Shed Project: Finished!

This is the shed that the internet built.

The Pozible launched on the 27th of February and I started foundation work on the 3rd of March. We poured the slab on the 12th of April, 41 days later. There was a lot of shoveling between those two dates. I had most of the structure up by the 20th of April and then declared it finished on the 22nd of May. It is now almost set up, with the workbench, table-saw, metal mill and metal lathe all installed. But there is just the small matter of 15 square metres of floorboards to do something with.

This has been a really fun project and quite life-affirming. It’s really great to have people support your ideas. Not just financially, which is obviously excellent, but in conversation. Saying “I am crowd sourcing a shed” to someone and receiving “woah, that’s great” in return, started a lot of interesting conversations and has put me in touch with people I probably wouldn’t have found otherwise.

I have also really enjoyed seeing the way people have wanted to engage in doing things together. A lot gets said about computers and facebooks that reduce some of our interactions, but you’ll be surprised by the number of people who think that spending a day pouring a slab of concrete sounds excellent. We’ll put it on facebook later, but people still want to do things, and they want to do them together.

Knowing this I will definitely pursue some avenues to teach people things in the shed. Making things is empowering and sharing skills and experiences is the essence of community. It was obvious during this project that one person can do a lot, but two can do a lot more.

Construction wise the rest was pretty simple. All the walls were in place, I had made sure the internal surfaces were (mostly) in the same plane and they were all timber so fastening was a breeze. I am actually going to write a post on fasteners soon, but until then I really liked using stainless decking screws with square drives. They’re easy to use in soft wood and look good enough not to bother concealing them.

Below then is the great unveil, with some commentary. Thanks.

2014-05-03 12.32.18I insulated all the walls with earthwool, partly just because it was so cheap. About $75 insulated all the walls, compared to about $2k to do the walls in our old place after they had been built. It was a powerful lesson in “materials are cheap, labour is expensive”.

2014-05-03 12.32.25 I planed all the boards for the long wall with a terrible power planer. I had about half the boards required to do the wall with unpainted wood from when I bought them, and decided it would be worth doing enough for the whole wall. I didn’t like the idea of sanding or paint stripping so used electricity and whirling blades. It’s a bit rough in places, but it really does just add to the character.2014-05-04 14.12.57 2014-05-07 16.36.53 2014-05-07 16.47.512014-05-09 12.26.40I cut a couple of sheets of ripple iron I picked up from the Tip Shop and was really happy with the cut.

2014-05-12 14.37.12I used some of the coloured boards vertically on the end walls.

2014-05-22 19.13.09This is the nook where the workbench lives. That brace board is a great material. Very cheap, made from forestry waste and terrific in tension. There’s those cedar mouldings too.

2014-05-18 09.56.10 2014-05-18 10.50.53 2014-05-19 18.04.19I made some barn doors for the front. They worked out better than expected.

2014-05-22 19.14.292014-05-22 19.13.21You can see here that some of the boards are a bit wonky. I decided to leave it, and just accept them. These are 120 year old boards, probably cut by hand. They’re a bit wonky? well what a surprise.

2014-05-22 19.13.31 2014-05-27 20.48.05What it looked like after a week.



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Shed Project: Construction phase

By this time I had settled on a post and beam construction method. The major structural elements would be vertical timber posts supporting horizontal timber beams. These are sized to hold a lot more than their own weight and the remaining construction elements added around them.

Post and beam construction is simple and easy to comprehend, but requires some particular thought to manage flex. I’ve written before that the goal of building things should not be ‘will it stand up’ but ‘will it flex under load’ and post and beam requires some thought to prevent flex.

2014-04-18 15.01.05Consider the most basic post and beam construction; 4 posts in a rectangle, supporting 4 beams between the tops, with each post 2m tall and each beam 2m long. A load straight down on top of this structure would be fine, the posts resisting compression easily. But if the force isn’t directly down, say at 45 degrees this structure is in trouble.

