Ready to Role Up My Sleeves

[swripley]

Greetings all from cold, snowy south central Montana, we just had what I greatly hope will be our last snow of the season so that I can getting started on my oven project. But more likely it will be at least another month.

A brief intro - I am an avid do it yourselfer and cook who baked professionally in a former life. I've been married for 17 years to a man I affectionately call "The Cruise Director". We entertain extensively! My husband is a wine broker and I am the director of Outreach for our local university.

Outdoor brick ovens first caught my attention during trips to the Dry Creek area of California. I have been gathering information on pre-fab units for several years now, but nothing motivated me to take the plunge. Last summer a good friend had a barrel oven built and while I loved the oven, wasn't thrilled with the price. And then one afternoon of internet surfing brought me to Forno Bravo. I download the plans and have been fixated ever since.

I am now on my fourth read through of the plans, have spoken three times with our local building department and located local suppliers for everything I will need. I met with the a rep from the fire department today. I left him looking perplexed and with a complete set of plans for what I have planned. I don't think they get many do it yourselfers building brick ovens in Montana! He said he would have to look it over and would get back to me in about a week. I'm pretty certain I will be able to overcome any concerns he has. I feel ready to role up my sleeves.

My plans have expanded to include a fairly extensive outdoor kitchen. Never lacking in confidence, I have a tendency to think there isn't anything I can't do. But I have been known to get it over my head on occasion. I've been emailing James over the last several weeks and he directed me to this forum. Imagine my excitement - a whole group of people who seem to be willing and able to help me out if I get in over my head. Any everything I've read so far has been greatly inspiring!

My initial questions are: 1) I am planning a corner installation. What is the best way to install the fourth block course over the wood storage area? I understand the use of angle iron and cutting out the 3/8 to accommodate its thickness, but how to I handle the void that remains on the side walls by tying into them at an angle? Should I miter the corner blocks? Should I extend my framing lower and fill in the wedge when I pour the structural concrete layer? Or am I better off no having a row of blocks over the opening (they way gaptogap did on his recently posted photo)? Or is there a better alternative someone can offer? 2) The diagram on page 15 of the plans shows a 62” outside measurement on the 43” oven, what does this reference? Based upon everything I read, I was anticipating a 72” block stand. However, the corner installation on page 19, photo 2.3 of the plans looks like it is 80”. What is the best stand size for a 43” corner oven? 3) What’s the best way to finish the roof on a corner installation? A gabled roof that will accommodate the front angled wall could get tricky. I am leaning toward enclosing with concrete block and stucco. I like the roof on the Stucco House on page 49 of the plans but am concerned a flat roof may not be a good choice in my northern climate. Anyone have a recommendation? 4) Does anyone have a strong opinion to offer on what’s is a better cooking surface – the four piece pie shape that Forno Bravo carries or fire brick? 5) All of the pictures I have seen posted on this site and others, show ovens built yards that are much larger than mine. I will be building in a fairly tight space and the back of the oven will be right up against a 6' privacy fence. Is this going to be a problem? I'm not concerned about making it difficult to build, I am on great terms with my neighbor and I know he won't mind if I take boards out temporarily to grant access during the building process, I am more concern about problems that might arise when I use the oven.

I think that’s it for know, no doubt I will have a lot more questions as I progress.

Thank you all,

Sharon

[maver]

Originally Posted by swripley

1) I am planning a corner installation. What is the best way to install the fourth block course over the wood storage area? I understand the use of angle iron and cutting out the 3/8 to accommodate its thickness, but how to I handle the void that remains on the side walls by tying into them at an angle? Should I miter the corner blocks? Should I extend my framing lower and fill in the wedge when I pour the structural concrete layer? Or am I better off no having a row of blocks over the opening (they way gaptogap did on his recently posted photo)? Or is there a better alternative someone can offer?

