Forno Bravo Forum: The Wood-Fired Oven Community

Forno Bravo Forum: The Wood-Fired Oven Community (
-   Outdoor Fireplace Design (
-   -   SPRING!!! and a new project (

cvdukes 03-04-2008 09:17 PM

SPRING!!! and a new project
We did a spur of the moment pizza party this weekend (16 pizzas). By the end of the evening, the temps were dipping back into the high 40's. Observing the traffic flow of my guests and where everyone was huddling up, its led me to my next project.... a monster fireplace unit made of ferro-cement (hey, its worked for my pizza oven, so why not?)... Think basically a huge Chimenea on steroids.

I've got a lot of terrain issues to deal with around the party area: Last year, this was a totally unusable slope on the back side of my pond's dam. Through a little judicious cutting, digging and terracing, I've been creating flat space for gatherings. The pizza oven is part of a larger oven complex with countertops that now form a retaining wall holding up part of the dam. Just beyond the oven complex, I've created a a small terrace about 16 feet long and 10 feet wide. Right now the terrace is held up by a temporary system of pine logs and itís always been my intention to replace them this spring with permanent construction. The working plan up until Saturday has been that a small metal Chimenea (we've had for years) would sit in the middle of the terrace.. The idea has been that seating would be built into the uphill and lower terrace walll facing the chminea for those cooler evenings.

Well, the little chimenea was roaring away Saturday, but it didn't really attract the party. Looking at how people were gathered, there simply is not enough room on that portion of the terrace for the number of folks with the chimenea plopped in the middle of the space. That, and it doesn't throw enough heat to allow people to sit back from after a few quickie measurements and a beer-fueled consult with one of my engineer friends at the party, the decision was reached to construct a fireplace in the upper terrace wall so it would radiate heat out onto the space. The fireplace and counters on either side of it will form a retaining wall for the remaining section of the dam in that area.

Initially, my thought was to get a couple cubes of bricks delivered and do a full masonry unitÖ but I learned to really hate laying brick when I built the oven complex because I donít have the patience to do it right. A little more thought about the amount of concrete I would need for the size of foundation that Iím envisioning (plus, it has to all be transported down there by hand) and just the sheer cost of a brick structure convinced me thatís not the way for me to go.

Sunday morning it came to meÖuse my old favorite ferro-cement. From my pizza oven, I know it can take the heat plus this wonít be running anywhere near as hot. After a few sketches, I headed out to garage and started bending some hog-wire into the preliminary frame. Between the time Sunday and a little bit of time this evening (maybe 4 hours total), I pretty much have shaped the armature into a close approximation of the final shape. Iíll have to spend a few more hours fine-tuning the shape before I cover it with chicken wire but everything should be ready for the concrete in a couple of weeks.

The monster ought to weigh in around 600 pounds once its finished. Iíll do the wire framework in the evenings in the garage, but Iíll have to set it up in its final place before I do the concrete. I figure itíll probably end up costing ~ $150 for wire and concrete for the fireplace and chimneyÖand Iíll have get wire mesh doors made, but that shouldnít be too bad.

Iíll take a few photos once its covered with the chicken wire because the hog-wire frame doesnít show up too well on pictures. With everything else that is on the to-do list, it really won't be finished until late Summer, but I probably don't need that amount of heat again til Ocotober.

gjbingham 03-04-2008 09:54 PM

Re: SPRING!!! and a new project
Looking forward to the pics. You paint a great picture with words, but one photo would explain a lot.

Acoma 03-13-2008 08:07 PM

Re: SPRING!!! and a new project
What's the latest on the outdoor heat source? I am peaked with interest.

cvdukes 03-13-2008 08:53 PM

Re: SPRING!!! and a new project
Right now the wire armature is still occupying space in the garage. I got it covered with the chicken wire layer on the inside and two layers on the outside. Went out to shoot some pics of it, but the batteries were dead in the camera...
Now I'm having to tie the layers together to make the thickness less than an inch. Using some galvinized electric fence wire for the ties... a little too stiff to do easily, but the stuff is too hard to use around the yard so its either use it here or toss it completely.
I'm about half through with the tying step...haven't been working on much as I would like because the wife's insisting that I help weed all the flower beds I put in years ago, then she's going turn me loose in the veggie plot too (side note: she's doesn't like the idea of me just being R&D and her being O&M...figures that if I create something, I'm supposed to take responsibility for the upkeep )
So far cost is $21.00 for the chicken wire. The hog wire for the armature was picked up off a neighbor's trash pile, so nothing there. Probably 10 hours invested so far. Right now its 7 feet tall (height of the garage door)...once I get in place, I'll need another small roll of the chiken wire to extend the chimney another 4-5 feet.
Kid coming home for spring break tomorrow. Don't know his plans for next week, but if he can be drafted for a day, I may try to get it mortered. It'll be a lot easier if I can have him on the inside as I push the mortar in from the outside. Of course, also have to replace the pool liner so I'll to figure which job I could best use him on....chance of getting him to work on both is not too high.

cvdukes 03-16-2008 06:18 PM

Re: SPRING!!! and a new project
1 Attachment(s)
Decided that I would take advantage of my son being home from college this week by enlisting him to help mortar the monster chimena. The way I figure it, I can get friends to help with the pool liner a lot easier than trying to get one of them to climb up inside the chimena while I apply mortar to it. Towards that goal, spent a few hours today doing all the wire tying. See attached picture. Still have a little bit of wire tying to do at the bottom of it and around the door openingÖ maybe 2-3 hours at the most.

