The Act That Nationalised Development Rights
The Town and Country Planning Act 1947 is the foundation of modern UK property law. It effectively nationalised the right to develop land, meaning you no longer owned the right to build on your own property.
Before 1947, if you owned a piece of land in the UK, you largely owned the right to build whatever you wanted on it, subject to local bylaws. The Town and Country Planning Act 1947 changed everything. It is arguably the most powerful and restrictive piece of property legislation ever passed in the UK.
The Nationalisation of Development
The Act fundamentally separated the 'ownership' of land from the 'right to develop' that land. It nationalised development rights, meaning that while you still owned the soil, the State owned the right to decide what could be built on it. From 1947 onwards, anyone wishing to build or change the use of a property had to seek 'Planning Permission' from the local authority.
This single piece of legislation is responsible for the enormous disparity between agricultural land values (£10,000 per acre) and residential development land values (£1M+ per acre). The entire UK property development industry is based on the arbitrage of navigating this Act to secure permission and unlock the land's artificial value.