Sharon, welcome to the forum. Here's a link to Widespreadpizza's corner oven for another idea:

http://www.fornobravo.com/forum/8/lo...nt-1598-2.html (looking for opinions/ideas for space please comment)

You can see that he filled the void in the side walls with a column of poured concrete.

Originally Posted by swripley

2) The diagram on page 15 of the plans shows a 62” outside measurement on the 43” oven, what does this reference? Based upon everything I read, I was anticipating a 72” block stand. However, the corner installation on page 19, photo 2.3 of the plans looks like it is 80”. What is the best stand size for a 43” corner oven?

I think you'll find that the variation in stand size is due to variation in how to finish the oven. It's been a while since I pondered the math involved with this, but you first need to decide how you are going to build the 43" dome (firebrick splits cut exactly or roughly, or a 1/3 firebrick thickness, or even a geodesic like DMUM), then whether to add cladding (my opinion is don't bother), what kind of insulation and how much, and any finish materials outside of that. That's your block stand size. It's helpful to develop your vision of your finished oven, then plan accordingly.

Originally Posted by swripley

3) What’s the best way to finish the roof on a corner installation? A gabled roof that will accommodate the front angled wall could get tricky. I am leaning toward enclosing with concrete block and stucco. I like the roof on the Stucco House on page 49 of the plans but am concerned a flat roof may not be a good choice in my northern climate. Anyone have a recommendation?

Your roof needs to prevent water from getting into the oven/insulation and in your case needs to be able to handle whatever snowmass you encounter. In your environment a sloped roof is likely appropriate, but how you slope it is the question. I think a gabled roof would work wall. Whether there is an angle in your front wall or whether you extend a flat wall surface to either side is a design choice. There are less corner ovens to look at for inspiration here, but play around with the ideas for the finish. You are not limited in the shape of the oven by anything more than the space you build it.

Originally Posted by swripley

4) Does anyone have a strong opinion to offer on what’s is a better cooking surface – the four piece pie shape that Forno Bravo carries or fire brick?

Both work - there is supposed to be a thermal advantage to having the dome walls extend around the floor of the oven directly onto the insulation below, although that can also be achieved with carefully cut firebrick. Seams can also be an issue, but that can also be worked around with a 45 degree angle herrignbone pattern and grinding down any seams that don't lie flat.

Originally Posted by swripley

5) All of the pictures I have seen posted on this site and others, show ovens built yards that are much larger than mine. I will be building in a fairly tight space and the back of the oven will be right up against a 6' privacy fence. Is this going to be a problem? I'm not concerned about making it difficult to build, I am on great terms with my neighbor and I know he won't mind if I take boards out temporarily to grant access during the building process, I am more concern about problems that might arise when I use the oven.

We don't take pictures to show how small our yards are. My oven is up against a fence, and several builders have pretty small suburban backyards. You really don't need to access the back of the oven other than during building and perhaps for maintenance in the future (if you have to repair the finish). At no point in use of the oven does the back matter.

Marc

[CanuckJim]

Sharon,

Maver has pretty well covered the ground on your questions. I live in Ontario, where snow load is an issue. I went for a gabled roof for exactly that reason. Unless you have considerable slope on a flat roof, you might be asking for trouble. Any roof you build, however, should be strong enough to withstand the weight of snow and especially wet snow during freeze-thaw cycles. There's a pic of my barrel vault oven in the gallery.

You've really done your homework, so it's time to get busy. Once the snow melts, of course.

Jim

[james]

Great to see you here Sharon,

I know that feeling of "I can do that" -- and it usually works, except that one time I had the roof off the house in the middle of winter. :-)

FB is just up the road from Dry Creek -- all roads lead to Sonoma.
James

[Marcel]

Ready to Role Up My Sleeves
<snip>

(M) Hi, Sharon,

(S) “My initial questions are: 1) I am planning a corner installation. What is the best way to install the fourth block course over the wood storage area? I understand the use of angle iron and cutting out the 3/8 to accommodate its thickness,”

(M) That is the customary method but I tried a different way that may work for you. I used 4 full courses of concrete block, laid a heavy tubular pipe on top of the last course and poured my slab over it. That precluded the necessity of notching and also allowed me greater height access for the wood storage area. Here is an image of that:







(S) “ but how to I handle the void that remains on the side walls by tying into them at an angle?”