Each of the points where a member joins something can act as a ‘plastic hinge’. They’re not actual hinges, but the flex in the material allows them to behave as one. Consider a single post bolted to concrete with a metal post stirrup, and apply a force horizontal to the ground, at the very top of the post. The wood will flex a little along it’s length, bowing and allowing the top to move, but also the metal stirrup is subject to a huge rotating force, which we like to call a ‘moment’. So while every component might be securely fastened, there is still considerable flex.

2014-04-19 11.15.33Reduce this theoretical structure to just two posts and a beam between them. Push it sideways at the top and it will flex so that the corner you are pushing  gets closer to the bottom, opposite corner, with the other pair of opposite corners getting further apart. To resist this force, it is normal to use a ‘tension member’, a cable or strap of steel that doesn’t really stretch in that force range. If you put one of these between each pair of corners, you can resist this force in both directions. So I put up my posts and beams, then systematically removed all of the potential bad forces by screwing on ply, sheet steel, steel straps and the magnesium oxide sheets.

It was an interesting process, watching how an unrestrained wall could be deformed sideways quite easily, then become completely rigid with the addition of a thin sheet of ply.

2014-04-20 07.48.53The other thing I was doing was not taking many measurements and fixing dimensions based on the materials I had. In particular I was worried about how wide all the panels would be when joined together. The edge of each panel has an overlap of steel, and a little rebate for the next panel to fit into. I wasn’t confident these would all come together neatly, so the 6 joins might add 60-100mm, in either direction. Similarly, I wanted the downhill end of the roof sheets to overhang the long wall completely so rain definitely wouldn’t come inside. So I installed them all resting on the wall first then made sure the wall was inside that line before I secured it. The result probably isn’t dead straight but I can guarantee it’s strong and waterproof. 2 out of 3 aint bad.

2014-04-23 12.20.09So I pretty much started at the front and worked my way back. The largest oregon beam looked great after planing and oiling, so I made a feature of it along the front, street-facing wall. The long one inside also looked good, so I wanted to make sure it remained exposed inside. To this end I devised a system of attaching the polystyrene panels to the face of the beam.

2014-04-20 11.11.55The panels are 3.1m by about .8m wide, and about 150mm thick. A thick board of polystyrene is bonded to a flat sheet of steel on the bottom and corrugated roof steel on the top. It’s a brilliant material, light, stiff and cheap to make. I wondered how strong they were going to be before installing them and so set one up on a couple of bricks to see how much force they could take. I jumped up and down in the middle, the absolute worst thing to do to them, and they didn’t even flex enough to touch the ground.

I was worried though about how to attach them to things. Polystyrene is fine with a massive surface glued to it, but it’s not really going to hold a screw. So I wanted to cut out about the last 4cm from each end, then screw a piece of wood in its place, with a lot of roofing screws top and bottom. This then gave me something sturdy to attach to the face of the beam.

Getting the polystyrene out was a circus. I didn’t want to lift the steel to get a knife in there, so made a hot knife from a steel strap, bent it into a shape and then heated it up over a camping burner. Once it was glowing hot I could just scoop out the poly. This wasn’t a very fun job, but it worked well.

Even better was the other end, where I wanted to cut the steel on just one side. To do this I got Dave to stand by with the hose while I cut it with an angle grinder. If it caught on fire the plan was Dave would hose everything and we would be fine.

There was also much circus getting the main beam up. I did a lot of the work at home by myself and so had some fairly inventive methods for erecting the component parts. For this one I put together a complicated series of clamps and boards that would hold it vertical while I lifted each end in to place. I got it up easily, but had a brain fade while fixing it in place and took off the wrong clamp. It pivoted on the middle post, yawning ominously as the front end went up and the back went down. I realise what was going on pretty quickly, downed tools and ran outside. As the end went up the forces on the central post got weird and it pushed it over. Broke a hole in the concrete and smashed the beam in the process. Also got my heart racing.

