For example, on the first week of January you may pick up envelopes 10 and 33. You'd therefore put £10 in the 10 envelope and 33 in the 33 envelope (or in a sealed moneybox, if you'd prefer).

[The Sapa Building System technical essay, RIBA Awards 2012] More than the plan, more than the section, and even more than form, the envelope is central to how a building communicates, writes Felix ...