Designers of complex communities always make use of sub-contractors. No big prime contractor wants to spend money on doing things themselves that they can buy more efficiently from a supplier or a subcontractor. (e.g., the people who build the school are unlikely to have a factory producing the electrical cabling for it nor a glass factory producing the sheet glass for the windows).

For your environmentally sustainable earth settlement design challenge, we have designed a short list of fictional subcontractors, based on average prices of what’s available currently in the UK. These are just a guideline, to speed up your research in a time-limited challenge. If you can think of something that exists, or might exist, in real life (and you can find it online) then you can use it.

Remember that wherever your RfEP is located, some things will be easier to source than others. For instance, if you want sand in the sandy Sahara Desert, it seems that it’s going to be pretty cheaply available but do ask yourselves questions about how will you collect it and move it to where you want it? Will it stay in place? Is enclosed storage required? What transport, packaging and labour would be needed, in addition to ‘the sand’? If you want bulk sand inside the Arctic circle, you must take into account the cost of sourcing and moving your materials to your building site, as well as the carbon footprint you will be leaving by shipping materials around the world. Sub-contractors and suppliers can be efficient, but you do have to think about the process involved in using them. Is there a better alternative closer to home? What transport and logistics are involved in using the sub-contractor? In north western Australia, mining ores require transport using enormous trucks and loading onto the longest ‘freight trains’ in the world. These logistics are issues that affect your choice of sub-contractor services.