2014-04-21 16.38.24The construction phase was all pretty methodical and in some cases a bit boring. Lots of screwing sheets onto wood. The magnesium oxide panels outside were hard work to install, being in the order of 20kg each. They are also probably the ugliest material I have ever worked with.

2014-05-01 15.52.27Construction phase took about a month, maybe less, and took me to watertight, but not quite locked stage. I didn’t make the front door until quite late in the piece. I was starting to get excited now as the end was in sight. Just some paneling and electricals inside and I was finished!

2014-05-01 15.52.47 2014-05-01 15.51.56 I included this one to show how I interfaced with the brick wall; not at all. Someone on twitter and some reading convinced me I didn’t want to load the house wall, so designed it to be completely freestanding. Then if the slab moves or the shed falls over it won’t damage the house. 2014-05-01 15.52.38





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Shed Project: Design for recycled materials

In general, a design and build project runs like this: define problem, determine solution, design solution, order materials to match the design, build.

But using recycled materials turns this relationship around.

Problem definition remains, but becomes more a set of desires, rather than a strict prescription. I had a 7m x 4m slab, I wanted doors at the front and back and I wanted to keep the rain out. I was hoping for as much uninterrupted space as possible for making things, so was keen to avoid posts in the middle space. That was about it. Anything beyond that is window dressing.

2014-04-12 11.26.14With that in mind I started looking for materials. I already had some massive oregon members lying around from a pergola we pulled down at the new house, but I wasn’t really sure what to do with them. I had in mind running one along both long walls and then putting a flat roof in between them, so was on the lookout for structural timber or steel that could span 4m.

2014-04-14 16.02.24I put the Gumtree app on my phone homepage and checked Home and Garden > Building materials every 15 minutes. Here I got onto the real centrepiece of the build; 130 linear metres of Baltic Pine lining boards, 230mm wide. You just can’t buy these any more. These were salvaged from a 100-year old cottage in Tasmania, some time during the 80s. Shane, then living in Tassie acquired them for a build he was planning, along with some other incredible finds, but was relocated to Canberra with work. Rather than abandon the lot and start again in Canberra he shipped container loads of materials up here and built a house in Canberra. I had a look through it and was absolutely stunned. A sort of reproduction Federation house over 3 split levels, set into a steep hill, overlooking rolling Canberra hills, kangaroos and in pouring rain a waterfall. The house is built from sandstone, with deep verandahs all the way around, salvaged doors and fittings throughout and architectural gems like a wrought iron spiral staircase, wharf timbers for structural members inside and of course a bathroom lined with these boards, hand stripped and sanded by Shane. It is the most beautiful house I have ever seen, with interesting, immaculate components in every room.

2014-03-08 14.46.27I naturally bought every board he had for what felt like an excessive $500, but in hindsight was a total bargain. I told Shane what I was up to and, champion that he is, he got behind the idea and gave me loads of other things he had lying around. It might be the only shed in Australia with cedar molded cornices and skirting boards.

2014-03-16 15.17.20

But this didn’t solve my structural problems and actually put a bit of pressure on the budget. I hadn’t budgeted for $500 worth of internal lining, but obviously I had to have them, so I was looking for savings elsewhere.

I wasn’t having a lot of luck finding structural timbers, and the quotes I received for new wood were terrifying. $600 just to span the distances I had, not including even roofing steel. I needed a breakthrough.

I spent a lot of time poking around Fyshwick builders trading post, a terrific business that specialises in recycled, salvaged and over-ordered building supplies. They had some fantastic polystyrene panels, bonded either side with sheet steel, called sandwich panels. They had wall and roof panels from an old cool-room, but I couldn’t figure out how to use them. The wall panels were the standard 1200mm x 2400 for about $11 and roof panels just over 3m long, 800mm wide and able to support their own weight over that span. I was entranced by their possibility but couldn’t figure out how to use a 3m span. It was a whole metre shorter than my shed was wide.

