MYP Design Sustainable Design Strategies Notes

The Six Rs Are a Checklist, Ordered by How Much Each One Saves

1. The six Rs are rethink, refuse, reduce, reuse, repair and recycle, and they work as a list of questions you run over a design before you commit to making it.
2. The order is deliberate, running from the biggest saving to the smallest, so rethinking a product out of existence beats recycling it after twenty uses.
3. Recycling sits last because it still burns energy, still loses material quality on every pass, and still needs collecting, sorting and transporting first.
4. Most school projects leap straight to recycle, which is the weakest of the six and the easiest to claim without any evidence behind it.
5. Use the list as questions rather than labels, asking what it would take to not make this at all, and what it would take to halve its mass.
6. In MYP terms this is the related concept sustainability, and projects built on it usually sit in the global context of globalization and sustainability.

Rethink and Refuse Come First Because They Delete the Problem

1. Rethink asks whether the need could be met a completely different way, which is where the largest savings are hiding.
2. A shared tool library, a charging point built into lockers the school already owns, or a service instead of an object all satisfy a need without a new product existing.
3. Rethinking can change the business model too, as with a printer sold cheaply that locks you into sealed cartridges versus one designed around refillable ink tanks.
4. Refuse means turning down a material, a process or a feature that costs more than it gives back.
5. That looks like saying no to the shrink wrap, the second card box, the chrome trim strip or the indicator LED that glows all night doing nothing.
6. Record both as evidence, naming the option you refused and why, because a rejected idea with a stated reason earns more credit than an option nobody considered.

Reduce: Less Material Doing the Same Job

1. Reduce means using less material, less energy or fewer separate parts to reach the same performance.
2. Material efficiency starts with nesting, arranging parts on a sheet so the offcut is tiny, which laser cutter software will do for you if you group the parts before sending the file.
3. Thinner does not always mean weaker, since a 2 mm sheet folded into an L section resists bending far better than a flat 4 mm sheet of the same width.
4. Ribs and folds buy stiffness for almost no extra mass, which is why the underside of a moulded plastic chair seat looks like a honeycomb.
5. Fewer parts means fewer joints, less assembly time and less sorting at the end, so one cleverly shaped moulding often beats a five piece bolted assembly.
6. Measure the saving instead of asserting it: weigh the old version and the new one and put both numbers into your evaluation.

Reuse and Repair Keep the Object Alive

1. Reuse means the object or its parts get used again as they are, without being shredded, melted or reprocessed.
2. Design for reuse by making the thing durable, plain enough that it will not look dated in five years, and useful to a second owner, which is why glass jars outlive their first contents.
3. Repair keeps a product in service by replacing the one component that failed rather than the whole assembly.
4. Design for repair means standard fasteners, a published exploded drawing, spare parts you can actually buy, and nothing critical hidden behind a glued panel.
5. The wear parts should be the easiest to reach, because the battery, the filter, the seal or the blade will fail first and a good design expects it.
6. Test this on your own work by timing how long it takes to open your prototype with a screwdriver and noting exactly what got in the way.

Design for Disassembly Decides Whether Recycling Is Even Possible

1. Design for disassembly means designing the product so it comes apart into clean separate materials using tools an ordinary person owns.
2. Glue, ultrasonic welding and overmoulding bond two materials permanently, so the recycler can only shred them together and accept a contaminated mixture worth very little.
3. Screws, bolts, clips and snap fits come apart again, so the steel goes into the steel stream and the polypropylene goes into the polypropylene stream.
4. Using fewer different materials helps even more, since a product made of one polymer plus steel screws sorts in seconds while one made of six polymers does not sort at all.
5. Moulding the polymer code into the inside surface of each part tells whoever dismantles it exactly what they are holding.
6. Keep the number and type of fasteners low, because a product needing four different screwdriver bits gets thrown away rather than opened.

Energy in Use Often Matters More Than the Material You Picked

1. For anything that plugs in, burns fuel or heats water, the energy it uses while working usually dwarfs the energy that went into making it.
2. A fridge left running for fifteen years spends far more energy in use than in manufacture, so insulation thickness and compressor efficiency matter more than which plastic the door handle is.
3. For a chair, a bag or a shelf the balance flips completely, because nothing is consumed in use and the material choice decides nearly all of the impact.
4. Work out which kind of product yours is before deciding where to spend your design effort.
5. Renewable materials regrow on a human timescale, including timber from certified forests, bamboo, cork and wool, though renewable does not automatically mean low impact if it travels 8000 km to reach you.
6. Recycled materials skip the extraction stage entirely, and recycled aluminium needs roughly 5 percent of the energy that smelting fresh aluminium from bauxite demands.
7. The properties and processing of particular materials belong to the materials articles; the question here is only how a choice between them changes the impact.

What You Can Realistically Change in a School Project

1. You will not reorganise a supply chain, but you do control material choice, joining method, part count and packaging, and those are exactly what the criteria ask you to justify.
2. Design around stock the workshop already holds, because building a part from a 3 mm plywood offcut wastes nothing while ordering a fresh sheet for one bracket wastes most of it.
3. Choose mechanical fasteners over glue wherever the loads allow, then say in your evaluation that you chose them for disassembly.
4. Prototype in the cheapest material that behaves similarly, since testing a hinge in 3 mm MDF before cutting acrylic saves the acrylic, the machine time and your deadline.
5. Design the packaging out where you can, and where you cannot, make it from one named material rather than a laminate.
6. Tie each decision to one of the six Rs in writing, because the reasoning is credited as heavily as the finished object.