(M) You may find Paul Ages corner oven a helpful reference on this site. He has hundreds of postings and many good photos on 20 pages. He, too, is a former professional baker. You may need to do some sleuthing but try starting at:

http://i11.photobucket.com/albums/a1...s/DSC01545.jpg



[IMG]file:///C:/DOCUME%7E1/Marcel/LOCALS%7E1/Temp/moz-screenshot-194.jpg[/IMG][IMG]file:///C:/DOCUME%7E1/Marcel/LOCALS%7E1/Temp/moz-screenshot-195.jpg[/IMG]


http://www.fornobravo.com/forum/f8/p...today-155.html (pompeii oven construction began today)

(S) “Should I miter the corner blocks? Should I extend my framing lower and fill in the wedge when I pour the structural concrete layer? Or am I better off no having a row of blocks over the opening (they way gaptogap did on his recently posted photo)? Or is there a better alternative someone can offer?”

(M) I think James would say that there is no “right” way to build your oven but that some methods are arguably easier. Your decisions will depend upon your uses, layout preferences, and baking priority, i.e. are you more interested in pizza baking or bread baking.

(S) “2) The diagram on page 15 of the plans shows a 62” outside measurement on the 43” oven, what does this reference? Based upon everything I read, I was anticipating a 72” block stand.”

(M) That is the +/- size of my stand and I didn’t need to cut any concrete blocks for it. My oven diameter is 42” and that can easily vary an inch or two and still fit the base.

(S) “However, the corner installation on page 19, photo 2.3 of the plans looks like it is 80”. What is the best stand size for a 43” corner oven?”

(M) I’m sorry to seem like I’m waffling, but again it depends on what other plans and priorities you have. The bigger your hearth area, the greater is your option for extra cladding (should you want that) and insulation on the sides of your dome. But if space is at a premium, you probably need to consider your 72” block stand as a minimum.

(S) “3) What’s the best way to finish the roof on a corner installation? A gabled roof that will accommodate the front angled wall could get tricky. I am leaning toward enclosing with concrete block and stucco.”

(M) If I understand your roof plans I’d suggest that concrete blocks, because of their width, will take away much of your cladding and insulation space. Most builders constructed a framework of light weight sheet metal studs, over which they screwed some kind of non-flammable mortar board like “Hardi-Backer”.

(S) I like the roof on the Stucco House on page 49 of the plans but am concerned a flat roof may not be a good choice in my northern climate. Anyone have a recommendation?


(M) I favor a peaked roof for several reasons in addition to helping snow to slide off. Triangular construction is inherently stronger than square or rectangular (A-frame houses exploit that property) plus the peak will provide you with storage space for poured in insulation over your dome where the heat rises. I also like the look of a peaked roof.

(S) 4) Does anyone have a strong opinion to offer on what’s is a better cooking surface – the four piece pie shape that Forno Bravo carries or fire brick?

(M) Are you going to be primarily baking pizza? If so, than the Forno Bravo is arguably better; if your emphasis is on bread baking, perhaps the thicker fire bricks may retain heat longer. Whatever the difference, it is probably very small.

(S)5) All of the pictures I have seen posted on this site and others, show ovens built yards that are much larger than mine. I will be building in a fairly tight space and the back of the oven will be right up against a 6' privacy fence. Is this going to be a problem?

(M) Not as far as fire danger if you house your oven and insulate it properly.

(S)“I'm not concerned about making it difficult to build, I am on great terms with my neighbor and I know he won't mind if I take boards out temporarily to grant access during the building process, I am more concern about problems that might arise when I use the oven.