So I didn’t buy anything and mulled it over while I was driving home. Sometime during the night I came up with a design that could use all these panels and I decided I would swing by in the morning to place a deposit. The plan was to use the longest oregon beam a metre away from the edge of the house, with a single pole in the middle, and the roof panels attached to the beam. I would build a post and beam wall for the long one wall, then just slot the fridge panels in under the beam. Use the strength of the oregon and the insulation and cheap area covering of the fridge panels.

I went to sleep very happy with this plan and patting myself on the back with how clever I was.

Next morning I bundled the boy into the car and toddled over to place my order. I arrived at 10, half an hour after opening. Ten minutes before I arrived someone had called and bought all 60 of the refrigeration panels, but left enough roof panels for me. I was flabbergasted, hurriedly put a deposit on the roof and developed a plan B for the long wall. I found it at the shop, some magnesium oxide panels left over from a big construction job. I’ve never seen anything like them, but apparently they’re common in coastal homes. Magnesium oxide compressed into a board and given strength with fibreglass matting. Very similar to a Gyprock board, but very weather proof.

2014-04-15 15.25.47After that the rest came together pretty easily. I found a huge stash of roof steel literally on the side of the road, enough to do the front and back walls easily, and in a fairly aesthetically coherent manner. I found a sliding glass door on Gumtree for free, and splashed out on an eccentric Federation 15-light glass door for the entry. The dance studio up the road had a big skip out the front so I picked up a few big sheets of yellow-tongue floor boards, perfect for providing structural rigidity. And that was me done. I just had to screw it all together now.

2014-04-01 11.24.19So rather than designing a shed and buying the materials to match my design, I had to find the materials and work backwards from there. Start with the biggest elements first, and the roof span was always going to be the crux. Once they were determined I just filled in the gaps.

At the end of the design phase I had an idea in my head, a couple of sketches in a little book describing how some of the planes come together and materials scattered all over the front yard. It looked a bit like a tip to be honest, but the potential was exciting. I was going to photograph the drawings and include them here, but I’ve lost the notebook and I largely ignored them anyway.

Next: building!



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Shed Project – The Slab

Incredibly, my Pozible reached its target after a little over a week. The timing couldn’t have been better either; I was made redundant on the day I launched the project, so suddenly I had all this free time to make a shed. I pretty much started straight away.

I’m making more of a workshop than shed; it will be a place for making, not storing things, and I will design each part to enhance my making things capabilities. With this in mind, one of the first things I wanted was a nice, smooth, flat floor. During set up I’ll have some heavy machinery to move around and later when I’m making things it’s nice to have a flat floor to use as a reference surface.

The original pegged layout. I actually moved it out after this

The original pegged layout. I actually moved it out after this

The site slopes down to the front left corner, about 300mm fall over about 8 metres. Inconvenient, but manageable. Guidelines suggest 100mm depth of concrete for sheds, 150mm if you want to drive a car onto it. I started at the highest point, the back right corner next to the house, picked a reference point, then laid out formwork in the same plane as this reference. I had some massive oregon beams lying around so I’ve used those, with the plan of repurposing them into the build once the concrete is set. Once the formwork was established as a reference plane I then set about excavating and backfilling until the fill was 100mm below the formwork.

The final layout. The shirt on a stick was to stop me from backing the trailer into it

The final layout. The shirt on a stick was to stop me from backing the trailer into it

This has taken ages! Moving bricks and shoveling gravel is hard work. I lifted pavers and excavated a bit at the top and built up and filled in the bottom. The goal was 100mm coverage for most of the middle of the slab, with a 300-400mm trench around the outside, particularly under the long wall which would be load bearing. So I moved bricks, shoveled gravel and took a lot of measurements. This took about 2 weeks.

Shoveling timeI imported a cubic metre of crushed granite to shape the underslab, then added another half cube of road base on top to harden it. A concreter came over and gave me some good advice “either compact it or leave it for a few weeks”. Leaving it for a few weeks appealed to my lazy side, but a friend had a compactor lying around so I put that to use. The heavy rain didn’t help but after a week of compacting and leveling I was happy.

