Permitted Development (PD) is the set of laws that determine what can be built in the UK without needing planning permission. These laws, which have existed since 1947, typically cover smallscale developments that have a minor impact on their surroundings. In 2008 the laws covering household developments were radically revised in an effort to free up planning departments to focus on larger applications. But the rewritten laws, while inherently more ‘liberal’ than their predecessors, are also confusing, impractical, and obscured by legalese.

Since 2009, we have produced a series of projects with a number of collaborators that explore PD. These projects all involve engaging with the laws in order to make public their potential for development. We see this work as a form of spatial practice.

This article presents an edited selection of spreads from our 2009 book-pamphlet SUB-PLAN: A Guide to Permitted Development, which was produced with the graphic design studio Europa and a group of students at the Architectural Association Summer School.