(M)I suspect a tall, well constructed chimney will eliminate most of such potential problems

(S) “I think that’s it for know, no doubt I will have a lot more questions as I progress.

Thank you all,

Sharon”

(M) I have posted over 90 images of my oven build on PhotoBucket. If you check that out you need to know that I abandoned some processes so not all of the chronology will make sense at:

marceld - Photobucket - Video and Image Hosting

Ciao,
Marcel

[swripley]

Gentlemen, I am overwhelmed! Thank you for your incredibly quick and helpful responses.

Maver, thank you for sending the link to Widespreadpizza’s corner installation that is exactly what I was thinking. The photo really helped solidify it in my minds eye. A question – when you reference cladding, which you say not to bother with, do you mean additional high heat mortar to the outside of the dome? Cladding is a term I haven’t ran across yet.

CanuckJim and Marcel, I hear your warnings about the flat roof, but am not ready to give up on it quite yet. I’m not to concerned about the load as our snow fall isn’t nearly as bad as Ontario’s and there are a lot of flat roof buildings in our community, but I want to be certain I guard against pooling water. I will work on determining the right slope and perhaps incorporating a gutter system to help shed water.

Marcel, this may be a silly question, but how do you attached the metal framing to the hearth? The plans talk about attaching concrete board to the metal studs but nothing about attaching the bottom plate to the slab. I have seen a tool the shoots nails into concrete, is that what I would use?

All, a question about insulation, I have used a product in the past for fusing glass in a kiln called Ceramic Blanket by Thermal Ceramics listed to 2500 degrees. It looks very much like the Insulfrax in the Forno Bravo plans. Anyone heard of it? Have an opinion whether it will be a good substitute?

Thank you all again!

Sharon

[jengineer]

yep Thermal Cermics 2500 blanket for insulating the dome will be a fine sub for Insulfrax (not sure of the new name James is using)

[Marcel]

[IMG]file:///C:/DOCUME%7E1/Marcel/LOCALS%7E1/Temp/moz-screenshot-196.jpg[/IMG](S) "CanuckJim and Marcel, I hear your warnings about the flat roof, but am not ready to give up on it quite yet. I’m not to concerned about the load as our snow fall isn’t nearly as bad as Ontario’s and there are a lot of flat roof buildings in our community, but I want to be certain I guard against pooling water. I will work on determining the right slope and perhaps incorporating a gutter system to help shed water."

(M) Here is an image of Paul's shed roof from his corner oven, at:

http://www.fornobravo.com/forum/8/po...ay-155-15.html (pompeii oven construction began today)

(M) There is another, below it, from the side, at that URL. Paul even grows herbs (some for his pizza) on that roof. There is no requirement to build a peaked roof. It looks like Paul used Durock rather than Hardi-Backer. Durock tends to crumble on the corners. Hardi-Backer is available in quite a thin sheet and is totally impervious to flame.

(M) We're WAY ahead of the process but in case I forget to mention it, be sure to clad your sheet metal stud WALLS BEFORE you attach your roof. If you have any roof overhang it can be very awkward to try to insert screws under that overhang. Also, having pre-clad your walls with Hardi-Backer you will have given those walls additional diagonal bracing that will make the roof installation easier.



(S) Marcel, this may be a silly question,

(M) A "silly" question is an oxymoron. If I were judged by the number of so called silly questions I've asked, I'd be consigned to a mental institution!

but how do you attached the metal framing to the hearth? The plans talk about attaching concrete board to the metal studs but nothing about attaching the bottom plate to the slab. I have seen a tool the shoots nails into concrete, is that what I would use?

(M) You could use such a "gun" but I know of no masonry oven builder who has gone that route. Those guns are typically used to attach a wooden 2x 4 sole plate to an existing slab floor.