CompactedOnce I created the form for the underside of the slab I lined it with plastic. This is a ‘vapor barrier’ which controls moisture leaving the slab from below while it’s curing, and makes it stronger as a result. I also use this where the slab meets the wall of the house so there is a break point; if the far edge of the slab erodes or gets really wet, and the slab wants to slide downhill, it won’t take the wall of the house with it.

At this stage we essentially have a 7m x 4m bathtub in the front yard.

This is a biggish slab on a sloping site, so I wanted to make sure it was super strong. I had some welded steel mesh lying around so that went in, reinforcing the channel around the edge and about 40mm below the surface through the middle.

I also have all sorts of different chicken wire and fencing mesh, some dodgy bits and a couple of rolls. I wanted to use that but didn’t know much about how it would work, so did some reading.

Steel in concrete is a classic composite material. Concrete is very strong under compressive loads, terrible under tensile loads. Steel is pretty good under compression, but expensive to achieve that strength, and incredibly strong under tension. How does a slab experience a tensile load? Imagine an exaggerated case where the substrate for the whole front third of the slab washes away in the rain. The bit that is now suspended in the air will want to sag. This creates a tensile load in the top of the slab where it is trying to stretch, and compressive load under the slab where it is being squashed.

Not only is concrete bad at tension, it experiences brittle failure. Brittle failure is the difference between chocolate at room temperature and refrigerated chocolate. At room temperature, and higher, chocolate bends then slowly fails. When refrigerated it snaps. Brittle failure means cracks form and propagate quickly. Glass, ice, ceramics, anything that shatters undergoes brittle failure.

Steel prevents cracks propagating in concrete. If a situation arises that puts the concrete under tension steel acts to limit the stretch and so stops cracks forming.

This theory is applied to composites everywhere; one material that’s good with compression combined with another good at tension. Fibreglass is a common example. Incredibly, fibres made of glass can handle quite a lot of tension. The resin they are suspended in is better at compression. Carbon fibre is another, usually combined with a similar resin to that used in fibreglass. Chewing gum and hair also form a powerful composite material.

Steel in the slab

Knowing all of this I decided I couldn’t put too much steel into the concrete. so I’ve rolled out the mesh and folded it into complicated shapes to link the channel around the edge with the centre. This combination of concrete and steel is known as ferroconcrete, and is one of the strongest materials known to man. It’s so good that if Noah were making a new ark I would recommend he use ferroconcrete. Strong, easy to work with and made from simple components.

Pouring Day

We poured on a Saturday, after a week of rain. Half a dozen friends came over to help and it went fairly well.

Slab teamTeam slab: Gavin, Ben, Donna, Evan, Dayne, Sean, Glen

The truck backed up to the slab but couldn’t pour to the far corner, so we barrowed the first half or so. Then once we could pour directly it all happened rather quickly. We stomped and smooshed the concrete into the corners and leveled it as best we could by eye. I ordered heaps too much so we also poured a dodgy extension to the driveway at the same time.

2014-04-12 08.03.16Keen to avoid spending $400 on a special concreting screed I bought some steel channel from the tip shop for $4 and made my own. Dayne said it was ‘okay’. I think the biggest mistake I made was not making the reference against the wall thick enough. I screwed a piece of angle steel on to use as a ledge while screeding, but the lip wasn’t thick enough and it was hard to use. I have no idea how to fix this without burying a piece of wood in the slab forever, but it’s probably not a problem I’ll ever have to deal with again.

2014-04-12 09.23.32Pouring and screeding took about 3 hours. The formwork (apart from against the wall) worked really well and the slab was obviously flat. At this stage the concrete is rough, with sand and aggregate poking up in places. To fix that one uses a bull float, back and forth for half an hour, maybe longer. This pushes the lumps down and brings up the mix of water and cement. This just makes the finish nicer.

