Design for sustainability

Waste, pollution and energy consumption — and all three are affected more by how long the product lasts than by what it is made of.

Doubling the time a product stays in use halves its material, energy and waste at once, because one product does the work of two. No material substitution comes close.

For anything powered the use phase dominates, so insulation and control matter. For anything passive the embodied impact dominates, so mass, processes and life matter.

A measure, a cost and an alternative — for example, "the recycled grade costs 12% more per part and removes the coating, recovered within a year".

Cyclic (creates no waste), solar (uses clean energy), safe (causes no harm), efficient (least material and energy), social (supports basic human rights).

That every part can return to a cycle — made from recycled or renewable material and recyclable or compostable at the end. A laminate or a glued joint usually breaks it.

Mass and energy only mean something against the service delivered. A chair 40% lighter that lasts half as long uses more material per year of use.

Below tier one of the supply chain: final assembly is visible and audited, while the fabric, fixings and raw materials are two or three tiers away and rarely traced.

Measuring a product against three accounts — people (social), profit (economic) and planet (environmental) — together rather than measuring profit alone.

Users, the community round the factory, everyone in the supply chain, and the people who repair, clean or dispose of the product. The supply chain is the forgotten part.

A design that loses money is never manufactured, so it helps nobody. Profit is a constraint to be met, not a villain, and the version that ships balances all three.

By changing what the product IS rather than optimising what it was: shipping concentrate instead of water, renting a tool instead of selling one.

Find the account that is quietly paying and name what it pays for. A product that seems unusually cheap or convenient is being subsidised by people, profit or planet.

A decision that moves a cost instead of removing it — a thinner bottle onto the user, a refill onto the household, automation from profit onto people. Check all three accounts after any change.

Safety and legality are not tradeable. Then favour the account that cannot recover — a lost livelihood or habitat — over one that can. Then take the whole-life view of profit.

Durability that costs more per unit is usually cheaper per year of service, so what looks like profit against planet at the till is often profit and planet over ten years.