Summary

We have measured the net internal (NIA) area of all residential properties and broken down the average size of housing stock in each postcode according to their number of bedrooms and built form.

Defintion

The net internal area (NIA) of a property is defined as the usable area measured to the internal finish of the perimeter or party walls in square meters (sq.m). This matches the definition used by the RICS Residential Agency Guidelines.

Why the metric matters from a commercial inhabitant’s perspective?

Average property size matters significantly from a commercial inhabitant’s perspective as it directly impacts operational efficiency, cost management, and scalability. A property that aligns with the business’s space requirements can optimize workflows, ensuring sufficient room for equipment, inventory, and customer interactions without unnecessary expenditure on underutilized areas. For industries such as retail or manufacturing, a well-sized property supports effective layout planning, enhancing customer experiences or production processes. Additionally, larger properties may provide opportunities for future expansion, while smaller spaces can reduce overhead for startups or businesses prioritizing cost-effectiveness. Striking the right balance ensures that the property size complements the business’s operational and strategic goals.

Why the metric matters from a residential inhabitant’s perspective?

Average property size is crucial from a residential inhabitant’s perspective as it influences comfort, functionality, and long-term suitability. A well-sized property ensures enough space to accommodate the household’s needs, such as living areas, bedrooms, storage, and recreational zones, promoting a comfortable and organized lifestyle. For families, larger properties may provide room for growth, privacy, and outdoor activities, while smaller spaces can offer affordability and easier maintenance for singles or couples. The property’s size also impacts social dynamics, as sufficient room can enhance relationships by reducing overcrowding. Ultimately, the right property size contributes to a sense of belonging and quality of life.

General Commentary

Although real estate is a tangible asset, it can also be viewed as a “bundle” of intangible rights. These rights are to the services, or benefits, that real estate provides its users. For example, property provides owners with the rights to shelter, security, and privacy, as well as a location that facilitates business or residential activities. This concept of property as a bundle of rights is extremely important to understanding real estate. As you may know, the value of a bundle of rights is a function of the property’s property-specific characteristics, location-specific characteristics, and legal characteristics. The most important of the property-specific-characteristics is generally size. Size really matters. Other property specific-characteristics include the age, design, and construction quality of the property, as well as its shape other natural features of the land on which the property is situated. For residential property, location-specific-characteristics include convenience and access to places of employment, schools, shopping, health care facilities, and other places important to households.

Trivia

The highest average property size of all the London boroughs are generally found in Kensington & Chelsea. The lowest is unsurprisingly in the City of London.

History

British house sizes have generally improved over the last two centuries. From the 18th to 19th century, during the British industrial revolution, poor British citizens (especially those living in urban areas) often lived in small poor quality housing stock. By the end of the first world war almost 80% of British people rented homes, with almost all of them from private landlords who could easily profit from renting overcrowded accommodation. Consequentially, Prime Minister, David Lloyd-George, set out to improve housing quality and stock by funding local authorities through the 1919 Housing Act to build council homes which were generally much better and more spacious than prior alternatives. Since the 1930s house specification data started to be extensively recorded, and consensus analysis shows that in the 1930s houses had an average master bedroom size of 15.34 metres squared. By the 1940s this decreased by 1.52 due to a need for more bedrooms in the wake of The Blitz during World War Two. The 1960s saw the 1963 Parker Morris Standards which enforced minimum room sizes that are still used today, but also an increase in tower block housing, with over 55,000 built between 1960 and 1965. House sizes generally improved in the later part in this decade, and from the 1970s to the 1990s the average master bedroom size was around 14.5m2, and in the 2000s this continued to decrease from the 1930s housing size highs. Surprisingly, the size of British houses has decreased from the 1930s, whilst living conditions have markedly improved.