Barrel Oven - Planning

I've already written a bit about my enthusiasm for ensuring we have something other than a camp stove and an open fire to cook on during the build of our house. I've done that before for large groups of people and I'm not keen to repeat the experience over longer than a weekend. It also seems fairly obvious that the key to ensuring we have willing and happy helpers is to keep them well fed (the whole build will go smoother with full bellies). So I don't think it's unreasonable to spend quite a bit of time and effort ensuring this is taken care of - I consider it good project management.

One of our strategies is a barrel oven:

I've seen a number of accounts on various blogs from people who've built their own ovens, including making the metal parts themselves, but they're all a bit light on detail about how they did the metal bits. Others simply purchased the metal parts from Firespeaking and just built the oven around them. Since the latter isn't an option for us (even if Firespeaking shipped to Australia I think the postage on something as heavy as this would be beyond what we'd consider worth it) we'll build the whole thing ourselves from scratch and keep an account of it here for anyone else who wants to do the same.

In the planning stages there are some fairly obvious requirements, and the rest we'll make up as we go along.

The pieces we'll need to make out of metal before we begin building the oven are:

• Ash grate
• Ash drawer
• Firebox door
• Barrel with slots for drawers
• Barrel door
• Shelves
• Chimney with baffle

We're fairly sure we'll need the following equipment:

• Welder
• Angle grinder
• Metal file
• Measuring tape
• Spirit level
• Hammer

We already have all of these, most of them purchased with this project in mind but knowing they'll be useful for others down the track. We don't yet have safety equipment for the welder though, so we'll need to get two sets of welding masks and gloves and leather aprons and so on before we can start.

And the following supplies:

• Lengths of angle iron (x many)
• Steel rebar
• Clean 55 gallon drum
• Thin (ish) steel sheets
• Various scrap strips of steel (handles etc)
• Hinges (both for firebox door and oven door)
• Ceramic fibre insulation
• 6" diameter metal pipe (chimney)
• Bricks
• Mortar
• Gravel (under foundation)
• Cement (unless we find a better foundation)
• Wood offcuts (for arch moulds)
• Large nails (for rivets)

Most of these bits and pieces are likely to be sourced from the local tip, and I'll keep track of how much it all costs us. We'll start with the ash grate as that is likely to be easiest (plus we have the bits for it already).

Very rough plans for a little house

The inspiration for our current plans are largely based on a design by Owen Geiger at the Natural Building Blog. I don't know if anyone has ever built this house design (whilst plans are available from the site, it's not clear how many people have purchased each one let alone built it).

I ditched the curve fairly early on, for simplicity's sake, though it means putting in buttresses to support the walls. This was helpful initially doing drawings and sketches, but more recently I've wanted to add them back in again. At first I diverted quite a long way away from the original layout, and found myself coming back to it with each drawing. Eventually, the only addition was lofts.

Currently these plans have been done just by me in SketchUp. Ultimately we'll need to involve an architect, or a structural engineer at the very least. But we want to have a very clear idea of what we're asking for before we do, as it's unlikely we'll find people who have experience with this kind of building. Given the overall project it's also important that either Kyle or I (or both if possible) have a pretty solid understanding of the whole thing and each of the features we want to use so that we can take advantage of recycled materials we find, and if something doesn't happen as planned during the build we can improvise effectively.

I'm not really convinced by the split levels in the roof. I did it that way at first, so we could have a loft on one side, but in hindsight I think it'll be easier to have the whole roof at the same level and have lofts on both sides. The split is likely to be a weak point for leaks, and difficult to put together. Then you need fancy bits for guttering, and the higher the roof the less restricted you are in terms of water flow into tanks given the loss of vertical height in leaf traps and first-flush diverters.

There are a lot of details still to iron out. I'd like it to be a bit smaller overall, but we'll have to work on the layout a little and work out how attached we are to our current furniture. For example, we have a big purple couch at the moment. We love it dearly, chose it very carefully, and use it thoroughly. But, we could have a couch that is also a rocket mass heater. Having such a large object fulfil multiple functions makes good sense in a small house. In-built furniture has other benefits, you can work ventilation around it more easily, it can be structural support for something, and you don't have to worry about the fabric fading in the sunlight (not that I did anyway, clearly I make a poor homemaker).

So it will be a little while before our development application gets made, but we have a start. Aside from the house plans there are other plans, like the composting toilet application and solid fuel heater application if we do decide to put in a rocket mass heater (seems a no-brainer to me).