to go, I love recycling stone!

[nissanneill]

Hello Sarah,
your stone over here is quite popular and in fact I built around 40 metres of retaining wall using a similar material. I got mine from a quarry that went broke called Wistow Stone and I laid it horizontally in a bookleaf pattern. When I put in an inground fully tiled pool, the retaining walls were extended and are around 1500mm high, reinforced with conctrete between the stone and a brick backing, this time from another similar quarry at Kanmantoo.
I am also pondering on the final layer of my 40" Pompeii as it just rendered over 3" of vermiculite insulating cement.
I have been leaning towards mosaic tiles but the trend today in tiles are 4" square and the 2" that I desire almost impossible to find in any colour with the exception green or blue pool tiles.
I am now considering either using the same stone or simply adding colour to another render layer, - quick and easy.
If I use the stone, it will need to involve a lot of cutting to be only around 1 to 2" thick as I am not keen on a slate, random style pattern.
We have on one of the roads entering the city of Adelaide, a dozen or so concrete 'Aboriginal humpy' style concrete structure that are tiled in the same stone. I need to take my camera and get some pictures to show the forum as they look like a group of Pompeii ovens in a paddock.
Keep the pictures coming as I will be watching with interest. Winter is almost here and I won't be doing much more to the oven for 4-6 months as I have the patio and kitchen to construct.
All the best with your stone work.

Neill

[sarah h]

Forty metres - Neill, that's ambitious! But what's a bookleaf pattern? Post a pic sometime, and of the 'Aboriginal humpy' too, as absolutely no picture comes to mind of what that might be ... sounds intriguing though.

I went with the stone because it sort of fell into my lap but I would not want to do all that cutting in order to get the right size of stone. You've got a few months to think that one through!

So you have a kitchen to construct - I have one waiting for demolition, then a re-build. Plans are to start as soon as the oven is done, at least to the point of being fairly weatherproof.

Good luck with your projects.

Sarah