Plans for the week are that Iíll do the rest of the wiring over the next couple of evenings and then take off the last half of the week. Wednesday, Iíll make the foundation and then do the mortar packing on Thursday. Unlike typical ferro-cement projects that have to be mortared all in one day, Iím thinking I can do this in a few stages. Iím planning on doing a skim coat of fiberglass-cement on both the inside and outside after its all mortaredÖthat should counteract any weakness from doing it in stages.

Right now the monster is 7 feet tall and 33 inches front to back. Total width is 42 inches. The door opening is 36 inches wide and 38 inches tall. The chimney opening squeezes down to 14 inch diameterÖ the next sections will take it down to 12 inches so that should be right ratio of chimney to opening size.
More pictures to come as progress goes on.

Inishta 03-16-2008 09:01 PM

Re: SPRING!!! and a new project
Very interesting project CV. Kids come in handy now and again.


Frances 03-17-2008 03:38 AM

Re: SPRING!!! and a new project
Interesting, this is about what I'd planned for my grill/firplace thing sometime in the hazy future... What kind of cement are going to be using?

And in an asside, do you know of any good sites on Ferrocement by any chance?

Keep the pics coming, I'd love to see how this turns out!

cvdukes 03-17-2008 04:55 PM

Re: SPRING!!! and a new project
The concrete to pack into the wire will be just standard pre-packaged mortar mix. After that cures (a couple weeks of slow cure under plastic), I'll use the fiberglass-reinforced surface bonding concrete to skim coat inside and out. At that point, decision time...when I made the pizza oven with the ferro-cement, I coated over the inside with a mixture of fireclay,sand,powdered kaolin and portland (my own mixture). I'm waffling about repeating for this. I don't know that I really need the inside coating, by why argue with sucess? I don't have enough fireclay or kaolin on-hand to do all of the inside of this project. Only place in town that sells fireclay is one of those places open only monday-friday during the day...and about 30 miles from work so highly inconvenient. The local feed and seed sells the kaolin, but only during shrimp season in the late fall, which may work out okay, becasue I probably won't need the heat output til then anyway,but I would like to mark this finished before then.
I haven't found any good sites on ferro-cement but there have been a couple of good books in print on the subject I was able to get though my state library system.
BTW, had a chance to ride by our old house last week and was able to peek over into the backyard. The first ferro-cement project I ever did (24 years ago) was a free-form retaining wall holding up a sand-concrete patio. From the looks of things, both have stood the test of time well.

Frances 03-18-2008 01:55 AM

Re: SPRING!!! and a new project
Sourcing materials is always a bit of an adenture, isn't it? I'm going to use some of my left over fire bricks for the inside of the grill.

Do you remeber which books on ferrocement you found most usefull? My favourite at the moment is Sherri Warner Hunter's "Creative Concrete Ornaments of the Garden" - but it'd be nice to have more info, especially on larger instalations... :)

The problem here is, there don't seem to be many books on the subject in German, and English books I have to buy outright before I can read them...

cvdukes 03-18-2008 03:41 PM

Re: SPRING!!! and a new project
I know I read everything on the subject in our state library (I can have them sent to my office so its convenient). When I get on kick for somthing, its not unusual to go through 40-50 books a month. Some of these are pretty old (dating from the late 40's) and I can't remember if any were particularly useful.
Don't limit yourself just to the garden books...same techniques for boats, roofs etc.

Just looked at their card catalog... Titles they had that I must have read are

Reinforced concrete : mechanics and design / James G. MacGregor.

Reinforced concrete fundamentals, with emphasis on ultimate strength.
Ferguson, Phil Moss,

Simplified design of reinforced concrete, by Harry Parker ...

Ferrocement : building with cement, sand, and wire mesh / Stanley Abercrombie.
Reinforced concrete reservoirs and tanks / G. P. Manning
Design and construction of concrete shell roofs [by] G. S. Ramaswamy
Basic reinforced concrete design : a text-book for students and engineers / by Chas. E. Reynolds
The theory and practice of reinforced concrete [by] Clarence W. Dunham.

Ferrocement boat construction.
Cairncross, Chris

Concrete boatbuilding; its technique and its future, by Gainor W. Jackson, Jnr. [and] W. Morley Sutherland. Illustrated by Gainor W. Jackson, Jnr.

If any catch your eye, let me know and I can obtain it for a quick browse thru to see if it has value.

All times are GMT -7. The time now is 10:46 AM.

Powered by vBulletin® Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
© 2006/10 Forno Bravo, LLC