(M) If your hearth slab will have refractory concrete as it's top layer, then, as soon as your 2 part hearth slab sets up even for a day, get ready to install your horizontal "sole" plate(s) of sheet metal. I say ASAP because my concrete hearth slab was so hard I could barely get a carbide bit to set the holes for those blue case hardened concrete screws. Note that I used the old plan order of layering, i.e. insulation on the bottom and refractory re-bar reinforced concrete on the top. I plan to do more bread baking than pizza baking so I welcome the extra heat retention of that arrangement.

(M) I believe you can see the 2 concrete layers, from my oven, in the old plan's orientation in the next image:



(M) 1- I cut the horizontal channels to the full length of each side of my slab. 2- I removed the resulting tab so that the next channel could overlap the first. 3- I determined where to drill through the sheet metal channels and used a conventional drill bit to make those holes since a masonry bit won't cut steel very well. 4- I relaid the horizontal channels, changed to a masonry bit and pre-drilled into my top layer of refractory concrete.

(M) If you decide to employ the new orientation, i.e., insulating concrete on top; (I call it Perlcrete or Vermacrete) then there should be no rush to set those channels as that insulating layer is FAR softer. You would need to ask another builder how to proceed if you substituted heat resistant sheet insulation like Insulfrax or Refrax. as I have no experience with that.

(M) I used the hex head type and installed them with a electrical screwdriver with a hex nut driver bit to minimize slipping.

(M) Since my colleagues on this site are probably tired of seeing my repeated images, consider emailing me directly to marcelde@efn.org if you have any specific questions.

(M) Take it Poco a Poco. The trip is the thing.

Ciao,

Marcel

[maver]

Originally Posted by swripley

Maver, thank you for sending the link to Widespreadpizza’s corner installation that is exactly what I was thinking. The photo really helped solidify it in my minds eye. A question – when you reference cladding, which you say not to bother with, do you mean additional high heat mortar to the outside of the dome? Cladding is a term I haven’t ran across yet.

You got it. Additional mortar or any other noninsulating material designed to give the dome a larger thermal sink. The downside is slowed heat up times. I think for home oven any way to shorten the firing time without sacrificing ability to cook is important. Too much reduction in heat absorbing capacity and you might have trouble with retained heat baking. I'm watching with interest other builder's reports on thinner domes, but I suspect anything in the realms I presented in my earlier post for dome thickness will be fine for retained heat baking. For a home oven, 1-2 batches in a 40+" dome is a huge capacity and hard to use it all.

Originally Posted by swripley

Marcel, this may be a silly question, but how do you attached the metal framing to the hearth? The plans talk about attaching concrete board to the metal studs but nothing about attaching the bottom plate to the slab. I have seen a tool the shoots nails into concrete, is that what I would use?

There is a tool called a rotary hammer or rotary drill. It looks like a regular drill but it hammers while rotating. It can drill through well cured concrete very easily. Place plastic anchors into the holes (readily found at any hardware store) and screw into the anchors. No need to shoot anything. Find a friend with the rotary hammer or rent one for the project, or do DMUM's ebay rental - buy and then sell on ebay after.

[Versachi]

Just to add to Maver's post about the hammer drill or shooting pins into your concrete to hold your steel track. I work with steel studs almost everyday we are constantly anchoring into concrete. In construction, shooting pins is more common because we can move along much faster that way but it can be a little tricky and dangerous if you don't know what you are doing. With your metal track so thin it can be a challenge to correctly set the depth of the pin so that it anchors the track without going through it or to shallow that it doesn't hold. Also if your shot is on somewhat of an angle you can have ricochets. You won't kill anyone but you don't want your neighbor to lose an eye! As Maver pointed out renting or borrowing a hammer drill is your best option. Plastic anchors with matching screws in the corners and every 2-3 feet along your track will be more than enough. It is common in commercial construction to see screws used that are meant just for concrete. Tapcon's are a popular brand name. Just drill your hole and screw it in. They are as or more reliable than plastic anchors IMO! For both options 3/4 or 1 inch screws will hold the track in place just fine.

Good luck, Versachi (still 2 feet of frost so not building yet for me)