2014-04-12 11.26.14The Zen of Bull Floating

After that we waited for the perfect moment to begin hand finishing. I waited, tested and waited. Then I got distracted doing something else and came back to find it much harder than I wanted. I did some hand polishing but it was utterly exhausting and hardly made a difference. At about this time I decided it was ‘good enough’ and called it finished.

2014-04-12 12.20.14I considered hiring a polisher and making the slab beautiful, but decided against it. This was partly targeted laziness and partly robust ethical consideration. Part of why I like recycled materials is the character they bring. Accept that reused materials will be imperfect and just enjoy their lack of uniformity. I think we get carried away seeking perfection and invest far more energy than we need to in making things. So why not just accept it when it works and admire its differences?

2014-04-12 15.57.44I popped the formwork off after a few days and pulled out the star pickets. The rain really helped with that. I’ve now started laying out the construction materials, so Slab Phase is officially over.

2014-04-14 16.02.24


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Learning to cut dovetail joints

I made a couple of New Year Resolutions this year, which is unusual for me. Although, I think the last two I probably went for were ‘parent better’ and ‘drink less’.

But this year I have two SMART (specific, measurable, achievable, realistic timely) goals; raise a pig for the table and learn how to hand cut dovetail joints.

The pigs will probably live through this year, as we’re planning on housing some on Cansdell farm later in September or so, but I am putting a cross through “learn to cut dovetails”. This post will talk about my learning process.

The dovetail joint has seemed like witch-craft to me for years. My Dad was a great woodworker, but even more so he instilled a wonder in other people’s work. We would look at furniture and he would point out bits that were hard or clever. Dovetails always seemed like some sort of threshold to me, the point you cross between handy-person and woodworker. And they are the first thing to disappear when furniture gets cut by machine. I like IKEA, but it will be a long time before they release hand-cut, dovetailed kitchen drawers.

2014-01-08 10.20.39

I had dabbled with the idea for a while, even going as far as buying a back-saw (tenon saw) and a sharpening stone for my chisels. But the thing that pushed me over from thinker to doer was a bundle of woodworking magazines that arrived in the post, the end of Dad’s subscription after he died 18 months or so ago. In a flurry of nostalgia and casting about for a project I decided to learn these things once and for all.

I think this was part of the eventual success; I wasn’t trying to make something, I wanted to learn a new skill. Learn it so I could do it in my sleep, and then dovetail every piece of wood in the house. This meant there was no time pressure, no need for them to be good from the outset, I could focus on the process, the continuous marginal improvement which comes from learning a new skill.

The tools I used throughout were pretty simple; a cheap tenon saw, a cheap chisel, a good wooden mallet, a razor blade and my bench and vice.

I started by watching some videos. This was the best one to get me moving:

Seeing someone do them so quickly made it much more accessible. About 3 minutes and he has a corner done! Very neatly too I might add. Armed with this basic technique I went and cut some joints.

The first 4 were pretty bad, but there were little improvements each time. Better chisel technique, straighter sawing, more accurate marking. Here are the first 5; number two exploded during assembly.

2014-02-02 19.36.00During this period I read a bit of dovetail theory and history, which helped with my confidence and ability to just give it a go. Dovetails were developed as a fast and dirty way to join two boards. You cut the tails by hand. It virtually doesn’t matter what they look like, as long as they are perpendicular to the plane of the face. Then mark the pins off those tails, and cut them exactly. So the crux is that marking, then cutting operation, and most of the improvements in the second half of the test series were found here.

This video helped a lot as well …particularly because of the jig he uses. I lusted after one for a while, before realising I could make one myself pretty easily. I’ll write a post on that separately, but here is the jig and the first joint I cut using it. A marked improvement.

2014-01-12 14.50.20

The jig sorted out my sawing technique, making much straighter, sharper lines. Another marginal improvement came from clamping the jig rather than holding it.

The last piece in the puzzle was my chisel technique. For me, the most difficult part is neatly removing the waste from between the tails/pins. I was using 19mm board for most of my practice, which meant I needed to do more chiseling than in the videos, which were typically using 10mm and quite soft boards. So I watched some videos on sharpening chisels first, then some different techniques. I settled on ‘pairing’ in the end, where a vertical cut is made with the chisel on the line, then the fibres are dug out sideways until you get to the bottom of the initial cut. Then repeat.

2014-02-02 19.36.10By number 9 I was ready to make something. I bought a piece of FSC Tassie Oak from Bunnings and set to work. A week later and I have my first box.

2014-02-02 17.27.32

It looks much nicer than I expected, and sturdy enough to hold anything that will fit in it. Perhaps not a dynamic toddler. I am happy with the product, but more than anything I am happy that I know dovetails now. Even during the box I ironed out a few little technical problems and picked up a few pointers for next time.

2014-01-30 08.26.40I am not using a pencil for marking ever again. Before gluing up there was an obvious difference between the first and second pair of joins, traced back to pencil marking. The pins and tails need to match really closely, each side very close to, but not crossing an imaginary line. So you mark the line as sharply as possible, then cut up to, but not over the line. Under cutting is better as you can shave off a little during assembly.

2014-01-28 20.12.20Now that I know I just want to spend all of my time cutting them. What else could I dovetail? Where can I get more wood? I’m really interested in ways of upcycling wooden pallets at the moment, particularly the soft-wood ones which are commonly discarded. At least there are plenty around to practice on. I’ll let you know how I go.


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A question for AGW “skeptics”

For better or worse, I have spent quite a bit of time arguing with “humans are causing global warming and it’s a bad thing” deniers/skeptics on the internet. I don’t expect I will ever change their minds, in fact I am increasingly sure that I can’t change their minds, but it’s interesting to have a discussion and see where their objections lie. Then I know more for the next one I meet, and I might be able to convince a couple more observers, who I think are the main candidates for having their minds changed.

For the record, I accept that human emissions of CO2 are changing the climate and that this is a bad thing. I don’t ‘believe’ this. You don’t need to believe in things that can be measured.

Something interesting has emerged from these discussions: I think I have found the denier’s kyptonite.

In all of these discussions, and I don’t think I’m exaggerating to suggest there have been more than a hundred, none of them have even offered a sliver of an answer to the following question:

If the globe was warming due to human actions, what would evidence of it look like?

No one has ever attempted to answer this question. Some have said “well I can tell you what it doesn’t look like” and “the world hasn’t warmed in 15 years” but never has there been an honest attempt to describe something which constitutes evidence that humans are causing the climate to change.

It is incredible that people so well versed in science that they can disregard the vast bulk of scientific work on a topic can’t answer this question. They can describe in great detail why any given piece of evidence isn’t evidence of climate change, but not what would be. This is the very essence of both science and skepticism; once you know a theory you know what will break it and you look for it, constantly.

I am not overly surprised, the skeptics I have debated don’t usually answer any questions at all. I suspect this is because on some level they know that once they offer a position on something they can be disproven, and that’s dangerous territory. Much better to make wild accusations and ask questions, and then you can never be wrong.

I’m not sure what to do with this information; it’s not going to change the politics or the difficulty of achieving global agreement on emissions limits. But I think it indicates a strategy. What if rather than people like Andrew Bolt getting away with nonsense such as “the world hasn’t warmed in 15 years” someone replied with “great point Andrew. You seem to know an awful lot about global warming, what do you think evidence supporting the theory would look like if it were occurring?”

Let’s start asking, not answering, questions from the skeptics among us. They know SO MUCH, and we should try and learn from them.

Assuming of course they have anything to offer.


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TED Talk – A low energy use life is glorious.

I did a TEDx Talk in Canberra recently. Here’s the video:

In this talk I wanted to get people excited about an energy efficient lifestyle. Rather than the Earth Hour view that to save the planet we need to go without I think an energy efficient lifestyle is actually pretty nice and this talk focuses on some of the co-benefits that come with energy efficiency, using some examples from my industrial career.

Let me know what you think.


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